Lecture 2: Evolutionary approach

Question 1

5 assumptions of natural selection

Answer 1

1. Within a species there is variation among individuals.
2. Variations is heritable, natural selection operates on phenotype, and offspring resembles their parents.
3. organisms produce surplus offspring
4. competition occurs among individuals
5. reproductive success differs among individuals. Fruitful individuals are favored.

Question 2

4 levels of selection

Answer 2

gene
individual
group/ interdemic
species

Question 3

gene

Answer 3

selection favors a unit of gene, natural selection favors phenotype.

Question 4

group/ interdemic

Answer 4

selection favors group to avoid overpopulation, limit reproduction or commit suicide. (honey bees sting to protect group)

Question 5

Major problem with group selection

Answer 5

individuals may cheat, cheaters will prosper.

Question 6

Major problem with group selection

Answer 6

individuals may cheat, cheaters will prosper.

Question 7

What is self-sacrificing behavior?

Answer 7

kin selection

Question 8

altruistic

Answer 8

Behavior for the benefit of closely related kin . the behavior act decrease it’s own fitness but increase the fitness of closely related relatives.

Question 9

species

Answer 9

removes species within a group of species rather than genes within a species.

Question 10

which level of selection has the strongest evolutionary effect?

Answer 10

individual

selection acting on differences among individuals

Question 11

2 factors causing behavior

Answer 11

ultimate and proximate factors

Question 12

ultimate factors

Answer 12

longterm causes
resources –> food, water, territory
“why” questions

Question 13

proximate factors

Answer 13

immediate factors
photoperiod, rainfall, olfaction
“how” questions

Question 14

EX: Why do birds migrate?

Answer 14

ULTIMATE factors: not enough food at certain temperature, less competition for food.
PROXIMATE factors: increasing or decreasing photoperiod will trigger hormones.

Question 15

Methods of study

Answer 15

comparative and experimental method

Question 16

ethogram

Answer 16

an inventory of behaviors performed by a species of animal.

Question 17

ethogram

Answer 17

an inventory of behaviors performed by a species of animal.

Question 18

comparative method

Answer 18

• behaviors compared between 2 or more species

- hypothesis tested to compare similarities or differences between species.

Question 19

experimental method

Answer 19

one or more variables controlled under natural or lab conditions

Question 20

independent variable

Answer 20

factor to condition, treatment in experiment, blue gene around the glove

Question 21

dependent variable

Answer 21

observed or measured behavior, amount of venom injected.

Question 22

control group

Answer 22

unmanipulated set of subjects

Question 23

experimental group

Answer 23

manipulated set of test subjects

Question 24

null hypothesis

Answer 24

no differences, either accepted or rejected.

Question 25

6 Test hypothesis step

Answer 25

1. observe behavior
2. ask question about the behavior
3. form hypothesis and alternative hypothesis
4. generate testable predictions for each hypothesis.
5. test the hypothesis by matching the predictions with reality
6. hypothesis supported by data

Question 26

sexual competition hypothesis

Answer 26

infant delay estrus in female, male kill infant to reproduce sooner.

Question 27

sexual competition hypothesis

Answer 27

infant delay estrus in female, male kill infant to reproduce sooner.

Question 28

cannibalism hypothesis

Answer 28

due to pride killer male kills and consume

Question 29

social pathology hypothesis

Answer 29

lose contact, start killing, human interference

Question 30

aggression hypothesis

Answer 30

kill to defeat dominant male and overcome resistance

Question 31

certainty and science

Answer 31

no absolute certainty in conclusions, old ideas are replaced and modified.