BIOL 111 Lecture Notes - Population Ecology, Inclusive Fitness, Reciprocal Altruism

26 views2 pages

For unlimited access to Class Notes, a Class+ subscription is required.

29/11/11
Ecology:
1. Behavioural ecology: Study of animal behaviour in relation to the
environment
a. Ex Decide to eat? Factors like abundance, catchability, quality
determine this
b. Foraging theory: animals eating to maximize their energy intake,
though there are things that limit that intake
i. Fish/Daphnia: if there is low density of daphnia, fish will eat
anything, if there is high density fish will eat more of the big
ones
ii. Bears should eat fish fresh fish to maximize their energy intake
as new fish have more energy density than dead fish, but only
where catching the fish is easy
iii. Limitations: competition, predation risk, essential nutrients
c. Ex. Altruism? Animals referentially help their kin because doing so
increases the reproduction of alleles they both carry (“inclusive
fitness”)
i. Ex. Honey eater: only half reproduce, but other helps other in
the colony (closest relatives) to do so.
ii. Other possibilities:
1. group selection: even though you’re not related, it will
help the group as a whole
2. reciprocal altruism: if you help someone, they may help
ou back
3. punishment: one individual may be punished if altruism
is not demonstrated
4. gaining experience: helping a successful breeder may
help you succeed in the future
2. Population ecology: study of demographics in relation to the environment,
understanding population decline and recovery
a. Ex Why have cod not recovered after fishing ceased?
i. More seals means they’ll eat more cod
ii. Allee effects: pop of small density may have difficulty
reproducing, reducing of repro rate per individual
iii. Changes in life history traits: Cod after collapse causes small
cod which bear fewer eggs
iv. Cohort effect: big group of individuals at reproductive age make
lots of babies, but when they pass the reproductive stage there
aren’t enough individuals at reproductive age to maintain the
population
b. Population cycles: Populations of prey goes up so does the predator,
too many predators means all pretty dies, predators dies, prey goes
up, or too many prey means food depletion
3. Community ecology: study of interactions between species in relation to the
environment
Unlock document

This preview shows half of the first page of the document.
Unlock all 2 pages and 3 million more documents.

Already have an account? Log in

Get access

Grade+
$10 USD/m
Billed $120 USD annually
Homework Help
Class Notes
Textbook Notes
40 Verified Answers
Study Guides
1 Booster Class
Class+
$8 USD/m
Billed $96 USD annually
Homework Help
Class Notes
Textbook Notes
30 Verified Answers
Study Guides
1 Booster Class