Lec 11- behavior and fitness

Question 1

ethology

Answer 1

study of behavior

Question 2

behavioral ecology

Answer 2

study of behavior in ecological context
- focuses on vertebrate and invertebrate
- expanded to plants and microbes

Question 3

what is behavior?

Answer 3

• difficult to define
• lack consensus on whether “motion” is prerequisite
• should it apply to plants and microbes

internally coordinated responses (actions or inactions) of whole living organisms (individual or groups) to internal and/or external stimuli
- any response

Question 4

Hamilton’s 4 classes of social interaction

Answer 4

• based on fitness consequences
  cooperation, altruism, selfishness, spite

Question 5

cooperation

Answer 5

both donor and recipient benefit
- within species and often b/w related animals
- exchange resources and protection

Question 6

altruism

Answer 6

recipient benefits, donor doesnt

Question 7

selfishness

Answer 7

donor benefits and recipient doesn’t

Question 8

spite

Answer 8

donor and recipient don’t benefit

Question 9

fitness

Answer 9

of offspring contributed by individual relative
- no of offspring produced by other members of pop

Question 10

donor

Answer 10

indivdual performing action

Question 11

recipient

Answer 11

individual recognizing behavior

Question 12

inclusive fitness

Answer 12

determined by survival and repro + the survival and repro of relatives
- behavioral interactions b/w 2 individuals may have +/- effects on either individuals inclusive fitness
- affects closest relatives and interpret social interactions like altruism

Question 13

how does natural selection favor behavior?

Answer 13

increases inclusive fitness of individuals
- individuals selected for or against causing evolution within a population
- actions are on individuals but affects future generations

Question 14

how does natural selection work on behavior?

Answer 14

only occur if behavior has a genetic base

Question 15

honeybees and behavior

Answer 15

work is distributed based on age
- young stay in to care for young bees
- older go out to collect food
- work behavior tied to levels of specific protein kinase (PKG) produced by one gene
- more PKG = work out
- less PKG = work in
with age comes changes in work behavior

Question 16

adaptive behavior

Answer 16

• acquired
• increases the fitness of organisms and will be selected for over multiple gen
• relevant to evolution
• range of options

expression (phenotype) depends on genes and environmental conditions

Question 17

which 2 behaviors should be selected for by natural selection?

Answer 17

cooperation and selfishness
- increase donor fitness

Question 18

which 2 behaviors should be selected against by natural selection?

Answer 18

altruism and spite
- decrease donor fitness

Question 19

altruism

Answer 19

b/w relatives
- direct observations and molecular data
- red squirrel
- donor loses energy to care for recipient (distant relatives)
- recipient can pass on genes

Question 20

why would donor commit to altruism?

Answer 20

1. group selection
2. manipulation
3. reciprocal altruism
4. kin selection

Question 21

group selection

Answer 21

individuals neglect own needs in favor of group
- part of own population and genes are in relatives

Question 22

manipulation

Answer 22

donor does not recognize it is being parasitized
- tricked so does not know they arent related

Question 23

reciprocal altruism

Answer 23

recipient will pay back at one point in future

Question 24

kin selection

Answer 24

individuals increase inclusive fitness by helping survival and repro of relatives (kin)
- able to spread genes for future generations

Question 25

coefficient of relatedness (CR)

Answer 25

probability that an allele at given locus will be identical by descent among 2 individuals in population - quantify relatedness -

Question 26

CR among kin

Answer 26

50% reduction in coefficient of relationship b/w each additional connection - small = distant relatedness - big = closer in relatedness parent - self : 50% (direct) grandparent - child: 25% (skip 1 gen)

Question 27

altruism and kin selection

Answer 27

cost/benefit < CR

Question 28

how does the cost get outweighed?

Answer 28

the more distant relationship, the smaller the CR, the larger the benefits

Question 29

how does the benefits get outweighed?

Answer 29

the higher the CR, the more likely the donor will benefit from being altruistic

Question 30

cowbird- selfishness

Answer 30

laying eggs in other nests - obligate brood parasite - parents dont waste energy to take care of eggs and others will care for genes to get passed on

Question 31

phoebe and cowbird eggs

Answer 31

cowbird lay eggs in phoebe bc they look the same size and shape but diff colors

Question 32

phoebe pov of cowbird eggs

Answer 32

raising eggs is altruistic behavior - manipulation: donor has no means to recognize/prevent interactions - doesnt know its being tricked

Question 33

European badger

Answer 33

spite - tuberculosis infected so leave area to infect others bc they have a fitness disadvantage - spread to non-kin so they have fitness disadvantage

Question 34

sociality

Answer 34

group of individuals living together and involves some degree of cooperation between individuals - cooperative feeding (capture and eat together) - defense of social group (diff roles w/in group) - restricted repro opportunities (dominant M and F and no others can mate)

Question 35

examples of social behavior

Answer 35

- mutual grooming (monkeys) - group protection of young (young in and old out) - highly complex societies (colonies)

Question 36

cooperative breeders

Answer 36

live in groups (pack) adults help with offspring - defense - prepare/maintain living area - feed young

Question 37

why does cooperative breeding work?

Answer 37

members most likely relatives - inclusive fitness (increase fitness of close relatives) tit for tat - help the group then they will help you (reciprocal altruism)

Question 38

eusociality

Answer 38

highly complex social behavior

Question 39

eusocial animals

Answer 39

- individuals of more than one gen live together (multigenerational community) - cooperative care of young - division of individuals into sterile/non-reproductive and reproductive castes (excludes cooperative breeding animals except mole rat) insects, crustaceans and mole rat

Question 40

leaf cutter ants

Answer 40

eusocial - one most socially complex organisms - up to 7 casts - workers have diff looks

Question 41

naked mole rat

Answer 41

one of 2 eusocial mammals (Damarland mole-rat, south africa) - 3 casts

Question 42

comparing leafcutter and mole rat

Answer 42

queen - only reproductive person with M (interbreeding common as only have 1 Queen) small - foraging and maintenance (convergent evolution) large - defense

Question 43

why has eusociality evolved?

Answer 43

kin selection- role as individuals in colonies have high degree of relatedness ecological constraints- role in defense and maintenance of burrow sys