Evolutionary Approach (L2)

Question 1

Assumptions of Natural Selection

Answer 1

1. Within a species there is variation among individuals.
2. Variation is heritable.
3. Organisms produce surplus offspring.
4. Competition occurs among individuals.
5. Reproductive success differs among individuals.

Question 2

What is the major problem with group selection + what is an explanation for self-sacrificing behavior?

Answer 2

Individuals may cheat; in nature, cheaters always prosper.

Kin selection (altruistic behavior is actually selfish).

Question 3

Levels of selection: species

Answer 3

Selective extinction of species. Removal of species within a group of species rather than genes within a species. This is thought to be a driving force in macroevolution.

Question 4

Which level of selection has the strongest evolutionary effect?

Answer 4

Selection acting on differences among individuals.

Question 5

Ultimate Factors

Answer 5

Long-term evolutionary causes of behavior.
Resource based: food, water, territory, mating, shelter, etc.
Answers the “WHY” questions about behavior.

Question 6

Proximate Factors

Answer 6

Immediate conditions or mechanisms that cause behavior.
Environmentally based: photoperiod, rainfall, olfaction.
Answers the “HOW” questions about behavior.

Question 7

What is an ethogram?

Answer 7

An inventory of the behaviors performed by a species of animal.

Question 8

Comparative method

Answer 8

Behaviors are compared between two or more species.
Species may be similar or different in the behavior.
Hypotheses may be tested to explain similarities or differences between species.

Question 9

Experimental method

Answer 9

One or more variables are controlled under natural or laboratory conditions.
If a natural experiment, individuals should be identified (usually by marking).