Intro to Behavior

Question 1

Logic of Darwin’s Reasoning?

Answer 1

Living organisms could increase their numbers geometrically, but they don’t (“struggle for existence”), variation exists among individuals in every species, inheritance, variations that result in greater survival and reproduction will increase in frequency over time

Question 2

What does evolution not equal?

Answer 2

Natural selection

Question 3

Evolution equals

Answer 3

gene or allele frequency change - mutation, migration, genetic drift, natural selection

Question 4

Natural selection equals

Answer 4

differential genetic success “fitness”

Question 5

Organisms are __________

Answer 5

Reproductively selfish

Question 6

Animals behave in ways that enhance survival and reproduction of their…?

Answer 6

Own genetic material, even if it’s detrimental to population or species

Question 7

Can behavior change over time?

Answer 7

Yes - behavioral evolution

Question 8

Example of behavioral evolution

Answer 8

Oceanic field cricket had a change in wings and behavior. Longer and faster songs = higher parasitism rates… wing morphology changed and they became song absent… adopted new strategy of coming near crickets that were song present to find mates, but far enough away to not be seen by the parasitic fly

Question 9

Lifetimes are sequences of….?

Answer 9

Unconscious cost/benefit decisions about how to maximize reproduction (i.e. behavior)

Question 10

Evolution leads to new variants and/or change in frequencies of variants in the next generation. What are the new variant evolutionary forces and what are the change in frequency of variants evolutionary forces?

Answer 10

New variant evolutionary forces: Mutation & migration/gene flow
Change in frequency of variants evolutionary forces: Genetic drift & selection

Question 11

Mutation

Answer 11

Random, most deleterious, new alleles
Mutation puts deleterious alleles in population and selection acts to remove them… mutation-selection balance

Question 12

Migration/Gene flow

Answer 12

Homogenizes populations, movement of alleles from one population to another by movement of individuals or gametes. Will counteract differentiation (ex: local adaptation). It can both cause and prevent evolution

Question 13

Genetic drift

Answer 13

Chance changes in allele frequencies, i.e. mortality, disease, predation, failure to mate, difference in offspring numbers, natural disaster. Unrelated to phenotypic variation. Small populations magnify genetic drift and it can oppose selection.

Question 14

What evolutionary force is the only force that predictably leads to adaptation?

Answer 14

Natural selection

Question 15

Should we think in terms of reproductive success or genetic success? Why?

Answer 15

Terms of genetic success because genetic success is exact description and always right. There are organisms that do not behave in ways that enhance their reproductive success.

Question 16

List some examples of animals that do not favor reproductive success

Answer 16

Meiotic drive in fruit flies and honeybee workers

Question 17

What are two ways to achieve genetic success?

Answer 17

Produce own offspring –> direct genetic benefits
Help relatives produce offspring –> indirect genetic benefits

Question 18

What are replicators?

Answer 18

Entity which can be copied (genes, ideas, etc.), potentially immortal, information/software

Question 19

What are vehicles?

Answer 19

The survival machines of replicators (plants, animals, etc.), tangible stuff/hardware, mere mortals

Question 20

Selfish genes do not make _____

Answer 20

Selfish organisms

Question 21

What are the two levels of questions?

Answer 21

Proximate and Ultimate

Question 22

Proximate questions

Answer 22

Immediate cause questions - “how does behavior occur”

Question 23

Ultimate questions

Answer 23

Long-term cause questions - “why does a behavior occur”

Question 24

What are Tinbergen’s 4 types of questions?

Answer 24

Mechanistic, ontogenetic, functional, evolutionary

Question 25

Mechanistic (Tinbergen’s first level of analysis)

Answer 25

How does it work physiologically, cognitively?

Question 26

Ontogenetic (Tinbergen’s second level of analysis)

Answer 26

How does the behavior develop? What are the roles of genes and learning?

Question 27

Functional (Tinbergen’s third level of analysis)

Answer 27

How has natural selection shaped the behavior? How does it effect fitness?

Question 28

Evolutionary (Tinbergen’s fourth level of analysis)

Answer 28

How has the behavior evolved over time? What are the ancestral characters and how have they evolved?

Question 29

Phylogenetic tree

Answer 29

A diagram showing relationships of ancestry and descent. Composed of lineages, lineages are composed of individuals of a species through time, individuals express characters

Question 30

Character vs character-state examples

Answer 30

Character: song, larval activity, eye color parental care
Character-state: present/absent, low to high

Question 31

Parsimony

Answer 31

The phylogenetic explanation for the character observations across taxa requiring the fewest number of changes

Question 32

Homology

Answer 32

A trait that is possessed by two or more species that was inherited, with or without modification, from their common ancestor. Ex: short tail between bears, seals, and foxes

Question 33

Analogy

Answer 33

Convergent trait. Traits that are similar in function but have independent origins. Ex: birds having courtship songs and crickets also having courtship songs

Question 34

Strong inference (Platt)

Answer 34

Make multiple hypotheses to avoid attachment to a favored hypothesis and design an experiment to eliminate more or more alternative hypotheses