Term
| Describe the small population paradigm. |
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Definition
| focuses on the population consequences of rareness and the abilities of small populations to deal with smallnenss as such |
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Term
| extinction vortex of small populations |
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Definition
| small populations fall into a vortex of positive feedback loops in which small population size leads to inbreeding and genetic drift, resulting in loss of genetic variability |
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Term
| What is the Minimum Viable Population (MVP)? |
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Definition
| population size that will ensure at some acceptable level of risk that the population will persist for a specified time. |
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Term
| Three types of variation that lead to population loss? |
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Definition
1. Demographic Stochasity - random differences in birth and death rates. If only a few individuals make up a population the loss of a few could be detrimental to overall pop. If a female produces only male offspring, pop could disappear.
2. Genetic Stochasticity - decrease in heterozygosity leads to inbreeding.
3. Environmental/Natural Stochasticity - changes in weather and catastrophic events (fire, flood, hurricanes)
2. |
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Term
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Definition
| Rule proposed by Franklin, saying that 50 animals/plants are needed to prevent inbreeding suppression and 500 animals/plants were needed to prevent genetic drift. This is rule of thumb b/c it considers 1 animal in effective population size. |
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Term
| What is effective population size? |
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Definition
| the size of an ideal population that would undergo the same amount of genetic drift as the population under consideration. the number of individuals in a population that contribute genes to the next generation. |
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Term
| Two types of MVP models, thier parameters, and limitations |
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Definition
1. Demographic Extinction - depends on intrinsic rate of natural increas (r) and varians. Calculates average persistance time of a population of a given size with specific demographic characteristics (b,d,age structure). This model gives an average persistance time for a large number of hypothetical populations. for any one population, actual persistance time may be far greater or shorter.
2. Genetic Model for Extinction - calculates minimum population size necessary to avoid loss of heteroztgosity due to inbreeding and genetic drift |
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Term
| What is Population Viability Anaylsis (PVA)? |
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Definition
| analysis using MVP models on specific species or populations and proposing a management plan |
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Term
| Evil quartet of deterministic extinction? |
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Definition
1. Habitat Destruction and fragmentation
2. Overkill - hunting or fishing rate that exceeds populations ability to rebound
3. Introduced species
4. Chains of extinction |
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Term
| two paradigms or conservation biology? |
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Definition
1. Small population paradigm
2. Declining population paradigm |
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Term
| Describe the declining population paradigm? |
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Definition
| focuses on the ways of detecting, diagnosing, and halting population decline. This approach is action oriented and is viewed in demographic terms. |
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Term
| Difference b/w deterministic and nondeterministic extinctions? |
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Definition
| Deterministic occur when some essential resource is removed or when something lethal is introduced into the environment. Non deterministic extinction are the stochastic extinctions that are the random variations in nature. |
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Term
| Advantages and Disadvantages of Conservation Corridors? |
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Definition
Ads: Immigration, Emmigration (migration). Decrease inbreeding suppresion. Rivers could prevent fire rom destroying everything. Mix of habitats.
Disads: spread of disease, outbreeding suppression, contagious catastrophe, Exposure of wildlife to hunters, high cost |
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Term
| What is the SLOSS Debate? |
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Definition
| Single Layer or Several Small Reserves argument. Argued between ads/cons in large conservation areas vs. several small conservation areas. Large cons. areas protect against catastrophic events whereas several small provide diverse habitat and more possible protected species. Solution was creation of corridors however, state of world is so bad that people just want to save annything that is left. |
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Term
| Three types of indicator species? |
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Definition
1. Umbrella species - require large area, if you protect this area you essentially protect other species
2. Flagship species - popular species that serve as conservation symbols
3. Keystone Species - pivotal species that maintain community structure |
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Term
| Rivet model of community? and founder? |
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Definition
1. Paul and Anne Ehrlich
2. each species in the ecosystem represents a rivet. Everytime you take out a rivet you weaken the overall function of the system. This is the conservation approach to protect species. Every species counts. |
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Term
| Passenger (Redundancy) Model? |
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Definition
1.Walker
2. throw a passenger out of the plane without harming the overall integrity of the whole system. The species are unnecessary to the overall system. Better not throw out the keystone species. This is the more liberal approach. example is loss of chestnut without major loss of other species. |
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Term
| Three types of ecological boundaries? |
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Definition
1. Sharp - short ecotone (transition zone) sometimes env. factors play role such as fire are altitude
2. Transition - large ecotone such as brackish water
3. mosaic - spread out in patches then changes over into 1 major type like in salt marshes |
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Term
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Definition
| ecotone is the transition b/w two adjacent ecosystems whereas, tension zone is an area where species with unique ecosystems overlap. |
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Term
| who developed interactive ( fundamental) school of thought and what did it entail? |
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Definition
| Clemens, Tansley, and lenoble beleived that species were locked into association by mandatory biotic interactions (coevolution and interdependence) |
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Term
| Predictions of fundamental school of thought? 3 |
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Definition
1. Species more likely to appear in groups and dissappear in groups
2. Closed Community
3. Sharp boundaries b/w communities (soil type, fire frequency, animal dist.) |
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Term
| Predictions of Individualistic school of thought? 3 |
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Definition
1. Come in and drop out unrelated to other species
2. Open Communities
3. Diffuse boundaries b/w communities |
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Term
| Who developed individualistic school of thought and what did it entail? |
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Definition
| Gleason and Whitaker - communities are haphazardly assembled of populations adapted to particular physical and chemcial conditions. |
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Term
| what is the difference b/w facilitation and enablement? |
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Definition
| Facillitation is where a species alters and environment to inhibit their existance whereas, enablement is where they make it better for themselves. |
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Term
| Difference b/w primary and secondary succession? |
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Definition
| Primary succession starts with a sterile environment; wheras, secondary usually has soil w/ seebank, fungi, or propagules. |
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Term
| diagram of ecological succession? |
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Definition
| pioneer community, stage 2, stage 3...climax community(the only one that replaces itself) |
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Term
| monoclimax, polyclimax, climax pattern, and disclimax |
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Definition
| Monoclimax is completely determined by climate, polyclimax influenced by soil and animals, climax pattern is as you move along gradient climax shifts, and disclimax is whens something is interfereing with ecosystem to disallow true climax. |
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Term
| What are the three models of succession? |
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Definition
1. Facillitation
2. Inhibition
3. Tolerance |
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Term
| Traits of pioneer vs. climax species |
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Definition
pioneer species are r-selected, reproduce quickly, and live shortly
climax species are k selected, live longer, reproduce slower |
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Term
| What is the facilitation model of succession? |
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Definition
| where pioneer species change the env. to hinder their own existance and help others establish |
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Term
| What is the inhibition model of succession? 5 traits |
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Definition
1. no species is a superior competitor
2. which ever species arrives first holds strong
3. Early settlers modify env. to help themselves
4. Not an orderly process
5. Eventually leads to climax |
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Term
| Describe the tolerance model of succession? 4 traits |
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Definition
1. any species can start succession (no pioneers)
2. Over time, the species most tolerant to limiting resources gains prominance
3. No predictable stages
4. Early occupants make the env. less suitable for others |
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Term
| Draw nobels diagrams containing: |
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Definition
| primary, secondary, inhibition, tolerance, random colonization |
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Term
| what is the equilibrium hypothesis? |
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Definition
| inter/intraspecific species interactions act to stabilize the community. |
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Term
| What are three equilibrium hypothesis? |
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Definition
1. Niche Diversification
2. Circular Networks
3. Compensatory Mortality |
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Term
| what is the niche diversification hypothesis? example? |
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Definition
| over ecolutionary time, interspecific competition results in specialization (narrower niched breadths) which allows more species to occupy a resource gradient. Example is # of insects that occupy canopy of single tropical tree |
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Term
| What is the circular network hypothesis? exampple? |
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Definition
| competition is intransitive and non-hierarchical which means species a can outcompete species b, species b outcometes species c, but species c can outcompete species A. Example is the sponge and invertebrate communities on sunken ships. |
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Term
| What is the compensatory mortality hypothesis? |
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Definition
| mortality unrelated to competition occurs mainly on the superior competitor. For example, the sea star, a keystone species, prefers to prey on mussels which would outcompete all other algae and invertebrates if not held in check by the sea star. |
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Term
| what is the non-equilibrium hypothesis? |
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Definition
| local communities are not stable although global communities may be. |
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Term
| what are three non-equilibrium hypotheses? |
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Definition
1. intermediate disturbance
2. lottery hypothesis
3. gradual change hypo. |
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Term
| What is the intermediate change hypothesis? |
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Definition
| non-eq. where frequent disturbance interrupts competitive exlusion and prevents dominant competitors from excluding less competitive species. An example is the diversity of forests in areas where hurricanes are frequent |
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Term
| what is the lottery hypothesis? |
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Definition
| non-eq hyp. where a place in the community is secured through a lottery in which each species has an equal chance of joining by settling out of the plankton at an opportune time. Depends on high variability in larval pool. local, recruitment being independent of local reproduction, and death rates being unaffected by competition. tropical reef fish communities may provide an example |
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Term
| what is the gradual change hypothesis? |
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Definition
| non-eq hyp. when the environment changes gradually over time in such a way that the ranking of competitive ability is reversed prior to copetitve exclusion. one example is the diversity of phytoplankton collected from a lakde during the spring. |
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