Term
| What are the fundamental principles of ecology? |
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Definition
1. The individuals are spread randomly (heterogeneously through space and time
2. Variation in individuals leads to variation in population
3. Organisms are effected by both biotic and abiotic factors
4. Environmental conditions are heterogeneous through space and time
5. Resources are finite and heterogeneously spread through an environment
6. Birth and Death rates are dependent on the biotic and abiotic factors in an environment |
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Term
| What did (Belovsky, 1978) find out about herbivore foraging strategy? |
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Definition
| He found by using adult moose as a studied organism that the moose has an optimum size and that too big and they were poor forages as it was hard to gain enough and too small and they were not able to access the right nutrient easily. |
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Term
| What are the 6 fundamental foraging types? |
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Definition
1. Herbivore
2. Predator.
3. Fungivore
4. Parasite
5. Parasitoid
6. Detritivore |
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Term
| What did (Bai & Smith, 1993) find out about parasitoids? |
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Definition
| That the parasitoid wasp T. minutum was able to control it's number of offspring depending on the host availability. The larger or more nutritious the host, the more offspring the mother will produce. This is an example of host abundance dependent fertility. |
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Term
| What are the 3 fundamental diet types? |
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Definition
1. Monophagous - Specialist, will eat one specific energy source
2. Oligophagous - Fairly specialised but ill eat around the similarly related food types
3. Polyphagous - Generalist, will eat anything
Can be varying degrees of these diet types. |
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Term
| What are the two types of variation in species and what do they mean? |
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Definition
Obligate and Facultative
Obligate is genetic variation within a species, can lead to subspecies. Can be to do with genetic differences of developmental/size differences which leads to different mate choice etc.
Facultative is environmental and behavioural. The variation comes in with the availability of what is around them and then this changes behaviour and diet is dependent on this and such. |
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Term
| What did (Lemon, 1991) find out about optimal foraging? |
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Definition
He studied zebra finch as a model organism and found that there fitness was positively correlated to their net energy gain
The fitness was measured by using population growth rate as an indicator and this was then used to show that the more optimal the foraging, the higher the pop growth rate |
|
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Term
| What is optimal foraging? |
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Definition
It is the ability to maximise the energy gain whilst minimising the energy expenditure and time taken
Shown as Efficiency = Energy gained/Time taken |
|
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Term
| What are the three components of fitness? |
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Definition
Development rate
Fecundity (reproductive rate)
Survival |
|
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Term
| What are the constraints of the optimal foraging model? |
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Definition
What kind of prey and animal needs to take
Whereabouts to forage
When to move to a new foraging patch
How far away foraging patches are
How much sodium is required for survival
Water source
Stomach capacity |
|
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Term
| What are the responses to resource density? |
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Definition
Individual response:
- Rapid response with higher feeding rates
Population response:
- Slow responses
- Survival will fall or rise
- Reproduction will fall or rise
- Recruitment in a population will fall or rise |
|
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Term
| What are the three functional responses to differing foraging conditions? |
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Definition
Changing the:
- Handling time
- Searching time
- Learning (when to switch to a new patch) |
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Term
| What are the three forms of numerical responses to differing foraging conditions? |
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Definition
1. Survival - as competition increases on a patch, survival rates will decrease (this is especially true in scramble competition)
2. Reproduction - fecundity decreases as population density increases
3. Aggregation - Higher predator densities accumulate around areas of high prey density |
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Term
| What is they key to optimal foraging? |
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Definition
| Finding a high quality patch quickly and staying in it until the competition backlash outweighs nutritional gain and the nutrition begins to deplete and then knowing when to move on to another high quality patch |
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Term
| What is the marginal value theorem? (To do with optimal foraging) |
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Definition
[image]
The idea of all the optimal foraging theories put together. The time to find a new patch, the depleting nutritional gain from a patch over time and the knowing when to leave. The MVT is applicable when the food sources are patchy and when the quality of the patch depletes over time |
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Term
| What did (Watnabe, 2014) find out about the marginal value theorem? |
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Definition
| He used Adelie penguins (P. adeliae) and found that they will stay longer in good patches but they will also stay longer in an average patch if it's in a bad environment as they know this is the best they will find in the close area. |
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Term
| What are the four key processes of demography? |
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Definition
| Births, Deaths, Emigration and Immigration |
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Term
| What is the difference between Obligate and Facultative? |
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Definition
Obligate is the idea of hardwired differences and actions. To do with genetics
Facultative is the behavioural differences and actions. |
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Term
| What does lambda represent? |
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Definition
It represents the population growth rate in a static moment in time
It is the population in the next time phase divided by the population in the current time phase |
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Term
| What are the two types of life history and describe them |
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Definition
These are age specific and stage specific.
Most easily described by using mammals as an example for age specific and they will go through the ages in a linear fashion and this will never change and it is easier to predict and measure
Stage-specific is often associated with plants and some cnidarians. They are able to stay in a particular stage independent of their age depending on whether their conditions are correct to move onto the next stage |
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Term
| Why is it so hard to find a value for lambda? |
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Definition
| It's hard to work out the movement between different populations and to set certain boundaries for the different populations. |
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Term
| Why is it so hard to map a life history of a population? |
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Definition
| Because you must know all the numbers of individuals in the population that are in a certain life stage. This makes it hard to find out how a population is doing in terms of overall population fitness. |
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Term
| What are different life history strategies and what exactly do they mean? |
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Definition
Different ways to go about different processes in life.
Different modes of growth- Modular (in plants) and then Unitary (indeterminate (continuing growing until death) and determinate (reaching a final size and then stop growing independent of age))
Also reproduction strategy, can be separate sexes, hermaphrodite, asexual and even alternating of generation's methods based on surrounding habitat quality. |
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Term
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Definition
It is the series of changes an organism goes through in it's life.
Can be applied to population and species and other bigger picture things |
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Term
| What are the different columns in a life history table? |
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Definition
x = the stage
nx = the number of individuals in that stage
lx = age specific survival rate
qx = age specific mortality rate
kx = the killing power, this is the additive effects of all the mortality rates at each life stage until that specific stage
bx = the birth rate |
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Term
| What common survival trends are shown when looking at different animals life history tables? |
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Definition
Type I - Humans and zoo animals
Type II - Large mammals/birds and seed banks
Type III - Other birds, fish, smaller mammals |
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Term
| Why is dispersal often ignored in life tables? (the immigration and emigration part) |
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Definition
- The dispersal is only really done by one sex (usually males)
- Juveniles and young adults are the one dispersing |
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Term
| Why is dispersal important in populations? |
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Definition
Prevents inbreeding
Reduces competition amongst young related juveniles
Creates more heterogeneous habitats through space and time
However the issues are there can be:
- Outbreeding with populations (individuals are too distantly related to created viable offspring (different species)
- Individuals can be locally adapted and when the leave their survival chances may fall |
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Term
| When can you use lambda to explain population growth? |
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Definition
When the generations are non overlapping. This means that when one generation dies, the next generation will begin.
This is rare in ecology but will occur in some insect colonies including field grasshoppers |
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Term
| When is population exponential? |
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Definition
| In states of invasion and recovery. No other time due to density dependent growth rate otherwise known as the LOGISTIC GROWTH RATE. |
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Term
| Difference between deterministic and stochastic? |
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Definition
Deterministic is just what is predicted with no outside factors or anything, it's just the inevitable if nothing changes
Stochastic is the interference from biotic and abiotic factors, the random noise that interferes with life |
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Term
| What are the various kinds of stochasticity? |
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Definition
There is environmental
- Weather
- Resource fluctuations
Demographic
- Who will die
- B or G?
- Offspring number |
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Term
| What did (Melbourne and Hastings, 2008) use as the 4 factors of population interference? |
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Definition
| Demographic heterogeneity - Differing levels of fecundity between individuals in a population Demographic stochasticity - The probability of death or reproduction in an individual Environmental stochasticity - The variation of birth and death rates in a population throughout location and times. Effected by weather and resource fluctuations. Sex deterministic stochasticity - Whether an individual is a boy or a girl |
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Term
| What are the two main types of competition and how do they compare? |
|
Definition
Scramble and Contest
Scramble will usually result in a fair share between all members so as long as there is enough resources, everyone will survive but if there is just short of enough resources, no one will get quite enough and theoretically, all individuals will die
Contest is when there tends to be a hierarchy and this means that there is an unequal share of the resources with more dominant individuals getting more of the share. If resources fall then the subordinates will be the first to die, theoretically. |
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Term
| What did (McKellar et al, 2013) find out about density dependence? |
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Definition
| He used Redstarts to show that the higher the density of females in an area, the lower the number of offspring the mother would have. This is an example of population density dependent reproduction rate. The mother knows that they may be subject to lower quality or less resources and therefore are able to invest less into offspring so have less. |
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Term
| What is the actually reason for slowing of the reproduction rate at higher densities? |
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Definition
|
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Term
| What did (Melbourne & Hastings, 2008) find out about Stochasticity? |
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Definition
They used T. casteneum to create a more varied stochasticity model to the one in practice usually.
They used the four types of stochasticity we use today:
1) Demographic stochasticity (probability individual will die or reproduce at a given point)
2) Environmental stochasticity (the variation in demographic in different time and space)
3) Sex determination stochasticity (Whether offspring is B or G
4) Demographic Heterogeneity (Differing levels of fecundity between individuals in a population) |
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Term
| What did (Bascompte & Sole, 1996) find out about habitat degradation? |
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Definition
They used a pice of black paper and then began to punch random holes in it to show that degradation of habitat quality was not a linear process and that the it was a slow starting exponential process that was hard to recover from
Also showed that as populations began to decrease in size, they began to become more and more at risk to stochasticity. |
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Term
| What did (McKellar et al., 2013) find out about density dependence? |
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Definition
| Using Sylvia atricapilla, Eurasian Blackcap, they found that as the population density increased, the number offspring a mother had decreased in value, this was due to the idea that the mother would have the maximum number of offspring that she thought she would be able to handle in the current habitat conditions |
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Term
| What did (Benoit, et al., 1998) discover about the population fluctuation? |
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Definition
He found that when looking at flour beetles, population fluctuations were much more prevalent when there was pupal cannibalism present.
Not sure where this applies |
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Term
| What did (Fujiwara & Caswell, 2001) find out about population growth? |
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Definition
They used the Northern Right Whale populations to map population growth which was in decline at the time and found that by just saving two every year it would become positive. This was because the rate of logistic population growth was below 0 but only just.
It was also because the whale has a very large T value which means that one life becomes more valuable in terms of rN |
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Term
| What did (Simmons, 2009) find out about genetics? |
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Definition
He found average lambda values for various species and found that genetic bet hedging was the best way to survive as it was most resilient to stochasticity
This is because stochasticity can be quite specific and this means that the populations with specific means of surviving become vulnerable if they are effected by stochasticity |
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Term
| What did (Hanksi, 1998) find out about stochasticity and who does it challenge? |
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Definition
It challenges the (Melbourne & Hastings, 2008) paper because it discusses 4 different types of stochasticity
It uses:
- Demographic stochasticity
- Immigration and extinction probability
- Regional stochasticity
- Environmental stochasticity |
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Term
| What did (Soulé, 1986) find out about species extinction boundaries? |
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Definition
| He said that the magic number for a species with an average T value was 20 breeding female individuals to keep a population from becoming extinct |
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Term
| What did (Lima & Berryman, 2011) find out about human populations? |
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Definition
They looked at the density dependence relevance in human populations and found that H. sapiens are reacting in a similar way to other species when reaching an upper limit of a K value and the r values are declining in all areas apart from African countries. This shows that the R0 value is decreasing.
Showed 45 years of negative feedback for increasing population in the R0 value |
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Term
| How does density dependence effect competition? |
|
Definition
Scramble competition leads to a decline in reproduction and population once the population rises above a K value
Contest competition leads to a asymptote of the population when the population is high as the highest percent will survive and the others will not be able to access the nutrients the require to survive |
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Term
| How does density dependence effect development and fecundity? |
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Definition
| In areas of high pop density, the fecundity tends to reduce in value and so does the development time, this is usually due to more competition for resources however and the less nutrients each individual can obtain |
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Term
|
Definition
Maximum sustainable yield
This can be a value anywhere that falls within the curve of Density to population recruitment. This means that as long as the population is at at high enough level and the recruitment is high enough then you are able to harvest from that population |
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Term
| What are the two major types of abiotic fluctuations that will cause population changes? |
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Definition
Climatic forcing - Makes large scale long term changes (e.g. El nino)
Stochasticity - Demographic and Environmental randomness |
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Term
| How do types of competition explain differen types of population dynamics? |
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Definition
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|
Term
| What is an example of human influenced population dynamics? |
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Definition
(Kausrud et al., 2008) looked at Lemmings and there population relationship within the last in the last 40 years.
Found that the climate change was ruining the amount of snow that was falling and the irregularity of it all and then then their habitat under the crust of the snow does not exist and then they have altered overwinter survival |
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Term
| How can sustainable fishing actually encourage increased rate of reproduction? |
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Definition
By removing older fish from the sea in the fishing, there is less competition from bigger fish andthereofre more nutrients from prospecting fecund mothers and reproduction increases, this will have to be kept up as the competition will rise again so the fishing must be maintained
(Lindegren et al., 2011) |
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Term
| What did (Fronhofer et al., 2012) find out about metapopulations? |
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Definition
He mapped the link between different rates of r and the population dispersal, heterogeneity and environmental stochasticity, looked like this...
[image] |
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Term
| What are important factors to remember when considering population dynamics |
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Definition
Habitats are very rarely homogeneous, they are split up and vary a lot from area to area
Populations are rarely continuous in habitats, there will be mixes of populations throughout
Populations have spatial structure, the communities within will be separated by the other communities in the habitat of other species
Variance in habitat leads to variance in population dynamics (different rates of death, reproduction, immigration and emigration) |
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Term
| How does a differing r value effect the population variation around k? |
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Definition
If the r value is high the population will be close to the k value. This is because the population is quick to respond to the changes and can adjust to be close to the maximum carrying capacity.
Low r value means it will fluctuate around the K value.
It is also down to the T value as the time lag means that it takes longer for reproduction phages to be seen in the population |
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Term
| What did (Peterson et al., 1984) discover about population dynamics? |
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Definition
| They found that the time lag of a species, the generation length, was important for mapping the population dynamics as they found the different models that would occur with low, medium and high T values which is shown on the poster above your desk |
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Term
| What is the rescue effect? |
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Definition
| This is when a population with a negative r value is prevented from extinction because of a source population that is connected via dispersal feeding the population with other members as they may go for reduced competition and increased resources so the population continues |
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Term
| What is a metapopulation? |
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Definition
| A group of spatially separated populations of the same species that act at the same level |
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Term
| What is a good example of a good mainland-island system and what is it? |
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Definition
| This is where a mainland is present with a very stable population of a particular species is residing but they are connected to small islands with smaller more unstable populations but they are often rescued by the mainland population via dispersal, even if the r value is negative. |
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Term
| What are the most important factors to remember about resources in an environment? |
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Definition
They are finite.
It is also important to remember that different organisms will require different resources and this will also change at different stages of their life.
This is for a pea aphid
[image] |
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Term
| What did (Stockhoff, 1991) find out about the nutrient quality? |
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Definition
By using gypsy moths, he found that survival was increased with low quality nitrogen foods as the higher the quality of nitrogen the more they were investing in DNA growth and overall body growth. The worse nitrogen food was being used for storage and longevity of life as there was little nitrogen for DNA growth.
Also found that when fed with slightly toxic food, the caterpillars were investing most energy into the defence systems and this leads to lower survival |
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Term
| What did (Hawlena & Schmitz, 2010) discover about nutrient usage under predation risk? |
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Definition
| They looked at grasshoppers to find that more food was eaten under risk of predation however there was a high nitrogen percentage in the faeces as they were using all energy of escape and survival rather than growth so nitrogen was not needed |
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Term
| What did (Kallioniemi & Hanksi, 2011) find out about genetic origin of differences in some animals? |
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Definition
| They looked at the difference in a glanville fritillary caterpillar in two alleles that control a glycolytic enzyme. They found that there was differences in larval survival at low temperatures and then pupal size, clutch size and overall survival |
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Term
| What are the three parameters of long term productive success? |
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Definition
Finite rate of increase - Lambda
Net reproductive rate - R0
Intrinsic rate of increase - r |
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Term
| What is the Euler-Lotka equation and what does it mean? |
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Definition
It is the equation that uses the fitness of females in a population and how this works with the individuals females reproductive rate and how the population grows with these two factors being considered
[image] |
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Term
| What did (Hamil & Beckman, 2009) find out about trade-offs? |
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Definition
They looked at daphnia and there natural predatory, the phantom midge, and they looked at the daphnia survival in the presence of the chemical that the phantom midge releases when it is around.
They found that the daphnia grows neck spines as a defensive strategy but only in the presence of the chemical. Once they have invested energy into the neck spines, they take much longer to develop and reach sexual maturity, lowering their individual fitness in these areas.
This is a model trade-off paper |
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Term
| What did (Gustafsson & Sunderland, 1988) find out about measuring trade-offs? |
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Definition
They observe collared flycatchers and looked at their clutch sizes and how they vary. They manipulated the clutch size to see whether the parent would be able to raise any number of chicks.
They found that the number of chicks a parent had was very specific and they would have the maximum number they were able to raise in their specific environment. Similar to the (McKellar et al., 2013) paper, they birds would have as many offspring as they were capable of rearing to adult hood.
This can be used to describe the specific fitness of an individual |
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Term
|
Definition
This is the idea that 1 gene that controls something specific will also control an unrelated trait.
Antagonistic pleiotropy is the idea that 1 gene will control one beneficial trait but also 1 detrimental trait
Example of this is sickle cell anaemia.
(Carter & Nguyen, 2011) discuss antagonistic pleiotropy in many disease that should have been selected against a long time ago in a good paper |
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Term
| What is the most key point about tradeoffs? |
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Definition
| The idea that all tradeoffs are maximised to increase an individuals fitness |
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Term
| What did (Murry & Cutter, 2011) find out about C. elegans trade off? |
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Definition
They found a gene that controlled increased sperm production in the C. elegans which meant they could produce 500 instead of 300.
However the nematode worm then takes 2.5 hours longer to reach maturity which means the development area of fitness is decreased. |
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Term
| Why is body size important when looking at tradeoffs in fitness? |
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Definition
We can map all terms of fitness relative to body size in the D. melnogaster and therefore we can map out the different tradeoffs that are made in terms of fitness with this individual species and put it onto one big graph.
(Roff, 1981;1986)
[image] |
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Term
| What is phenotypic plasticity? |
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Definition
This is the variation in optimal body size according to various conditions in the current environment
It means that when you put all of fitness in terms of body size, you can then put the size in terms of growth at different ages and then like growth to the resources at different times. This means you can link the optimum body size to the state of resources currently available. Put in a graph here:
[image] |
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Term
| How can diet effect lifespan? |
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Definition
Due to resource allocation, lower quality of diet in animals such as file and rats cn lead to increased longevity. This does not mean their fitness increases as their development and fecundity or lower however they do last longer.
This study was performed by (Mair, 2003) on D. melanogaster |
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Term
| What did (Rauser, 2004) find out about resource allocation? |
|
Definition
|
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Term
| What did (Cartwright et al., 2014) find out about phenotypic plasticity? |
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Definition
| They found by using Mauritius Kestrels, that human farmland had destroyed the kestrels natural forest habitat which has led to higher mortality rates and led to high resource allocation to reproducing early in life to keep r high to balance the higher mortality rates. |
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Term
| What is a very good GM paper to do with optimal tradeoffs? |
|
Definition
(Howard et al., 2004)
Looks at Japanes Medaka fish that were GM with salmon growth hormone. At first the gene spread through the population but then the WT fish developed alternative mating tactics to shut out the bigger medaka fish and the larger medaka fish also experience survival cost and this lead to the GM medaka fish extinction in just 50 years. |
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|
Term
| What are the 6 main factors/events that make up an organisms life history? |
|
Definition
|
|
Term
| Who was right, Medelian genetics or biometricians? |
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Definition
Both.
Phenotype is a mixture of the continuous and discontinuous genetics. It is the build up of both that makes the phenotype. There is also environmental impact on the phenotype too |
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Term
|
Definition
He was a biologist that was on the forefront of the belief that genes were additive and that continuous variation is polygenic in origin.
He also developed the Fisherman Principle whereby he explained why most animals will have an offspring sex ratio of 1:1 and the assumptions that fit most of those models. |
|
|
Term
| What are said to be to factors for building a phenotype? |
|
Definition
Additive effects of all the loci
+ Dominance relationships at each locus
+ Interactions among genes (epistasis)
+ Maternal effects
+ Environmental effects
+ GxE Interactions between genotype and environment |
|
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Term
| How is heritability calculated? |
|
Definition
h^2 = Va / Vp
Va = Variance in the additive effects all the loci
Vp = Variance in the phenotype
Vp = Va [+ Vna ] + Ve [+ Vg*e]
The non additive effects and the interaction between genes and environment are both ignored as they are thought to be negligible or unimportant in this maths |
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Term
|
Definition
It is the ratio comparing phenotypic variation in offspring and how much of it is genetically inherited.
It will be a value between 0 and 1
Heritability of 1 means that a traits variation is all genetic
Heritability of 0 means that a traits variation is environmental and therefore not subject to genetic evolution |
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Term
| What did (Grant & Grant, 2002) find out about heritability? |
|
Definition
They studied darwin's finches and found that the beak size trait was largely genetic however due to a value of 0.9 it is hard to predict future changes with the beak size as it is subject to some environmental change.
For good comparison, the individuals you are looking at must have been through similar environmental backgrounds |
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|
Term
| Why is h2 important in artificial selection? |
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Definition
| It is important to know the heritability of a trait as selection for an extreme of a certain trait can cause heritability of that trait to reach 0 which means there will be no genetic variation amongst strongly selected individuals |
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Term
|
Definition
| It is the idea that the more important a certain trait is to the species' survival, the lower the heritability and lower the genetic variation as it has been strongly selected for as it is so important for the organisms survival. |
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Term
| What did (Gustafson, 1986) create for measuring traits responsible for fitness? |
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Definition
| He studied collared flycatchers and was able to assign a value of r^2 to each trait, with the higher the value of r2, the more important the value was to the individuals fitness. |
|
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Term
|
Definition
| This is the idea that in lekking mating, there are extremely highly selected sexual characteristics that only occur in males where they compete against other males for female selection. |
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Term
| Why is heritability for fitness 0? Shouldn't overall fitness be strongly selected for? |
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Definition
The issue is that there is no gene for fitness and also, the overall fitness of an individual is changed so much by other factors
[image] |
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Term
| What are the 5 theories that explain why fitness is not at a heritability value of 0? |
|
Definition
Theory 1: mutation-selection balance
Theory 2: fluctuating selection
Theory 3: tradeoffs
Theory 4: non-additive genetic variation
Theory 5: sexually antagonistic selection |
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|
Term
| What is the basis for the theory of mutation-selection balance when explaining the maintenance of genetic variation for fitness? |
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Definition
It is the idea that selection removes variation and then mutation puts it back again.
However the rates of mutation are much lower than the rates of selection. |
|
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Term
| What is the basis for the theory of fluctuating selection when explaining the maintenance of genetic variation for fitness? |
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Definition
It is the idea that because the world and the environment is never the same, day to day and year to year, the factors that will comprise total fitness are not the same all the time therefore selection pressures will change.
Each trait has a fluctuating r^2 value in the (Gustafson, 1986) model |
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Term
| What did (Hairston & Dillan, 1990) find out about fluctuating values of fitness? |
|
Definition
| They studied copepods and the switch to diapause to suspend development so that they could avoid heavy predation but still be able to find a mate. They found that due to a very liquid system in which changes occur a lot, the timing of diapause would change throughout the year and year to year. |
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Term
| What is the basis for the theory of genetically-based tradeoffs when explaining the maintenance of genetic variation for fitness? |
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Definition
It is based on the idea that because tradeoffs occur, an individual is physiologically constrained to have all the attributes that impact fitness at it's maximum rate
This is shown in such papers as the (Murray & Cutter, 2011) paper that shows a basic nematode worm tradeoff. |
|
|
Term
| What is the best model to show difference in fitness values and changing environment effects on fitness selection? |
|
Definition
|
|
Term
| What is the basis for the theory of non-additive effects of genes when explaining the maintenance of genetic variation for fitness? |
|
Definition
Fisher first believed that non additive effects of genes were not very important however we now understand genes a little better and understand other gene-gene relationships that are not additive but are controlled by the same gene.
Also maternal effects, GxE interactions and dominance effects are fairly big factors. |
|
|
Term
| Who performed the dyslexia study and what does it relate to? |
|
Definition
(Paulesu et al., 2001)
It relates to GxE interactions as it is a same genetic issue but with differing environments that mean it is not as big as issue |
|
|
Term
| Why is a double mutation sometimes factor with fitness? |
|
Definition
| This is when epistasis is occurring a double mutation leads to lower fitness rather than higher which is not what you would expect |
|
|
Term
| How do maternal effects affect the fitness of an individual? |
|
Definition
(Dantzer et al., 2013) found that in red squirrels, a mother is able to stimulate a faster rate of development in her young if their is a fruitful environment with plentiful resources as the mother wants the young to take advantage of the good conditions.
This can be shown to still work without the plentiful resources by making the mother think the conditions are good by making a lot of population noise so it seems there are lots of individuals around. |
|
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Term
| What is the basis for the theory of sexually antagonistic selection when explaining the maintenance of genetic variation for fitness? |
|
Definition
Direction of selection may be different in different sexes; different sexes may be preferred or be given a dis/advantage due to certain circumstances in the species.
(Forester et al., 2007) looked at red deer and how if the father is in good fitness, they will have higher fitness males and lower fitness females |
|
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Term
|
Definition
| The study of the diversity, the classification and the history of organisms with the evolutionary links between them |
|
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Term
| What is the main aim and role of taxonomy? |
|
Definition
| Classify each organism into clear groups and be able to identify each group and sub groups and species based on specific attributes that you can follow on a key |
|
|
Term
| What is Ridley's method to analyse the evolutionary relationship between two discrete characteristics? |
|
Definition
This is for DISCRETE characteristics.
You can map the attributes onto a phylogeny and note where there is a positive or negative relationship.
However for Ridley's method you can't count species for species, you must only look at the independent common ancestors whereafter a change will occur from that ancestor.
Use chi squared test to test for significance |
|
|
Term
| What are sister groups on a phylogenetic tree? |
|
Definition
These are groups that share a common ancestor and the differences between the groups will be independent of the other changes on the tree.
Where a split occurs, the two groups that split off become sister taxa
You can use these to compare the differences between sister groups but only for CONTINUOUS CHARACTERISTICS |
|
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Term
| When looking at a phylogenetic tree, what is the difference between a non-directional and directional contrast? |
|
Definition
Non-directional is just measuring the difference in continuous characteristics between different sister groups in a phylogenetic tree. This is how you can measure difference in a non-directional way. This ensures independent sample points from each other sample point.
Directional is measuring the difference in characteristic point along the branches of the phylogenetic tree. Measuring the difference between one branch and its previous ancestor and so on. You get more relationships than non-directional contrasts however you must know more information about the ancestors and the organisms involved. |
|
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Term
| What is Richard Southwood famous for? |
|
Definition
He wanted an evolutionary periodic table. He created something similarish to be a good start for life history comparison.
[image]
This links to r and K selection
r =fast
K = slow |
|
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Term
|
Definition
r is the fast, quick and short life history. They have ephemeral habitats (they are unpredictable and can disappear)
K is slow and long with smaller broods. They have more stable environments |
|
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Term
| What did (Mueller et al., 1991) find out about r and K selection? |
|
Definition
| They studied drosophila and found that when you adapt the drosophila to a certain density of environment, they do well in that environment but when you change the environment density from low to high or vice versa, they suffer. This shows that r and K selection are life history traits that organisms adapt to. |
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|
Term
| What is a key point of r and K selection? |
|
Definition
When an animal is from high density population, the fittest have lower numbers of offspring, when an animal is from a low density population, the fittest will have higher numbers of offspring.
This was shown in a great tit study from (Saether et al., 2016) |
|
|
Term
| What is the third selection type in the r and K selection? |
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Definition
| It is called A, it does not fit the perfect model and it is for organisms that live in awful environments like deserts or the arctic. They have unhospitable environments. They are in severe but predictable environments where the organisms are just attempting to survive. |
|
|
Term
| What is Southwood's grand solution? |
|
Definition
| This is a take on the r and K selection that includes the A selection too. [image] |
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|
Term
| Who came up with the niche theory? |
|
Definition
Joseph Grinnell in 1917 when talking about the Californian thrasher.
It has a restricted range and could only live in certain environmental conditions
It was based on the idea that because it had specialised so much there was natural selection for intraspecific adaption in different parts of the species range but no other species would have exactly the same range and abundance/distribution through the range |
|
|
Term
| What is the niche theory graph? |
|
Definition
[image]
It explains that a species must be specifically adapted to their specific environmental conditions so much that they have enough resources to achieve enough fitness to reproduce |
|
|
Term
| What is a species distribution limit? |
|
Definition
This is the environmental limit which is constrained to where the organism can replace itself through reproduction.
If it cannot replace its population in an area, that is not an area in which is adapted to live in |
|
|
Term
| What is a meta analysis and what is a good example? |
|
Definition
A meta analysis is when you take a lot of studies and that are all looking at the same thing and then you compare when you put them all in the same currency
(Hargreaves et al., 2014) looked at various species analysis to look at individual fitness in different distances from their desired range |
|
|
Term
| What is the ecological meaning and importance linked with the phrase 'there goes the vicar'? |
|
Definition
This was said by Charles Elton who was talking about the niche theory.
It is the idea that when you see an organism, you should not just think about what that organism is, but also where it has come from, what it does, it's place in the natural community, what it interacts with and the relationships around it.
(Elton, 1927) |
|
|
Term
| What is an N dimensional hypervolume? |
|
Definition
This is the phrase used to describe the range of an organism when looking at its optimal range in three variables.
If you look at a a birds range you may compare, the foraging height, seed size and the time of day it tends to feed. Would then get a graph like this.
[image] |
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Term
| What is a fundamental niche? |
|
Definition
This is the perfect range where the organism would live if no other species where around for competition or such. This never truly exists due to the existence of all species simultaneously.
(Hutchinson, 1957) |
|
|
Term
| What is a realised niche? |
|
Definition
This is the true niche of an organism.
It is the idea that because of other species, overlap of niches will occur.
Organisms will occupy similar spaces, eat similar food, take similar resources. Never identical but similar.
A realised niche is when all organisms in an area have settled into their balanced niche
[image] |
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|
Term
| What is Gause's principle/law? |
|
Definition
| This is the idea that no two species that will be competing for the same resources will ever stay at a constant population. The competition will arise and therefore the dominant species will push the subordinate species into a new niche. |
|
|
Term
| What is (Hutchinson, 1957)'s view on natural selection? |
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Definition
| He views that natural selection will select for the ability to compete (straight fittest) or the ability to avoid competition (quick adaption) |
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|
Term
| What is the difference between Grinnell and Hutchinson's niche theories? |
|
Definition
Grinnell believed that each species will derive its own niche and this arises through natural ability to survive in different ranges and have different preferences. This is an autecological view whereby there it is not competition driven but just the natural species occurring in different niches
Hutchinson believed that the the niches were brought about by interspecies competition and that it led to species having to have different niches that were equidistant in a sense so that they would each have enough range and resources to survive. He also believed there were no vacant niches, that niche competition led to environment niche saturation. |
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Term
|
Definition
This is the idea that when there are multiple similar species in an environment, they will have similar niches but selection will reduce the size of the overlap of niche due to the fact that each is more specialised to their specific optimum range even though they are still able to exist in areas away rom their optimum.
It is regular spacing between intra species niches |
|
|
Term
| What is niche complementarity? |
|
Definition
| This is the idea that species that will exist in similar niches in one environmental dimension will differ along a different dimension. This limits the overlap between two different species |
|
|
Term
| Do Vacant niches actually exist? |
|
Definition
Yes they do, famous case of the lack of bracken feeding insects in Hawaii is true where they should be some but none exist.
(Walker & Valentine, 1984) looked into the number of empty niches there possibly could be and found that a relatively large number existed and many more may have existed if it was not for human dispersion. |
|
|
Term
| What is the world is green hypothesis? |
|
Definition
This is (Hairston et al., 1960) when they looked at the basics that because the world is green, how come there are not herbivores everywhere? They are not limited in food but they do not kill the plants they eat, the plants continue to exist everywhere.
The idea is that a balance exists in the communities:
-Decomposer populations limited by food supply
-Plants limited by the supply of resources
-Herbivores limited by predation
-Predators limited by their food supply
Bottom Line: No competition between herbivores |
|
|
Term
| What is the inadequate environment hypothesis? |
|
Definition
(White, 1993) talks about the idea that food shortage will govern all of the trophic levels, even the herbivores, due to differing food qualities (especially nitrogen content (Pimental & Pimental, 2003))
It believes that because the food is limiting factor in areas, it is rarely competition that will in fact shape the environment
Bottom Line: No competition between trophic levels |
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|
Term
| What are the different mechanisms of competition? |
|
Definition
| Consumptive - Competition by consuming limited resources Pre-emptive - Competition for passive living space Overgrowth - When an organisms will physically grow over another organism to take light and resources to kill off competition and take place. Chemical - Chemical use to cause disadvantageous effects to the other competing organisms Territorial - Total control of entire patch to stop another competition from arising or accessing the resources inside Encounter - Physical encounter competition such as attacks, theft or manipulation |
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|
Term
| What is the consumptive competition mechanism? |
|
Definition
This is the idea that competition arises from the consumption of limited resources. This is the most common competition unless in marine environments
Can be tested by removal of a species from a habitat and then the competing species will begin to take advantage of unused food source but then when put back the niches will become realised again. |
|
|
Term
| What is the pre-emptive competition mechanism? |
|
Definition
| This is the idea that there is competition for passive space, living space. An organism will move into unused space to have a larger area so that another species will not move in. |
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|
Term
| What is the overgrowth competition mechanism? |
|
Definition
| This is when an organism will physically grow over another to limit the organism's ability to catch resources or light. This will occur with sessile organisms like mussels of barnacles Famous experiment from (Connell, 1961) about two barnacle species |
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|
Term
| What is the chemical competition mechanism? |
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Definition
| This is when an organism will use chemicals to disadvantage another species that is competing Use often by bacteria which will excrete antibiotics to kill competition Also in insects where they will create irritant chemicals to get rid of other organisms (LeBrun et al., 2014) |
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|
Term
| What is the territorial competition mechanism? |
|
Definition
| This is when you will take over an entire territory/patch and claim is as own and protect. This will allow no other organism to inhabitant or colonise in that area. (Cole, 1983) experimented with 4 different ant species that had colonised entirely different small islands. He tried to introduce different species into either independent species islands or island with coexisting populations. A new species could never colonise and survive in a new island |
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Term
| What is the encounter competition mechanism? |
|
Definition
This is physical meeting of species. Can be theft, damage, distraction or other physical encounters but this is direct physical encounter competition
(Morse, 1981) performed study on hoverflies and bumble bees and their encounters on flowers. Found dominance of bumblebees in the interaction where overfills will leave if bumblebee comes over. |
|
|
Term
| Which habitats will have the most prevalent competition mechanism in play? |
|
Definition
Marine - Pre-emptive
Terrestrial - Consumptive
Fresh water - Consumptive |
|
|
Term
| What is different about Marine environments compared to fresh water and terrestrial in the idea of competition? |
|
Definition
Marine will not abide by the HSS Green World theory
There are few large predators and very many herbivorous fish with much more limited plants and fauna therefore competition between predators is less than that of the herbivores |
|
|
Term
| What did Gause use as his experiment to study his principle? |
|
Definition
He used three different ciliate protozoans
- P. caudatum
- P. aurelia
- P. bursaria
He looked at their co existence in limited mediums when grown together and their ability coexist or not coexist. |
|
|
Term
| What happened in Gause's experiment between P. aurelia and P. caudatum? |
|
Definition
The P caudatum would be outcompeted and would not be able to co exist and would become extinct in the medium.
This was found to be because of chemical competition form the P. aurelia.
This is because they have the same niche and one is dominant |
|
|
Term
| What happened in Gause's experiment between P. bursaria and P. aurelia? |
|
Definition
| Stable co existence whatever ratio you put them in but the populations would always go to the same proportions, as the P. aurelia was dominant however the P. bursaria was able to exist under the sediment due to symbiotic algae which it got its nutrients from and air. The P. caudatum can't do this and that is why it dies in both experiments This is because P. bursaria is able to occupy a secondary niche that is not occupied |
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|
Term
| What are the Lotka-Volterra equations? |
|
Definition
These are models that are used to show the relationships between predator and prey populations. They are a take on the Lotka/Lotka-Euler equation where the logistic population growth interacts with the carrying capacity and current capacity of that species.
[image]
They are the same but they just include a competition parameter and the N/K value of the competing species.
The competition parameter is the a21/a12 part and this value will obviously change for each different species relationship |
|
|
Term
| What is the Isocline equation? |
|
Definition
This is equation we use to describe the relationship when the population growth of the two species is 0
[image] |
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|
Term
| What does the plot look like for the isocline zero growth curve of the two interacting species and what does this mean? |
|
Definition
[image]
It shows the balance of the population when the values of r are 0. It is basically saying that the population of one species is the carrying capacity of that species minus the (competition from the other species multiplied by the population of the other species) |
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|
Term
| How can you tell when looking at a Isocline graph which species will be dominant in a population if the lines do not cross? |
|
Definition
When there is no line crossing, the line outermost will be the most abundant and will dominate e.g.
[image] |
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Term
| How can you tell when looking at a Isocline graph which species will be dominant in a population if the lines cross? |
|
Definition
There can either be stable or unstable equilibrium.
[image]
When the K values fall inside the outmost lines, there will be a stable equilibrium in the system. It means that intra specific competition is greater than that of inter specific competition
When the K values will fall as the outermost lines, it represents unstable equilibrium and it will depend on the starting population to which species will dominate.
It means interspecific competition is greater than the intra specific competition |
|
|
Term
| Which competition is greater when there is unstable equilibrium in a system between two species? |
|
Definition
| Inter specific competition is a greater force than intra specific. |
|
|
Term
| What is is so useful about the isocline growth line? |
|
Definition
| It means you are able to predict the competition in an environment if you are able to calculate all the variables and their importance. |
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|
Term
| What other factors could effect the isocline growth competition? |
|
Definition
Environmental conditions such as temp, pH and such
In these cases there will be an intermediate zone which is unpredictable and can be down to genotypic selection and random chance.
[image] |
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Term
| Are the isocline graphs so simple in reality? |
|
Definition
| The graphs actually contain curved lines due to the competition variables changing in severity with different populations, they do not change on a linear scale but exponentially. |
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|
Term
| Does Niche overlap = competitive effect? |
|
Definition
Yes, niche overlap will induce competition and competitive effect does arise as in a lot of cases the species will not be able to stable coexist even a bit in many cases however in other cases, stable coexistence is not foreign
(Hogstedt, 1980) |
|
|
Term
|
Definition
This is the axis to measure how close niches are to each other. Usually not linear
Will measure amount of overlap two or more niches will have |
|
|
Term
| What is different about the niche of a specialist and generalist? |
|
Definition
| Generalist has a wider niche |
|
|
Term
| What is the critical point of niche overlap? |
|
Definition
d/w=1
[image]
This is when there is maximum number of coexisting species in a community. Will be an optimal number of individuals in each species in that community based on resource distribution. |
|
|
Term
| Why are niche overlaps rarely optimal/maximal? |
|
Definition
Fluctuating resource distribution
Environmental K value changes
Stochasticity
There are more generalists in the community than predicted |
|
|
Term
| What is the area under the curve of overlap at maximum niche overlap? |
|
Definition
|
|
Term
| What happens to the minimum niche overlap as the resources become more variable? |
|
Definition
| The minimum will increase as the resource variability increases |
|
|
Term
| What is the magic number in ecology and what does it mean? |
|
Definition
1.3
This is the minimum ratio of differences (size, food size) between coexisting species.
e.g. Different foods that were specialised by different birds on an island were all 1.3cubed times the size of the next smallest food eaten by a different bird.
e.g. 11 coexisting water boatmen species all had proboscises 1.3x bigger than the next smallest |
|
|
Term
| What is the idea of minimum difference in niche species? |
|
Definition
This is the minimum difference that two species will have to be to each other to be able to coexist.
There food must also be minimally different or above for the happy coexistence to take place |
|
|
Term
| What is character displacement and what is an example? |
|
Definition
| This is the idea that a two similar species will have more similar characteristics when both solitary however when both present in a population, their niches will overlap and therefore will push the traits further apart and minimise the niche overlap. Geospiza fulginosa and G fortis had similar bill length when found solitary but with interspecific competition the bill lengths changed to 12mm and 8mm respectively Means species become more specific due to interspecific competition. Divergence in organisms |
|
|
Term
| What does competition between species lead to? |
|
Definition
|
|
Term
| What does 2d niche packing look like |
|
Definition
It it like the birds eye view of the niche curves on a niche axis
[image]
Food type and habitat are the usual major axes
Means you can predict to more number of species in an environment |
|
|
Term
| What is the maximum overlap model with 2d niche packing? |
|
Definition
| A hexagonal overlap model where one niche will overlap with a maximum of 6 other niches |
|
|
Term
| What is a good example that backs up the idea that increase in niche numbers will give decrease in mean niche overlap? |
|
Definition
The lizard study by (Rappoldt & Hogeweg 1980)
[image]
It uses a limiting factor of water availability and this is used to show the different number of lizard species in different habitats with different water availabilities |
|
|
Term
| What else did Hutchinson come up with other than the saturation of niches theory? |
|
Definition
| He came up with the idea of 1.3 being the sacred ratio |
|
|
Term
| What are HSS's and White's theories about predation? |
|
Definition
HSS believes that predators will control the herbivore population but no other intertrophic level relationships matter
White believes that all populations are controlled by their food availability and therefore a bottom up trophic level control |
|
|
Term
| What is Menge's theory of trophic level predation? |
|
Definition
| He believes that the importance of predation should increase the lower down the trophic level you get |
|
|
Term
| What does (Sih et al., 1985) backup about species predation importance? |
|
Definition
| It backs up Menges belief that the importance of predation increases as you go down the trophic levels. |
|
|
Term
| What does (Salo et al., 2010) meta analysis of terrestrial vertebrates tell us? |
|
Definition
Tells us that the territorial predators will effect the prey a degree of 0.6.
This means that when the predators are removed, the prey will grow abundantly to 1.6 of their predatory controlled population |
|
|
Term
| How do different predators effect their prey populations differently? |
|
Definition
The different predators will effect the different populations of prey because of the amount and the age of the prey that they hunt.
Adult and yearlings will be a big impact.
Calves will mostly die anyway so not a huge impact if they die on the population |
|
|
Term
| How can predation effect selection pressures? |
|
Definition
Different sizes of prey may be preferred by the predator. Therefore prey size selection is seen and when the predator is present there will be a much stronger skew towards the undesired prey size compared to when there is no predator present
This is shown with falcons and great tits by (Vedder et al. 2014) |
|
|
Term
| What are unexpected events? |
|
Definition
These are when there are unusual predation effects from linear trophic levels down the trophic levels.
However the effects will occur because of different competition between different species in the food web.
It is because species will effect others in the food web and community, not just the trophic level below and above it |
|
|
Term
| What is a keystone predator? |
|
Definition
| Predator that keeps diversity and population in check and controls dominance of prey items |
|
|
Term
| What is enemy free space? |
|
Definition
| This is the idea that indirect competition form predatory free space. Not direct competition but just looking for areas of no predation |
|
|
Term
| How did Gause experiment on the predator prey systems? |
|
Definition
He was able to look at the ciliate protozoans an try to create an equilibrium in a closed system.
The predator would eat all the prey and then starve to death or prey would hide and then grow without predation.
Only stable environment was when he simulated immigration by adding individuals, simulating a rescue effect |
|
|
Term
| What lab study will show predatory prey cycles? |
|
Definition
| Bean weevil and parasitoid will cycle naturally |
|
|
Term
| What is the classical predator prey cycle? |
|
Definition
Lynx and snowshoe
Hare will cycle ever 10-11 years
Lynx will peak 1-2 years after the hare.
This cycle will occur in one area. The population will actually be constant throughout different areas in Canada which shows spatial significance of the hare cycle |
|
|
Term
| What is the other effect of lynxes that will effect the snowshoe hare population? |
|
Definition
| The Lynx predation risk will effect the female hare stress levels and this will then create delayed fecundity and they have fewer offspring |
|
|
Term
| What can the abundance distribution and predator prey cycle be compared with? |
|
Definition
Dropping a stone in a pond and having the rippling waves. This is how the cycles work in an area, the peaks of population will move but in one area, the population will seem to cycle.
This is due to different movement of the organisms |
|
|
Term
| Why are parasitoid-host model good to use for cycling predation models? |
|
Definition
These are used as the parasitoid will often not have males and if they do they are not the individuals parasitising a host organism
Also easy to predict that the parasitoid will lay an egg in a host and one female will emerge from the dead host |
|
|
Term
| What is the host equation in the parasitoid host general model? |
|
Definition
[image]
Not differential equation due to discrete populations
It is the reproduction of the population x the number of individuals x the number of hosts not parasitised |
|
|
Term
| What is the parasitoid equation in the parasitoid host equation general model? |
|
Definition
[image]
Not differential equation due to discrete populations
It is the number of hosts x the parasitoid young per host (usually one) x the proportion of hosts that ARE parasitised |
|
|
Term
| What assumptions does the Nicholson and Bailey model use? |
|
Definition
- Synchronised generations
- One parasitoid per host
-Egg limitation (this reduces search efficiency and limits the average number of attacks per host) |
|
|
Term
| How do you stabilise the Nicholson-Bailey model? |
|
Definition
Add the component for non random searching into the searching efficiency part.
[image]
This is accounting for mutual interference and stabilises the model but does not fully fix it |
|
|
Term
| What component would not fix the Nicholson Bailey model? |
|
Definition
Adding a component for the prey density. This would change the value for a in a wrong way so the stability would move in the wrong direction.
Non random searching is the component used instead |
|
|
Term
| How do you fix the Nicholson-Bailey model once you have added the mutual interference bit? |
|
Definition
Add non random distribution into the model.
Just by applying the model to non random spatial structure of the environment.
This means patches in an area either static or dynamic. This will be species dependent but the distribution is often organised.
[image]
Rescue effect is the importance |
|
|
Term
| What is the overview of the Nicholson Bailey model? |
|
Definition
Predator Prey relationships are highly unstable.
2 factors that will add stability are:
-Mutual interference: Effect of aggregating predators in areas of high prey density
-Stabilisation caused by metapopulation structure and movements within the metapopulation |
|
|
Term
| How much plant do herbivores eat? |
|
Definition
Terrestrial: 10-20%
Aquatic: >80% (there are much less aquatic herbivores) |
|
|
Term
| Why is being a herbivore hard? |
|
Definition
Hard to digest the vegetation
Often use gastroliths in the gizzard in birds
Usually will require specialised organ in the gut to produce microbial fluid to break the hard plant tissue down.
Some things still indigestible: lignin, silicified fibres |
|
|
Term
| How do insect herbivores digest their food? |
|
Definition
| They will often be very specialist and will create specialised microbes to breakdown specific plants |
|
|
Term
| Why are plants so hard to digest? |
|
Definition
Because they have very good defences.
It is a very selected trait, plant defence.
Mechanical
Physiological
Chemical
Phenological (Seasonal pattern of growth to avoid predation) |
|
|
Term
| What is the real reason for HSS world is green hypothesis? |
|
Definition
| HSS world is green hypothesis is because just because the green stuff is plentiful and there are loads of herbivores, not much of the green stuff is not digestible |
|
|
Term
| What are examples of plant defences? |
|
Definition
Trichomes, tree bark, spines, leaf toughness
Cellulose in the leaf leading to leaf toughness. This is because cellulase is very rare in the environment throughout species
Some fungi will have it |
|
|
Term
| What are the important structures in vegetation that will give the plant its strength? |
|
Definition
Cellulose:
80% of dry weight
Cell wall
Lignin:
Binds to cellulose
Indigestible
Binds enzymes
Tannins:
Large molecules will bind digestive enzymes and prevents them working
Silica:
In cell wall
Acts like microscopic sand
Will cause tooth wear |
|
|
Term
| What is the limiting nutritional quality of plants? |
|
Definition
| 1/10 of the nitrogen that is present in meat |
|
|
Term
| What are good plant defences other than structure? |
|
Definition
Toxins
Secondary chemicals found in plants that will cause issues in the consumers.
Primary toxins are terpenes |
|
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Term
| What is the difference between obvious and cryptic plants? |
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Definition
This is when a plant, like a tree, will be obvious and easily found and predated on
A small niche herb will possibly escape herbivory due to the cryptic hidden nature of these plants.
Obvious plants require different more generalised defences
Cryptic will require specialist defences including specific toxins
(Feeny, 1970s) |
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Term
| What was he evidence used for Feeny's cryptic/obvious plant hypothesis? |
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Definition
He looked at a moth that will feed on an obvious Quercus robur tree.
He found that some years that the forest would be completely stripped by the moth. This was due to the timing of the hatch emergence.
Too early --> Caterpillars starve
Too late --> Leaf defence too strong
Right time --> Perfect good resource distribution and this leads to optimal population growth of the caterpillar/moth.
The leaf loses protein and gains tannin when it develops which stunts caterpillar growth |
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Term
| How is Wild Mustard a good cryptic plant example? |
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Definition
Short lived herb plant
Has qualitative defence of the sinigrin toxin that will cause death in consumer at extremely low quantities (0.1%)
Black swallowtail will be effected by this
Two 'cabbage white' species are specialised to eat this Mustard plant. These butterfly species will use the specialised sinigrin as a signal for host plant location rather than a toxin.
This is specialisation in anti-toxin defence. |
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Term
| What is the most common detoxification enzyme found in insects? |
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Definition
Cytochrome p450
It is a mixed function oxidase
Present in vertebrate livers and insect guts
Mice have much more efficient cytochrome p450s in their gut than humans |
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Term
| What is the organisation of the ungulate herbivore detoxification distribution? |
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Definition
Specialist: e.g. Gerenuk - impala
Will have narrow mouth and is fairly selective about what it will eat, mainly seeds and easily digestible foliage. Will have a small rumen but have to migrate around to find food sources as they will degrade a patch quickly
Grass grazers: Wildebeest
Specialist for abundant material
Will follow green pasture
Will require metabolism to breakdown grass and thats it
Generalist: Buffalo
Large mouths
Will eat the silicified parts of the grass
Will not migrate to follow, will just eat poorer quality food and loose weight during dry season |
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Term
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Definition
| It is the area in many herbivorous animals that will contain many microbial contents to aid digestion of the plant material |
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Term
| What is the red queen hypothesis? |
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Definition
This is the idea that all the communities in ecology will have to adapt continuously to be able to stay in the game.
The plants and herbivores will continuously coevolve to be able to stay alive |
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Term
What is the good coevolution example?
(Berenbaum) |
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Definition
The wild parsnip and the parsnip web worm herbivore.
The parsnip produces toxins that it will pump into its seeds to prevent predation of its seeds. The toxins are known as furanocoumarins
this strong selection pressures is aided by the furanocoumarin level and cytochrome p450 levels are both highly heritable and therefore subject to high natural selection.
(Berenbaum) study |
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Term
| What are the rules for coevolution to occur? |
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Definition
1. Genetic variation for characters in both plant and insect
2. Each species must act as a selective force on the other (i.e. affect fitness)
3. Each species must respond to selection |
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Term
| Why do all plants not have all the toxins defences? |
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Definition
It is costly to produce and make the toxins.
When the plant is not at risk of predation, the plants will not have the toxins present, they will still produce same number of seeds but no toxins made.
(Berenbaum) |
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Term
| How important is the detoxification component of a herbivores metabolism? |
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Definition
The most important
In a study by Berenbaum, she found that detoxification is the last thing to stop being produced by the insect in the face of starvation.
This must be without it, it cannot feed at all. |
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Term
| Is detoxification ability of different toxins phenotypically plastic? |
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Definition
| Yes. Any webworm could not be taken and put in an area of different toxins. Each popualtion is specialised in its environment and host plant. It would need to adapt to be able to deal with the toxins however in closely related species this is ohenotypically plastic. (Berenbaum) |
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Term
| How did Berenbaum show coevolution of the web worm and the Pastinaca genus plants? |
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Definition
| Showed that before introduction of the web worm herbivore, the plants had low levels of toxins however after introduction, the plants rapidly increased their toxin levels in the plant, mainly the seeds. This shows evolutionary arms race in action |
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Term
| What is a tritrophic interaction? |
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Definition
| This is when an organism will use another organism to its advantage in prey or predator relationship |
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Term
| What is a good example of a tritrophic interaction? |
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Definition
Particular caterpillars will feed on Nicotina plants because they 'exhale' a nicotine odour and chemical from their spiracles which will deter the spider which would natural predators of the caterpillar (Kumar et al., 2014)
(Thaler, 2002) looked at the interaction that a plant that has been bitten by a herbivore will have on the natural enemy of the herbivore. The plant will release chemical signals to the environment which will, attract predators to prey on the herbivore |
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Term
| What is a good example of the phylogenetic tree coevolution of the toxin arms race? |
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Definition
Between Milkweed beetles (Tetraopes spp.) & host-plants (Asclepias spp.)
[image]
Host plants are just competing for enemy free space to create newer more severe toxins
(Farrel & Mitter, 1998) |
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Term
| What is the difference between Müllerian and Batesian mimicry? |
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Definition
Müllerian is when you have many unpalatable species that are all similar in look
Batesian is when you have noxious model and palatable mimics.
Palatable must think about density difference as the predator must assume non palatable when looking at the pattern |
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Term
| Why is imperfect mimicry often arising? |
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Definition
This is because the mimics will all get some degree of protection from looking similar. It should be driven by stronger and stronger selection. However: The nastier the model, the further away the mimic can look from the model
The worse the model is, the more memorable it is in the predators mind |
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Term
| What does Aposematic mean? |
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Definition
Means that it is advertising that it is actually nasty.
It is the actual advertisement that you see, the colour |
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Term
| What are the main mimics in Europe? |
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Definition
Syrphidae
The hover flies
They will copy Bombus, Apis and Wasps |
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Term
| What is the relationship of mimicry accuracy and noxiousness? |
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Definition
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Term
| Why are wasp mimics not always very accurate? |
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Definition
| Because wasps are very noxious, they will have a more memorable model |
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Term
| What are the standard features of hoverfly mimics? |
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Definition
[image]
The very accurate mimics will also not behave similarly to the mimicked model |
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Term
| What is the best explanation for mimicry accuracy and who was it from? |
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Definition
(Sherhatt, 2002)
[image]
It says that Position depends on relative noxiousness, densities of models and mimic, timing of coexistence |
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Term
| What is a reductionist and what is their theory? |
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Definition
This is an ecologist who believes that the ecology and events in a system are all due to lower level reasoning. Community life is due to the relationships with individuals and individuals are controlled by their physiology.
They also only assume that meta populations, populations. individuals and species are the main factors in play
Not the ecosystem, community or meta-community |
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Term
| What is the Gaia hypothesis? |
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Definition
| This is the idea from James Lovelock that the world is free living and regulating and naturally it will just look after itself as all things live in harmony |
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Term
| What is fundamentally different about animal and plant ecologies? |
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Definition
Plant ecology does not consist of communities. There is no such evidence to back up the idea of the communities and such
Animal ecology includes interactions at a community level |
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Term
| What is the fundamental meaning of meta? |
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Definition
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Term
| How many hoverfly larvae are aphid predators? |
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Definition
| Around 40% of the Syrphidae family are aphid predators |
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Term
| What are the different levels of specialisation in ecology? |
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Definition
[image]
Going --> that way
Means each generalised level can be broken down into specialised groups.
Can have generalised all the way through however |
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Term
| What two species were used as an example to show generalised species having patterns of preference? |
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Definition
Episyrphus balteatus hoverfly
Syrphus ribesii hoverfly
In Notts, Cardiff and Czech, they all show patterns but also different preferences for different plants to lay their eggs
Specialised preference for oviposition at individual level |
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Term
| What should be seen when looking at egg placement and offspring success? |
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Definition
The preferred areas of egg placement and hatching should have higher levels of offspring success
This preference for different ovipositioning choice is linked to individual specialisation as this may change from individual to individual even in a small population.
This was seen the the Episyrphus balteatus and the Syrphus ribesii hoverflies |
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Term
| What is the simplest form of bottom up effect we looked at? |
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Definition
This was the simple relationship between the correct aphid and the Syrphid that was finding the correct oviposition
The aphid quality and type did matter |
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Term
| What is Brassica and what is special about it? |
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Definition
| This is the mustard plant family and they will invest a lot into producing glucosinolates. These are used for defence usually against disease and pests |
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Term
| Will host plants effect the food web of higher trophic levels? |
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Definition
Of course, the host plant may be very different, even similar species will have be differently preference by consumers (e.g. like aphids).
In one case we look at two mustard plants what create different levels of glucosinolates. Then plant specialists will be able to use the plant poisons/toxins like high glucosinolate levels and then utilise them for own use. |
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Term
| How will environment quality effect a Syrphid oviposition choice? |
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Definition
With bottom up tri/multitophic effects.
The environment quality will effect the health of the host plant which may not be able to grow as well in poor conditions and create less toxins. This will leave less issue for generalist aphids to live on the plant an then hoverfly with preference to this generalist aphid species will many be able to lay eggs onto a plant it would not usually be able to due to poor plant conditions |
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Term
| How can Syrphid ovipositioning choice effect ladybird ovipositioning choice? |
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Definition
| Due to intratrophic level competitive effects, both larvae are aphidophages and therefore neither will lay eggs where many of the competitive species eggs are as to increased possible fitness of their offspring |
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Term
| How can aphid host plant effect the mortality of Syrphids by parasitoids? |
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Definition
| The parasitoid will search for the correct host plant, then look for the aphids, then the Syrphid larvae in which to lay their eggs. |
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Term
| What is a hyperparasitoid? |
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Definition
| This is a a parasitoid that will lay eggs in the larvae of other parasitoids that are the parasites of insects |
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Term
| What is the good looking food web with many different multitrophic relationships shown? |
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Definition
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Term
| What does (Grinath et al., 2012) show about triptophic effects and relationships in a food web? |
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Definition
When looking at Ants, membracids and tree reproduction.
They found that the presence of ants has a poor effect on the plant reproduction as they have such a positive effect on the aphids by deterring the natural aphid predators, that the aphids then have a negative effect on the plant reproduction |
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Term
| Why is understanding food webs important? |
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Definition
| You must understand all the relationships in the community/habitat and in the food web before you are able to predict or assess anything due to possible misunderstanding and misplaced blame on some factors |
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Term
| What are jasmonates and pheromones and when are they used in a food web? |
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Definition
Jasmonate is a chemical that a plant will release to attract aphidophages to prey of the aphids to increase fitness
Pheromones are released by the aphids to attract ants which will prey on the natural predators of aphids |
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Term
| What is a community (predator-prey) matrix? |
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Definition
This is when you will take all the organisms in a food web and then show the predator prey interactions in the environment and what preys on what.
[image] |
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Term
| What did (terHorst, 2010) show about effects of organisms in a manipulated system? |
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Definition
[image]
It shows how the different populations will be able to coexist in a community with different relationships in show |
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Term
| What has more complex food networks, old growth forest or logged forest? |
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Definition
Old growth.
When you log a forest you will lose many connections in the food web. New ones may be made but ultimately more are lost |
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Term
| What is a trophic species? |
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Definition
| When looking at food webs, trophic species is a group of species that will be performing the same role in the community. |
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Term
What is this equation representing?
[image] |
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Definition
This is showing the connectance in a particular habitat.
It is a proportion of how many links we actually see compared to the number of theoretical links that there could be
[image]
S = no. trophic species
L = no. actual links
C = connectance
Can add the parameter 'i' which will show how strong the connection actually is between the two trophic species |
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Term
What are the general properties of food webs?
And who coined them? |
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Definition
- Connectance is fairly constant throughout different sizes of food webs
- Constant predator to prey species ratio
- Food chains short. (Tends to be 3-4 with max of 5, this is to do with productivity and the 10% efficiency of nutrient removal from level to level. With plentiful bottom resources, there may be more links in the chain
-Compartmentation occurs
Guilds (e.g. ‘chewers’) remarkably constant in relative proportions
(Lawton, 1989) |
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Term
| What is a good example to back up the constant connnectance in all sizes of habitat? |
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Definition
| Ants on various different sizes of island. The bigger the island, the more connections there actually were however the value for connectance was very similar on each. |
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Term
| What is a good example to backup the compartmentation of food webs? |
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Definition
Leaf miners (many insect larvae e.g. lepidoptera and diptera) and their preferred host plant.
It shows that sets of insects will prefer sets of plants to feed on.
There is also relationships of compartments of the parasitoid and the leaf miners.
This is when you get this idea
[image]
With each box being a statistically significant box |
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Term
| What is a good example of the importance of interaction strength in food webs? |
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Definition
| (Paine, 1992) looks at a marine food web with chitons and sea urchins as example organisms and find that the interaction strength of these organism leads to a much better understanding of the food web and the community ecology |
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Term
| What did (Ketano et al, 2015) find out about food web relationships? |
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Definition
| Found that the more diversity there is in a food web, the more stable the food web is |
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Term
| What is the basic relationships between larger communities and smaller more specific communities? |
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Definition
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Term
| What did Bjorn Brembs (2010) look into about human and vertebrate brain function? |
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Definition
| He looked into free will and the idea that went against genetic determinism. This is because he contests the idea of free will as a false state but environmental and individuals factors come into play which leads to difference in genetic expression of various factors which creates the loss of the majority of fixed actions |
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Term
| What records do we use for human studies of ecological selection? |
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Definition
Lutheran records.
The lutheran church recorded all the details of the parish life that occurred including lives, deaths, offspring, marriage, fecundity etc.
With these records we have seen that human culture shows many similarities with selection in other nature |
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Term
| What differences do males and females show in heritability of human LH traits? |
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Definition
| It has ben found that traits such as fitness, LRS and fecundity are highly heritable in women and not very heritable at all for men. This is because men's traits are usually very much dictated by maternal effects rather than the genetics. |
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Term
| What age preferences do males and females have for their partners? |
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Definition
Males like younger women
Females like older men
(Fieder & Huber, 2007) |
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Term
| What is a good example of two specific ESSs from the same species? |
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Definition
In Oncorynchus kisutch, their are two populations of males that will grow to different sizes and have different mating tactics. This is relevant to LH traits as it is a division of the species ESS throughout that both coexist to have the same average LRS
(Gross, 1985) |
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Term
| What is an example of a flexible ESS? |
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Definition
Ideal free distribution in aphids when picking leaves for habitat and ovipostioning
Better the leaf, the more can afford to share it, this graph:
[image]
(Whitman, 1990) |
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Term
| What is one of the biggest advantages that Humans have with ecology? |
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Definition
We cook our food. This means we are able to get much more out of our food and can afford to feed for much less time in the day.
Originated in the Homo genus and is fundamental to our lives which we now require as well, uncooked food is inadequate
We also are aware of our mortality (other animlas may do this too) |
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Term
| Which human gender has a more variability in genetics? |
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Definition
Males are more variable genetically
Males have more extremes at higher and lower levels of the majority of traits |
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Term
| What is the grandmother effect? |
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Definition
This is the idea than in human nature, women who have alive grandmothers have a significantly higher LRS than women with dead grandmothers.
This is due to the idea of alloparental care for inclusive fitness amongst grandmothers who have gone through menopause and can no longer have children therefore they help to raise their daughters children.
Will take effect when the mother has stopped weaning the child |
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Term
What is the significance of this?
[image] |
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Definition
This is to do with the grandmother effect and the overlap of competition for resources between a young grandmother and an older mother if the mother is not directly related to the grandmother.
This is due to lower inclusive fitness for the grandmother and therefore more reluctance to aid the raising of the child
Small study done by (Lahdenperä et al, 2012) |
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Term
| How is the grandmother effect a factor in breast cancer genes? |
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Definition
The relative fitness of children born from carriers of the breast cancer genes have a 41% higher relative fitness than the others so why is it not strongly selected and the breast cancer gene spread throughout?
Because omen with breast cancer genes will stop reproducing much earlier |
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Term
| What are factors that will select for homosexuality? |
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Definition
-Mothers with homosexuals in the family will experience higher LRS
- Bisexuals will often be seen as ore attractive than heterosexuals and therefore will experience higher LRS
- Males with more have more older biological brothers will have a higher probability of being homosexual |
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Term
| What is the demographic transition? |
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Definition
This is the idea that in the past 150-200 years the size of families rapidly decreased. It is also linked in with the idea that the death rate has decreased and the total population has increased
Looks like this:
[image] |
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Term
| What is the menarche and why has it dropped in the West? |
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Definition
| The menarche is the age of first ovulation. It has dropped due to the fact that nutrition and health is much higher in this day and age. Kung women (traditional hunter gather tribe women) still have a relatively high menarche |
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Term
| What is difference between the primal hunter gatherer women and western women's fertility lifetime? |
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Definition
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Term
| What is the difference between Kung women and Western women in their fertility lifespan? |
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Definition
[image]
This is due to poorer nutrition and highly extended periods of lactation.
Lactation in Kung women will prevent cycling again until the lactation has stopped.
In western women, nutrition is so high that the natural contraception of lactation does not work |
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Term
What is the significance of this?
[image] |
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Definition
| This is the idea that it used to be the idea a of the lower social classes had less children and vice versa but now however this pattern has flipped |
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Term
| What did (Nettle, 2010) find out about neighbourhood quality, lifespan and the grandmother effect? |
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Definition
Found that in poorer quality neighbourhoods, the grandmother would become helpless much earlier due to degradation in healthy life and therefore less help can be given to the child's child. This leads to lower LRS (in theory)
Also found that effects in the females life will effect the time at which she will have children and that it can be fairly dictated by the idea of how long they are able to spend as a grandmother looking after their child's children and helping out |
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Term
| Does th idea of live fast die young apply to human ecological relationships |
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Definition
In a way yes, mainly only in men but the idea that the men who take many risks, live dangerous or violent lives tend to have higher RS but do not look after heir children and do not invest anything apart from their genetics.
They can also spread the genetic disorder which is an issue with the MAOA. This is linked to the 5% of men who will commit the 70% of all crime and violent crime
[image] |
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