Barash Psych 200: Animal Behavior Test 2

Front 1

Uses of Evolution (3)

Back 1

Evolutionary History
Reverse Engineering
Prediction

Front 2

Evolutionary History

Back 2

DNA fingerprinting
Helps to determine future evolutionary changes even if maladaptive.
e.g. human birth canal in pelvis, not abdomen

Front 3

Reverse Engineering

Back 3

See the behavior and try to find out how the behavior came to be
e.g. gulls and eggshells

Front 4

Predicting Behavior

Back 4

Predicting behavior using evolution--an animal will act in a certain way to improve fitness
Only need a small fitness consequence to change behavior (1%)

Front 5

Behavior vs. Fitness graph

Back 5

Behaviors have mathematically determinable consequences/values. A behavior will occur at highest possible net return.

Front 6

Mutations

Back 6

Random mistakes in genetic replication, usually harmful, but about 1 in 1 million are helpful. Mutations are necessary for evolution.

Front 7

2 major sources of genetic diversity in animals

Back 7

1. Sex- mixes genes of 2 individuals
2. Genetic drift

Front 8

Sex

Back 8

Mixing genes of individuals to create an individual that shares one-half (r=.5) of its genes with it's father and one-half (r=.5) with its mother. r=.5 between any parent and child.

Front 9

Genetic Drift

Back 9

Impact of small population size. In a small population, mutations are not as important (occurs too seldom) for genetic diversity as genetic drift. Genetic drift is when a small population looses an allele type because in small population it is not passed on and therefore dies out. This can be harmful to the population as it decreases genetic diversity.
Often occurs on islands

Front 10

Pleiotropy

Back 10

Genes will have many effects. A gene may help to produce optimal and suboptimal traits. If evolution favors a chromosome (collection of many genes) some suboptimal genes may also be favored. Overtime these linkage patterns in the chromosome may be broken up through crossing over so that only the optimal genes are favored.

Front 11

Philogenetic Inertia

Back 11

Individuals are constrained by their genetic history. Sometimes the world changes too fast for animals to keep up.

Front 12

"Arms Race"

Back 12

Natural Selection is an "arms race" because it works on two animals at once. Natural Selection makes the snowshoe hair escape from the lynx, while also making the lynx better at catching snowshoe hairs. However, there isn't equal pressure on both sides. The hair is running for its life, but the lynx is just running for its lunch.

Front 13

Measures of Reproductive Success (4)

Back 13

1. Fecundity- measure of eggs
2. Fertility- number of eggs fertilized
3. number of offspring that survive
4. number of offspring that mat successfully
It is hard to measure how successful a parent is.

Front 14

Honest Communication

Back 14

The goal is to accurately convey reality.
Worker bees telling each other where and the food is

Front 15

Dishonest Communication

Back 15

The goal is to not accurately convey reality.
Animals are selected to manipulate others and avoid manipulation by others
Alarm-calling when there is no predator

Front 16

Inter-species Communication

Back 16

Has more dishonest communication
Dishonest: victory butterflies colors make it look like a monarch, so birds don't eat
Honest: monarch butterflies colors show bad taste OR stotting
In this example, natural selection acts to make monarchs look less like victories and victories more like monarchs

Front 17

Intra-species Communication

Back 17

Dishonest: often occurs in courtship. The fish that courts by showing the female how good at defense he is. He is better at courting than at actually defending.
Honest: alarm-calling marmots

Front 18

Single Gene Effect

Back 18

An effect produced by a single gene. This is more common in simple animals.

Front 19

Polygenetic Effect

Back 19

A given phenotype is produced/influenced by many genes
Hard to breed for polygenetic effects

Front 20

Allele

Back 20

Alternate form of a gene

Front 21

Artificial Selection

Back 21

People selecting animals for specific, human desired, traits.
Example: dogs

Front 22

Altruism

Back 22

Enhancing the fitness of someone else while reducing the fitness of the altruist
Example: alarm calling might call attention to the alarm caller
Often occurs between genetically related individuals. The higher the relationship (r closer to 1), the more altruism. Reciprocity is altruism between genetically unrelated individuals.
Altruism may be selfless because the individual is at risk, but it is often genetically selfish because if r is high, the chances are that the animal they help also has the same genes.
Altruism = BxR>C
Where:
B is benefit
C is cost incurred
r is the probability of shared genes between the altruist and the helped individual. r cannot be less than 0 or greater than 1.
r is much easier to quantify, but that doesn't mean it is more important.

Front 23

Diploid

Back 23

Species that share 1/2 of their genes with their kids

Front 24

Gamete

Back 24

Egg and sperm cells

Front 25

Haploid

Back 25

Species that share all of their genes with their kids

Front 26

r

Back 26

The degree of genetic relationship. 0<r>1.
Identical twins/self: r = 1
Parent and child: r = .5
Siblings: r =.5 (on average)
Half-Sibs: r = .25 (on average)
Aunt/Uncle and Niece/Nephew: r = .25 (on average)
Grandparent and grandchild: r = .25
Cousins: r = .125 (1/8) (on average)
2nd Cousins: r = .03125 (1/32) (on average)
Unrelated: r = 0

Front 27

Haplo-Diploid

Back 27

Females are diploid, males are haploid. In this situation, females share 3/4 of their genes (r) with their sisters (of the same father). Males result from unfertilized eggs and share only 1/4 of their genes (r) with their sisters (same mother, no father). Note that sisters have a higher r than mothers and children. Often in haplo-diploid species, the sisters stay home and take care of their sisters with whom they more genes than they would if they had kids. However, this is not always the case. Some haplo-diploid species (solatiry wasps) are not eusocial and some eusocial species are diploid (termites, hairless molerats)

Front 28

Eusocial Behavior

Back 28

Kin altruism, helping relatives with reproduction while delaying/forgoing reproduction
Examples:
Eusocial behavior: "nest helpers"
Extreme eusocial behavior: ants, naked mole rats, termites, some wasps, bees

Front 29

Darwinian Fitness

Back 29

Reproductive success

Front 30

Inclusive Fitness

Back 30

Success of genes (in an individual and an individual's kin)

Front 31

Reciprocity:

Back 31

Altruism that occurs between non-related individuals (r = 0). With reciprocity, cheating is a problem.
Example: vampire bats sharing meals.