Behavior Ecology

Question 1

What are two levels of causation?

Answer 1

1. Proximate
2. Ultimate

Question 2

What questions do proximate questions answer? Give an example.

Answer 2

It answers the how.
Ex. How does the behavior occur in terms of the hormonal, neurological, or skeletal-muscular mechanisms?

Question 3

What questions do ultimate questions answer? Give an example.

Answer 3

It answers the why.
Ex. Why is this behavior observed in terms of historic or evolutionary forces?

Question 4

Who was Nikolaas Tinbergen?

Answer 4

One of the founders of modern ethology (the study of animal behavior).

Question 5

What were the four ethology questions that Nicolaas Tinbergen asked?

Answer 5

1. Causation (Mechanism)
2. Development (Ontogeny)
3. Evolution (Phylogeny)
4. Function (Adaptive Value)

Question 6

What does causation (mechanism) ask?

Answer 6

What internal or external stimuli trigger the behavior?

Question 7

What does development (ontogeny) ask?

Answer 7

How does the behavior develop during an individual’s lifetime?

Question 8

What does evolution (phylogeny) ask?

Answer 8

How did this behavior evolve over the species’ history?

Question 9

What does function (adaptive value) ask?

Answer 9

How does the behavior
contribute to the organism’s survival and reproduction?

Question 10

Which of the four question are proximate versus ultimate questions?

Answer 10

Proximate
1. Causation (mechanism)
2. Development (Ontogeny)
Ultimate
1. Evolution (phylogeny)
2. Function (adaptive value)

Question 11

What are two types of behaviors?

Answer 11

1. Fixed action patterns
2. Condition-dependent

Question 12

What are fixed action patters?

Answer 12

1. These are innate (born-with) behaviors.
2. They are stereotyped, performed the same way every time.

Question 13

What are condition-dependent behaviors?

Answer 13

1. Behaviors that change due to learning or environmental conditions.
2. Flexible responses; “decision making”

Question 14

What is imprinting behavior?

Answer 14

A strong, rapid attachment is formed with the first moving object they encounter after birth.

Question 15

What are two types of imprinting behavior?

Answer 15

1. Sexual imprinting
2. Rival imprinting

Question 16

What is sexual imprinting?

Answer 16

Females use their mother’s color as a template to choosing a mate.

Question 17

What is rival imprinting?

Answer 17

Males develop aggression biases
that are triggered by the coloration of rivals that
are the same color as their mother.

Question 18

Why do ecologists use the cost-benefit analysis?

Answer 18

The cost–benefit
analysis to understand and quantify the behavioral choices that animals make.

Question 19

What is fitness?

Answer 19

The number of offspring produced by an individual in its lifetime.

Question 20

True or false: Organisms have a mix of both fixed action patterns and condition-dependent behaviors?

Answer 20

True

Question 21

What is Optimal Foraging Theory?

Answer 21

Optimal Foraging Theory explains how animals make decisions to maximize their fitness by maximizing feeding efficiency.

Question 22

How does feeding efficiency relate to fitness?

Answer 22

Fitness ∝ Feeding efficiency: Animals that gather food more efficiently survive better and reproduce more, passing on the behavior genetically.

Question 23

Do animals achieve perfect optimal behavior?

Answer 23

Rarely. Biological systems are variable, and animals face real-world trade-offs, so behaviors are often good enough rather than mathematically optimal.

Question 24

Do all species optimize the same variables when foraging?

Answer 24

No. Different species face different challenges.

Question 25

What is natural selection (broad sense)?

Answer 25

Change in allele frequency due to dis/advantage in relative fitness.

Question 26

What is natural selection (narrow sense)?

Answer 26

Change in allele frequency due to dis/advantage in competition for survival or fecundity.

Question 27

What is sexual selection?

Answer 27

Change in allele frequency due to dis/advantage in competition for access to gametes (mates).

Question 28

What is kin selection?

Answer 28

Change in allele frequency due to dis/advantage of alleles expressed in closely related individuals.

Question 29

What is sexual dimorphism?

Answer 29

Sexual dimorphism means males and females of the same species look or behave differently.

Question 30

What are five traits of sexual dimorphism?

Answer 30

1. Traits often elaborate, exaggerated (size, tail length, song...) 2. Often seen only in mature individuals 3. Often seen only in breeding season 4. Often seen only in males 5. Often seemingly disadvantageous

Question 31

What causes asymmetries in the cost of reproduction?

Answer 31

1. Females usually invest more energy in reproduction than males. 2. Eggs > sperm in cost and size 3. Parental care is often greater in females. This makes reproduction more expensive for females.

Question 32

How do reproductive cost asymmetries influence sexual selection?

Answer 32

The sex with the lower reproductive cost (usually males) benefits more from additional mating opportunities. This leads to greater intensity of selection on males to evolve traits that improve mating success.

Question 33

What are secondary sexual traits?

Answer 33

Exaggerated, sexually dimorphic traits evolved to increase mating success under sexual selection.

Question 34

Why do males typically have more exaggerated sexual traits?

Answer 34

Because males often gain more reproductive benefits from additional matings, selection strongly favors traits that help them compete or attract mates.

Question 35

What are two types of selection of secondary sexual traits?

Answer 35

1. Intra-sexual selection 2. Inter-sexual selection

Question 36

What is intra-sexual selection?

Answer 36

Competition among members of the same sex to secure mates.

Question 37

What is Inter-sexual selection?

Answer 37

Choosiness in one sex for particular traits in the competing sex.

Question 38

What are the two parts of intrasexual selection?

Answer 38

1. Combat- Intrasexual selection, usually “male-male competition" 2. Scramble- usually "male-male competition", competitive searching for mates.

Question 39

What are the three parts of intersexual selection?

Answer 39

1. Indicator mechanisms 2. Resource-based mechanisms 3. Pre-existing sensory bias

Question 40

What are indicator mechanisms of intersexual selection?

Answer 40

Females prefer male traits if they “indicate” high viability genes to be inherited by her offspring. Evolution shapes the female's preference.

Question 41

What are resource-based mechanisms of intersexual selection?

Answer 41

Choosy females may benefit directly by acquiring resources (they may acquire more food, protection, and parental care).

Question 42

What is pre-existing sensory bias of intersexual selection?

Answer 42

A male trait or signal is favored because it takes advantage of a pre-existing sensory bias in the female, stimulating her to mate and giving the male a reproductive advantage.

Question 43

What is direct fitness?

Answer 43

The number of an individual’s own offspring that survive and reproduce, thus carrying that individual’s alleles into the next generation.

Question 44

What is indirect fitness?

Answer 44

The number of an individual’s relatives’ offspring that exist because of the individual’s help, weighted by how closely related they are.

Question 45

What is altruism?

Answer 45

Behavior that decreases the fitness of the actor and increases the fitness of the recipient.

Question 46

When are altruistic behaviors favored?

Answer 46

Altruistic behaviors are favored if they increase the survival or reproduction of relatives, who share genes.

Question 47

Inclusive fitness?

Answer 47

sum of direct + indirect fitness

Question 48

What is Hamilton's Rule?

Answer 48

Hamilton’s Rule predicts when an altruistic behavior will evolve. Br - C > 0.

Question 49

What do the variables in Br - C > 0 mean?

Answer 49

Br- Benefit to recipient C- Cost to actor

Question 50

What are three ways in which altruism is likely to spread?

Answer 50

1. Benefits to the recipient are great. 2. Cost to the actor is low. 3. Participants are closely related.