order

energy processing

response to enviornment

regulation

reproduction

growth and developement

evolutionary adapatation

1. Bacteria: no nucleus

2. Archae: no nucleus

3. Eukartyoes : have nuclear cell: protists, animals, fungi, plants (kingdoms)

eukaryotic

multi cellular

heterotrophic, ingest own food

lack cell wall

bodies made up of cells-organized into tissues

specific dev. patters/genes

Hertiable change in a population across geneartions

~ small scale changes with a lineage "microevolution"

ex: bird wirth short tail eventually gets longer tail

~large scale-formation of new species "Macro evolution"

example: changes that create new species

to combat disease

to create new crops

to understand the diversity of life

to protect that diversity

species arent permanent == they change overtime

Darwin (1809-1882) was a naturalist on a round the world sea voyage- HMS Beagles 1831-1836

Darwin's observations:

in nature differerence between species and variations of species sometimes unclear

gradients of change in species

1838 Darwin read T Malthus essay "On Population" additional insight:

~breeders consciously select desirable characteristids

~develop breeds more different from each other than wild

1844: unpublished essay on natural selection

1856: Began huge book on natural selection

travels in SE Asia

Darwin and Wallace publish their theories together

~descent with modification: species today descend from ancesteral

~natural selection

1. Variation- individuals within a species vary

2. Inheritance: traits will be passed from parent to offspring

3. Overproduction: natural pop more individuals than the enviornment can support

4. mortality: more individuals born than survive

5. Differential reporduction: ones with favored traits will leave more offspring

change in a lineage over time

generation to generation change in allele frequency in a population

e.g. population with 80% G alleles ~ 50% G alleles

changes in a gene pool-sum of all alleles in a population

We see changes in traits- phenotypes and natural selection acts on

evolutionary change requires change in genotype

combination of:

genetic drift-accident/chance

gene flow- migration/movement of gene flows one pop to another

mutation - changes in DNA

-natural selection

effects of random change on population (important in small pop)

~ can greatly reduce or even eliminate alleles

(ex: all chickaddes sitting in a tree die)

• bottleneck effect: pop decreates (lots of alleles lost); pop size increases, genetic diveristy still low

ex: cheetahs two bottlenecks

• Founder effect: individuals isolated from main pop. Make new population

~loss of allele (variety)

~increase in allels that were rare in original pop

movement of genes from one population to another

~increase genetic diversity within a pop

~ reduces differences between populations

heritable change in Dna/random

~ rare, not a big change in allele frequency in one geneartion

mutatoins are usually bad, but not always

mutation

gene flow

sexual reproduction- new combaintation of alleles

Seletction is not all or nothing: it is a pop. level process

Directional Selection

Stabalizing selection

Disruptive selection

All of these forms of selection can use evolutionary change

favors individuals at one extreme of a phenotype distrubution

changes the avg (mean) value of a trait

favors individuals with intermediate phenotypes (no change on mean-but less variation)

can act on traits uesd in mate identificaiton/redues variation

ex: gestation period in mammals

extreme phenotypes are favored

-increase variation in species (no change in mean)

Microevolution and Speciation

Biological species concept

speciation can occur through the processes that cause microevolution

the biological species concept: group of pop that can exchange genes (actually, potentially) and produce fertile offspring and are reproductively isolated from other groups

as long as two forms do interbreed they cannot diverge into distinct species

allopatric (different geographic areas)

sympatric (some geographic area)

parapatric (contagious areas, no specifric extinsic barrier)

1. single pop, homogenous (one) env.

2. differentiation of env. and migration

3. further differentiation and migration leading to a greographic isolation of some races and subspecies

4. ongoing differentation, reproductive isolation mechanisms evolve

5. formerly isolated pop coexists (env. change) now remain distinct

reproductive isolation may occur when pop becomes geographically isolated

differnt habitats: selection makes them different (microevolution)

genetic drift - change, unpredictable, fluctuations in allele frequency

most effective in small pop (slow process, probably not onlyprocess)

bottle neck effect

early part of divergence process not that different creates hybrids

can cause loff of species

Possible outcomes of hybridizatoin

1. fusion

2. continue hybridization, stable zone or moving zone

3. Reinforcement : selection for increased differences (in mating character) in sympatry hybridization

common in plants/rare in animals

fossil record rich wi/transitional forms

Evol of cats (case of macro evolution)

to determine 37 existing cat species

-molecular homology: compound sequence of 30 genes

to determine when speciation occursed:

fossil record

molecular clock: based on extent of diff. btwen diff. genes, can estimate how long ago speciation occured

evolution of new lineages

Rate of speciation

in lab: 20 generations (fruit flies)

in the wild? 12, 300 year == 500 species Lake Victoria

why/how sudden rabid and abundant specition in ciclids? -natural selection, sexual selection

ex: horses small-- Large

browsers -- grazers

males and females often differ in color etc.

usually in males who are brightly colored

struggle between individual of one sex for another sex

help organisms maintain mates, but are of little value or costly in day to day survival

1. Mate choice (usually female choice) power to charm females

2. Intrasexual selection: usually male/male competition

strategies employed by each sex to ensure reproductive sucess

females: choosey, discriminating

males: aggressive, competetive, flashy, less discriminatory

why the assymetry

(mating/care)

differences evolves because of differnces in repdocutive biology

1. relative investment in reproduction: usually greater for females therefore females are more choosy

2. reproductive potential: usually greater for males, therefore males more aggressive, mean, competetive

The greater the desparity among males in terms of number of mates, the greater the level of aggression

variation in reproductive sucess is greater for males than females

"Good genes' sexual selection: females select males whse ornaments indicate they have "good genes"

Sexual selectoin causes evolutionary change

in males traits used to attract females or compete with other males

in females prefrence for those traits

often this help is costly

dangeous-increase risk of predation

extra work -decreate number of own offspring

when the helper pays a cost, the behavior is altruistic

helping kin (among relatives): because helping kin increases your own fitness indirectly

relatives share genes-increases own fitness

more copies of its genes in the next generation

the number of offspring an individual has of its own and because of helping kin this is called 'kin selection'

many kinds of cooperative behavior evolve through kin selection

natural selection

sexual selection

kin selection

vary within a pop

be genetically based

affect suvival/production

alternative mating strategies

in some species males use strategies to obtain mates

spong isopeds have 3 alternative mating strategies

`alpha: defends

beta: mimics

gamma: sneaks copulations

each males behavioral mating type based on gentics

traits can incecrease/decrease mating but decrease/increase survival

Parental care is costly

-increased energy costs (feeding young, keeping them warm)

increased predation: risk for the parent

reduced mating opportunities

Why provide parental care?

increases survival of offspring and this increases parents fitness

no care

female only

male only

bi-parental

sibling care

Mammals: female only

Fish: male only

birds: bi-parental

Fish male: don't give up mating opportunities because females come to them

primarily natural selection that determines parent care, but also sexual

communication mediates many interactions

-btwn parents and offspring

btwn potential mates

btwn social partners

btwn competitors

Communication includes producing a signal, then recieving and reacting to that signal

Communication honesty

Signals can be manipulative

exploit response to increase own fitness

spatial cue (not communication)-mother returns to same location

visual: offspring look different (color, shape, size)

olfactory: parents learn smell of own infant

acoustic: offspring/parents give distinctive call

signals that indicate species identity should

~ differ btwn species

~ be consistent w/in species

Can be visual, acoustic, olfactory etc

simple and complex behavior can be innate or learned

the capacity to learn has a genetic basis

learned behavior can be transmitted to subsequent generations-which can result in cultural evolution

early experience during sensitive period determines choices better in life

~habitual: recognize 'home'

ex: salmon recognize odor cues of home river to return for spawning

~filial: recognize social patterns / imprint on siblings and prefer to associate with similar phenotypes

~sexual: recognize species and mates/ imprint on parent and prefer mates with similar phenotypes

habituation-reduced response to repeated stimulus

neighbor-strange recognition in song birds

benefit: reduce costly response

bees associate flower color w/nectar reward

benefit: productive, allows increased responsiveness to env.

behaviors that are socially transmitted within and between generations

Culture can affect genetic evolution -changes selection

Cultural evolution can be very rapid

-biological evolution limited by generation time

-cultural evolution is not

study of the distribution of organisms and abundance and interactions btwn organisms and their enviornment

population = a group of individuals of the same species that live in the same area

rely on the same resources

are influenced by same env. factors

likely to interact and interbreed with each other

1. Pop characteristics:

density

dispersion

pop structure

pop rates

2. Life history traits

limited by:

~resources -food, water, nest sites, quality

limiting agents: disease, parasites, predators

1. clumped dispersion: individual aggregated in patches

often results from...

~uneven distruction of resources

~mating or other social behavior

2. Uniform dispersion (individuals evenly spread)

A. Aggression interactions

2. Severe competition for resources

3. Random dispersion

no pattern seen

"null model" -expected if no special forces acting on spatial distribution

sex ratio: # males: # females

primary: conception

secondary: birth/hatching

ex: human males 106: 100 females

tertiary: later stage in life

ex: senior females: 1 male: 2 females

1. reproduction- related stress

2. dispersal (leaving the nest)-increased risk of pop in sex disparity

3. Intraspecific competition

~ dominance status

~energetic requirements

plot porportion of individuals alive at each age

type 1: early high survivial in life, later on drop off (humans)

type 2: high mortality in beginning, then high survival ship (oysters)

type 3: constant death rate (rodents)

traits that affect organisims schedule or reproduction and survival

r-strategists: live fast, die young: many babies

k-strategists: slow and steady

                         R                       K

Offspring                  many                   few

offspring size            small                   large

parental care             none                  lots

growth                      fast                   slow

reproductive age        young               delayed

                                type 3              type 1

density not important

abiotic factor/flood, tornado, humidity, soil, pH

affect on pop size == unpredictable

Density dependent and density independent controls often interrelated

social animals can resist weather conditions by collective behavior

What happen when limits set in?

pop sizes can crash - but pop can stabalize

logistic growth model-idealized po growth that is slowed by pop limitation factors as pop size increased (dont need to know equation)

how big a pop enviornment can support

pop growth rate small when pop small

as it gets larger growth larger - before slowing down (carrying capacity)

many k-selected species

study of interactions w/species w/ other species

all pops of organisims living close enough together for potential interaction

possible interspecific interaction

~predation

~symbiosis -favorable

~competition

+/- interaction, eating, not being eaten neccessary for reproductive success

Forms of predation

-herbivory: herbivores eat plant

-carnivory- carnivores eat animals

paresitism: parasites consume small amts of tissue from host

interaction btwn 2 organisms (or more) different species that involves direct physical contact

+/+ mutualism

endosymbiosim-one organisms lives inside another

not very common

+/0

+/-

parasite live in/on host

~smaller

~reproduce faster

~adapted to specific host

~dont want to kill host

-/-

can occur when resources are scarce, not enough to go around

~ cause of desnity-dependent factors

how an organisms makes a living

set of habitat requirements and role species playing in the ecosystem

interspecific competition can occur when niche overlaps

resource it actually uses

usually smaller than the fundamental niche due to competition

-localized extinction

-coexist

Dominant species: speciies in a community that are most abundant or have the highest biomass (total mass of all individuals in pop)

Keystone species: species that has a disproportionate effect on its env. relative to its abundance

species that cause physical change in enviornment

Exotic/invasive species can outcome native species

-biosphere

-ecosystem

-community

-pop

-organism

-organ system

-organ

-tissue

-cell organelle

-molecules (water, macromolecules)

-atoms

O-H

^H

O=oxygen, H= hydrogen

atoms sharing a pair of electrons (e-)

O is more electronegative (attracts electrons) more than H

-electrons spend more time around O more than H

O partial negative charge (O -)

Hydrogen partial pos charge (H +)

Polar covalent bond = water is a polar molecule

others: NH

SH

       varieties of species were sometimes unclear

2)   Fossil animals are now extinct but similar to living species

3)   Geographic variation and species replacement

4)   Gradients of change in species among islands, but also within islands

All led to conclusion that

exponential: r-strategists, fast

logistic: k-strategists, slower

exponential: Rate of population expansion under ideal condition

G=rN

G=Growth rate

N= # of individuals at particular time

r= rate of increase

r = birth rate – death rate

r is small if...

• individuals not fecund or fertile
• sex ratio skewed towards females
• long generation time
  

Idealized population

growth that is slow

ed by population limiting

factors as population size

increases –GROWTH

WITH CONSTRAINT

covalent bond - atoms sharing a pair of electrons

O is more electronegative than H (attracts electrons)

electrons spend more time around O than H

water, NH, and SH have polar covlaent bonds

polar molecules dissolve in water

attraction of partial charges

water can h-bond to other polar molecules (NH3== Ammonia)

Ions (charged particles) dissolve in water

(Organic macromolecules) carbon-containing large molecules

Carbohydrates

Lipids

Proteins

nucleic acids

monomer + monomer = dimer (big molecule made of small subunit molecules)

How connect monomers? Dehydration synthesis : monomer in, water out

Hydrolysis: breaking apart monomers, water in/monomer out

(sugars)

monomer = monosaccharide (glucose)

mono = single saccharide sugar

Disaccharides:

broken down for quick energy (lactose breaks lactose disaccharide down)

Oligosaccharide

3-20 monosaccharides

Carbohydrates are identification badges for cell

Polysacchardie

many monosaccharides (cellulose, starch, glycogen)

Functions: energy storage (plants: starch; people: glycogen)

Structure: cellulose: cell wall in plants; chitin in insects (exoskeleton)

Amino Acids and R group

monomer = amino acid (recognize structure) central carbon w/ amino acid group

R group= rest of molecule (variable) = 20 different amino acids; properties of R group dictate how they interact

-w/ each other

w/their enviornment

Some are changed - look for +/- == charged

hydrophilic (water loving): OH, NH, SH in group

hydrophobic (water fearing) -C-H bonds NOT polar

Dipeptide and polypeptides

H-0-0-OH

polypeptide: amino acid + amino acid + amino acid...etc

man, varied functions

Levels of polypeptide/protein structure

1. Primary Structure- linear sequence of amino acids

2. Secondary Structure: localized folding

alpha helix: fold into spiral shape

beta pleated sheet: folds aroudn to put pieces nearer to eahch other (accordian)

3. Tertiary structure: most fold into globular shape, final 3D shape

4. some proteins are composed of two or more distinct polypeptides

5. Sickle cell anemia: folds wrong, can't carry as much oxygen

Enzymes

catalyst that speed up reaction without being consumed

Optimal conditions : temperature and pH

fat!

Functions: