lecture 6 ecology

Question 1

behaviour – appropriate behaviour

Answer 1

those with more appropriate behaviour pass on MORE genes

Question 2

what does it mean ‘appropriate behaviour’

Answer 2

suited to biotic asnd abiotic enviornment (interactions, temp…) – more likely to survive and reproduce

Question 3

we explain behaviour in terms of what

Answer 3

affect on individual fitness – likelihood of animal passing genes.

Question 4

benefit of individual

Answer 4

if fitness is increased – more likely to survive and pass on genes

Question 5

costs of individual

Answer 5

if fitness is decreased – opposite, mire likely to die, have lower fitness, and puts individual at risk

Question 6

terms to remember

Answer 6

fitness, actor, recipient

Question 7

fitness defintion

Answer 7

refers to evolutionary fitness – how likely an individual is to pass on its genes

Question 8

actor definition

Answer 8

the animal performing the behaviour

Question 9

recipient definition

Answer 9

is/are other animals invovled

Question 10

1. altruism

Answer 10

behaviour where an individual helps at cost to theirselves to benefit survival and reproduction of other individuals / relatives.

Question 11

social behaviour costs vs benefits table

Answer 11

cooperative (both +)
Selfish (actor+ recipient -)
altruistic (actor - recipient +)
spiteful (both -)

Question 12

cooperative examples

Answer 12

packs (i.e wolves) – defense and hunting – they hunt in a pack, therefore cam bring down larger prey.
defense – individuals aggregate together in group therefore less picked on by predators

Question 13

selfish behaviour examples

Answer 13

actor = + recipient = -
territorality – individuals defends / preserves a territory not allowing other individuals to come in – benefit ffor actors as they get all of the resources, but not beneficial to the recipients who do not get those resources.

Question 14

spiteful

Answer 14

negatyive for both – surplus killing?

Question 15

altruistic – why does this non beneficial behaviour persist – give example

Answer 15

pikas – they live in rocky mountains/slopes
they live in small groups,
- have an alarm call they use to ward off predators
– the alarm is loud therefore it makes the pika calling it at a higher risk – allows predators to hone in on the alarm caller (actor) rather than the others in the group (individual)

Question 16

why is benefit not greater than cost in altruistic example

Answer 16

you havce to look at the inclusive fitness

Question 17

what is inclusive fitness

Answer 17

concept that there is more going on in terms of passing on genetic material than just in an individual and their direct offspring (relatives)

Question 18

what two things have affect on number of genes passed on (or affect on likelihood)

Answer 18

`1. producing offspring
2. Aid relatives to produce more offspring – you share some genes w relatives – therefore indirectly, if relative reproduces, some og your genes will be present,

Question 19

kin selection

Answer 19

framework we look at for inclusive fitness – selection for an act that enhances a relatives reproductive success.

Question 20

Hamiltons rules

Answer 20

natural selection (evolution) favours an act if C < r*B

Question 21

what does C represewnt

Answer 21

cost of altruist (actor) – lost reproduction

Question 22

what does r represent

Answer 22

relatedness (fraction of genes shared)

Question 23

what does B represent

Answer 23

benefit to recipient (increase reproduction)

Question 24

Scenario 1 – does it increase (evolutionary) fitness to save a sibling if you will die in the process

Answer 24

no, it will not increase inclusive fitness because C>r*B which does not follow Hamilton’s rule

Question 25

Scenario 2 -- does it increase (evolutionary) fitness to save a sibling if you MAY die in the process (risk)

Answer 25

risking dying does increase inclusive fitness -- depends on the cost because B and r do not change.

Question 26

Pikas behaviour, cost, benefits

Answer 26

Pikas -- altruistic behaviours are evolutionary benefical/fit the cost of the alarm is small -- yes it increases risk of being predated but it is not at 100%. the benefits is that they live in groups (family groups) so there is high relatedness, and more chance that their genes will be passed on

Question 27

reciprocal alturism

Answer 27

tit for tat -- return the favour -- why such stable social groups -- chimps grooming each other in hopes for favour rwturned in future

Question 28

group living and social organization -- when is it worth it to live in a group (benefits and costs)

Answer 28

benefits - cooperative feeding, defense of group costs - disease/parasite transmission because living in close proximity -- restricted reproduction

Question 29

why do animals stay in social groups

Answer 29

because benefits outweigh the costs

Question 30

restricted reproduction two types/examples

Answer 30

cooperative feeding, eusocial societies.

Question 31

cooperative feeding; restricted reproduction

Answer 31

individuals may delay their own reproduction to stick around and help raise other offs[ring (two examples are packs, and scrub jay)

Question 32

eusocial societies; restricted reproducton

Answer 32

division of animals into different castes (soldiers, workers, queen) [two examples are army ants and naked mole rats]

Question 33

cooperative feeding example in depth (packs)

Answer 33

dominance hierarchies -- some animals live in packs/groups -- some older and more mature (dominance) -- they limit the reproduction of other indiviuddals -- only the dominant individuals breed -- the helpers in the packs stay because of kin selection and inclusive fitness -- offspring survive better in packs individual fitness -- get stronger, more experience, and more likely to survive when they leave pack -- higher lifetime of reproduction

Question 34

cooperative feeding example (florida scrubjay) think of habitat, male, female, benefits,

Answer 34

live in patchy habitat (scrub oak) -- small family group -- they arebsurrounded by other habitats that are nottt substantial for the scrub jay -- breeding pair -- build nest, incubate eggs mature young stay on territory to feed yonger siblings, defend territory, and warn off predators juvenile males help more than females -- this is because scrub oak habitat is limited so often patches are already occupied therefore they have a small change of them finding teritory to call their own bUT -- when parent dies, juvenile male inherits family territory fully or divided amongst other males (partitioned) juvenile female never inherits family territory -- stick around to gain experience in child raising -- leads to longer lifetime of reproduction benefits -- kin selection individual fitness -- male only -- ingerit territory in future.

Question 35

Eusocial societies restricted reproduction examples (insects; army ants)

Answer 35

often seen in insects -- euoscoail insects --division of labour and behaviour into reproductive and nonreproductive castes army ants -- reproduction caste -- queen and severale males queen is only female that reproduces. non-reproductive castes -- all workers are sterile females -- defend, foraging, care of young. -- relatedness is slightly higher in sisters, instead of r=.5 it is r=.75 benefit - kin selection - sibling survival vewry high individual -- none but kin selection iss worth it `

Question 36

euosical societies example (mole rats )

Answer 36

live in harsh environments -- dry habitats colonies live in underground burrows workers are male and female -- they dig tunnels, gather food, and nest material for young soldiers -- many die to defend burrow (altruistic behaviour as they are putting themselves at risk) reproduction - 1 female (queen) and 1-3 males -- -- queen supresses reproduction in conlony (coercion) by behaviou (aggressive, attacks/kills any females attempting to reproduce) also by chemical cues -- hormone control why dont the rats leave -- because of harsh environment -- food is very limited -- they cannot survive in small groups or on own if leave fitness = 0 if stay fitness >0 be\ benefits = kin selection but no individual benefits

Question 37

what does environment influence

Answer 37

cost and benefits of group living

Question 38

group living evolves where

Answer 38

total fitness for staying in group > independent reproduction

Question 39

it pays to give up your delay in independent reproduction if

Answer 39

-- chance of independent reproduction is low -- survival is difficult (naked mole rate) -- opporunities for reproduction are few ( limited habitat -- scrub jay) -- a delat increases future reproduction potential (pack animals)

Question 40

Types of mating systems

Answer 40

monogamous, polygamous, promiscuous

Question 41

monogamous mating

Answer 41

single pair bond -- 2 individuals / parents - typically evolves where there is heavy parental investments (prairie vole)

Question 42

polygamous mating

Answer 42

two types -- polygynous (elks) and polyandrous (spotted sandpiper)

Question 43

polygynous

Answer 43

one male and multiple females -- male is bigger because they compete for female

Question 44

polyandrous

Answer 44

one female and multiple males -- female is bigger because they compete for males

Question 45

promiscuous ``

Answer 45

no strong mating bonds -- australian magpipe -- no parental sticking around

Question 46

polyandry in spotted sandpipers

Answer 46

females are first to arrive to breeding grounfs -- they are competing for males so they are bigger -- once theyve found male, they breed, lat eggs and leave -- they have time to reproduce wqith another male -- they let the male tale care of eggs and chicks

Question 47

whats the reason for the female spotted sandpipers leaving their nests

Answer 47

the environmental conditions -- there is enough food that only one p[arent is needed to raise the chicks -- females produce only a few eggs at a time so if they have the opportuity to mate again they take it to increase number of offspring. season is long enough for more than one clutch of eggs.