Evolution & Behaviour

Question 1

Define evolution.

Answer 1

Change in the frequency of alleles (form or variant of a gene) in a population over generations.

Question 2

AA and aa are _____ and Aa is _____.

Answer 2

Homozygous; heterozygous.

Question 3

According to Dugatkin (2008), what are the three foundations of animal behaviour? What is important to note about them.

Answer 3

Natural selection (“reproductive success”): species-level adaptation(s).

Individual learning: individual-level adaptation(s); “experience.”

Cultural transmission: Social learning (well documented in cetaceans and primates, arguably in other species), that will become trans-generational (communicated between generations).

Social learning does not equal cultural transmission.

Question 4

What five fields provide evidence for evolution?

Answer 4

Molecular genetics.

Embryology.

Anatomy & morphology.

Biogeography.

Paleontology/paleobiology.

Question 5

What are the two levels of evolution?

Answer 5

Microevolution: changes in gene frequencies or traits occurring in small increments (and often rapidly) at the population or species level.

Macroevolution: major changes occurring at, or above the species level.

Question 6

Artificial selection (selective breeding) is, basically, what?

Answer 6

Microevolution controlled by humans.

Question 7

Define mutations and genetic recombinations.

Answer 7

Mutations: alterations of the genetic material: gene mutations or chromosomal mutations (aberrations). Important in unicellular and asexual organisms.

Genetic recombination: cross-over (combination of alleles); does not increase gene or allele frequency, but increases variability.

Question 8

Define gene flow (migration). What is it mostly determined by and what effect does it have?

Answer 8

Exchange of genes between populations of a species. Individuals (with differential gene frequency) go from one population to another. Mostly determined by biogeography. Stabilizing effect on genetic variation.

Question 9

Define genetic drift. Where is it common?

Answer 9

Alteration of gene frequency through sampling or random fluctuations (chance factors involved) and loss of genes (i.e., loss of genetic variability). Common in small populations.

Question 10

Define the founder and bottleneck effects.

Answer 10

Founder effect: a population becomes reproductively isolated.

Bottleneck effect (e.g., via hunting and fishing): a population bottleneck is a radical reduction in population size leading to a over-representation or under-representation of some characteristics.

Question 11

Interruption of gene flow by physical barrier (barriers to interbreeding) equals what?

Answer 11

Allopatric speciation.

Question 12

What can follow genetic drifts?

Answer 12

Reproductive Isolating Mechanisms such as Specific-Mate Recognition System.

Question 13

What may be a behavioural reproductive barrier for the creation of new species?

Answer 13

Courtship.

Question 14

Natural selection consists of fitness and functional adaptations. Define these two elements.

Answer 14

Fitness: result of sum of features, increase or decrease likelihood of survival and reproduction.

Adaptations: “features” mentioned above, the survival value of traits.

Question 15

Natural selection “produces” adaptations BUT _____.

Answer 15

Adaptations do not have to be the product of natural selection.

Question 16

The concept of natural selection was first described by which individual and at what points?

Answer 16

Darwin.

On the origins of species (1859), and the descent of Man and selection in relation to sex (1871).

Question 17

What are the two “ingredients” for natural selection?

Answer 17

Trait (phenotype): favoured traits help the individual survive and reproduce.

Selective agent: nature (humans, in the case of artificial selection).

Question 18

What are the four prerequisites for natural selection to operate on a trait?

Answer 18

Variation (including mutations, recombinations, migrations, genetic isolation).

Fitness consequences.

Mode of inheritance.

Limited resources (e.g., food, mates, etc.).

Question 19

Define the three sub-types of fitness.

Answer 19

Darwinian or direct fitness: natural selection = reproductive success > # of offspring (= reductionist definition) > Lifetime reproductive success (LRS, = global definition).

Indirect fitness: based on interactions among conspecifics (e.g., helping behaviour, i.e., offspring of relatives surviving because of the individual’s helping behaviour).

Inclusive fitness: direct fitness (transmission of gametes necessary) + indirect fitness (no transmission of gametes necessary).

Question 20

What are the three types of direct fitness?

Answer 20

Traits improving chances of survival.

Correlated traits (indirect contribution): e.g., pleiotropy, linkage (influence by proximity of genes), epistasis (interaction of genes at different loci).

Traits emanating from sexual selection: e.g., traits improving intrasexual competition.

Question 21

Define single-gene effects, pleiotropy, and polygeny.

Answer 21

Single-gene: one gene associated with one phenotype.

Pleiotropy: one gene associated with more than one phenotype.

Polygeny: many genes associated with a specific phenotype.

Question 22

The combine effect of many genes (and their interaction with the environment) account for most of what?

Answer 22

Observable, measurable differences between organisms.

Question 23

Forces of changes and processes of evolution ultimately affect the _____.

Answer 23

Phenotype.

Question 24

The reproductive success of a species is a good index of the “adaptive value” or “fitness value” of a phenotype. It measures what three things?

Answer 24

Number of offspring.

Number of weaned individuals.

Number of individuals available for mating.

Question 25

Fitness is highly dependent on what? Why?

Answer 25

The environment. A fit genotype in environment A can have a very low fitness in environment B.

Question 26

Members of a population or species possess common phenotypic traits. What are these called?

Answer 26

Adaptations.

Question 27

Competition (intra-specific) for resources is necessary for _____ and _____ if _____are scarce.

Answer 27

Survival; reproduction; resources.

Question 28

Cooperation (intra-specific) and altruistic behaviours mostly take place among what?

Answer 28

Mated pairs or genetically related individuals.

Question 29

Why do raccoons work together, even if they are not mated or genetically related?

Answer 29

Working together yields more food than otherwise.

Question 30

In cooperation and competition, what are four classes of behaviours? How do they work with regards to actors and recipients?

Answer 30

Altruistic: costs to actors, benefits to recipients.

Cooperative: benefits to recipients and actors.

Spiteful: costs to actors and recipients.

Selfish: costs to recipients, benefits to actors.

Question 31

Define symbiology and symbiogenesis. Provide an example of symbiosis.

Answer 31

Symbiology: study of symbiosis.

Symbiogenesis: evolution by symbiosis.

E.g., clownfish with anemones.

Question 32

What are the three types of symbiosis?

Answer 32

Mutualism: inter-specific cooperation.

Commensalism: inter-specific association (one species benefits, other necessarily doesn’t). E.g., humans and mice.

Parasitism: one species (parasite) taking advantage of others (host).

Question 33

In parasitism, what is the parasite dependent on? Give an example.

Answer 33

The host. Will sometimes kill host if necessary for parasite’s life cycle.

E.g., suicidal crickets, worm escapes when cricket dies.

Question 34

Contrary to pop science, what should be noted about symbiosis?

Answer 34

Symbiosis does not equal mutualism.

Question 35

Define evolutionary stable strategies (ESS) and describe the two types.

Answer 35

Strategy that cannot (in the present conditions) be improved and cannot be replaced by another strategy, as long as most members of the population use it.

Pure ESS: single strategy adopted by all members of a population.

Mixed ESS: combination of several strategies adopted by all members of a population.

Question 36

Strategy ≠ tactic. Why is this?

Answer 36

A tactic is the behaviour (or set of behaviours) used to execute the strategy.

Question 37

What are the two subtypes of natural selection?

Answer 37

Kin selection: when individuals differ in their effects on the survival of kin via their parental care or helping behaviour.

Sexual selection: based on mate choice, attraction and competition.

Question 38

What is the name of the scent that indicates kin?

Answer 38

MHC.

Question 39

Kin selection was developed in response to what? Define it.

Answer 39

Group selection: suggests can be altruistic regardless of genetic relatedness.

Question 40

What are two highly contested elements of group selection?

Answer 40

Reproductive restraint: animals abstain from sex when accounting for resources/population.

Prudent predation: animals abstain from predation when have abundant food.

Question 41

E.O. Wilson supported what? Conversely, what did D.S. Wilson support?

Answer 41

E.O. Wilson supported kin selection.

D.S. Wilson supported reciprocal altruism - “help you if you help me later.” Stated kinship a factor, but circumstantial.

Question 42

Psychologists and biologists agreed on multi-level selection. What are the six levels?

Answer 42

Gene level (“selfish gene theory”): reductionist, reduces everything to level of gene.

Gamete level (sperm competition): success depends on health of sperm; does not apply to humans.

Individual level (individual selection).

Mating pair level (sexual selection).

Immediate/extended family level (kin selection).

Group level (group selection): all the above can work, depends on species.

Question 43

What are actual adaptations?

Answer 43

Via natural selection.

Question 44

By-products of adaptations or “carried along traits” (or characteristics) equal what term? Provide an example.

Answer 44

Exaptations.

Gould (1991): language is a by-product of our large brains.

Question 45

What is meant by the term “salvation”?

Answer 45

Period of stagnancy, then quick period of rapid learning.

Question 46

Noise or random effects encompass what three things?

Answer 46

Chance (accidental) mutations.

Sudden environmental changes.

Developmental chance (accidental) effects.

Question 47

Mechanisms of maintenance of non-adaptive traits include what four things?

Answer 47

Gene flow (e.g., immigration).

Pleiotropy.

Linkage: alleles that are on the same chromosome are more likely to be inherited together.

Epistasis: the effect(s) of one gene is/are modulated by one or many others.

Question 48

Regarding evolution, what is the progressivism fallacy? What is evidence against it? Provide an example.

Answer 48

States that traits are adaptive and necessarily heading towards improvements or perfection.

Species with long interval of geological times without any or few phenotypical changes.

E.g., common tree squirrels and elephant shrews: 15 to 20 million years of stasis.

Question 49

What is better terminology for “primitive”? “Advanced”? Why is it recommended to use neutral terminology?

Answer 49

Ancestral. Derived.

Terms like “more evolved” and “primitive” are relative.

Question 50

Evolution does not necessarily means an increase in complexity. Complexity is not necessarily better than simplicity. Why is this?

Answer 50

Complexity may be associated with lack of flexibility or adaptability to rapidly occurring environmental changes.

Question 51

The environment is a passive force and gives no directions. Relevant (i.e., apparently adaptive) genes may not even exist for the concerned species. What does this mean and what is the opposite view called?

Answer 51

Evolution does not have a goal or a purpose.

Opposite view is a fallacy called the “purposivism fallacy.”

Question 52

What is cultural primatology and where was it initiated?

Answer 52

Study of cultural traditions in primates. Initiated in Japan.

Question 53

What are five challenges to some basic principles of natural selection?

Answer 53

Adoption (within or between species).

Altruism with non-kin.

Homosexual behaviour.

Risk-taking behaviour (without obvious gains and with clear risks to survival).

Symbiosis (mainly commensalism and mutualism).