Topic 3 Animal Behavior: Social Behavior

Question 1

• This consists of threats, aggression, and submission. Agonistic behavior originates from competition for food, mates, or territory. Agnostic behavior is ritualized, so injuries and time spent in contests are minimized

Answer 1

1. Agnostic Behavior

Question 2

• Animals in a hierarchy have different levels of power and status depending on their rank in the group. Having a hierarchy does minimize fighting for food and mates
• Pecking order - a linear order of status used to describe the dominance hierarchy in chickens

Answer 2

2. Dominance Hierarchies

Question 3

• The active possession and defense of territory to ensure adequate food and place to mate

Answer 3

3. Territoriality

Question 4

• This is seemingly unselfish behavior that appears to reduce the fitness of an individual. An example of altruistic behavior is when an animal risks its safety in defense of another, or when an animal helps another individual of the same species to rear its young. Altruistic behavior actually increases inclusive fitness. Inclusive fitness is the fitness of an individual plus its relatives who share some identical genes.

Answer 4

4. Altruistic Behavior

Question 5

a. Kin Selection
b. Reciprocal Altruism
c. Hamilton’s Rule

Answer 5

Types of Altruistic Behavior

Question 6

• This is natural selection that increases inclusive fitness. Examples of kin selection are:
  a. When a squirrel sounds an alarm when a predator comes. This is risky to that squirrel and reveals its presence, but this action saves its daughters, mothers, sisters, and aunts
  b. In bees, males are haploid (born from an unfertilized egg of a queen) and female workers and queens are diploid (from fertilized eggs). Females are highly related to each other because they have the same father whose genes all come from a queen mother. Inclusive fitness of female workers is greater if she promotes production of sisters by nurturing the queen than if she produced her own offspring

Answer 6

a. Kin Selection

Question 7

• This is when unrelated members of the same species help each other. This tends to be in species with stable social groups that are likely to meet again, thus there is potential future benefit

Answer 7

b. Reciprocal Altruism

Question 8

• The principle that for natural selection to favor an altruistic act, rB > C. (r) is the genetic relatedness between the altruist and the relative. (B) is the amount of genes the relative can pass on after it is helped by an altruist. (C) is the altruist’s direct fitness, which is the number of genes that animal can pass on by itself, disregarding relatives. If when (r) and (B) are multiplied is greater than (C), then altruistic behavior can occur

Answer 8

c. Hamilton’s Rule

Question 9

• Is a pacifying social behavior that seeks to pacify aggression or to avoid being attacked by showing an inferior social stance (e.g., moving/turning away).

Answer 9

Appeasement Behavior

Question 10

1. Monogamy - one male mating with one female
2. Polygamy - can be split into polygyny (one male mating with multiple females) and polyandry (single female mating with multiple males)

Answer 10

Mating systems

Question 11

• Is when individuals in a population copy the mate choice of others.

Answer 11

Meat-choice Copying

Question 12

• Evolutionary game theory refers to the successful outcome of mating depending on dynamic, constantly shifting strategies of all the individuals involved. In evolutionary terms: the fitness of a particular behavioral phenotype is influenced by the behavior of other phenotypes in population. One common example of game theory in biology is the side- blotched lizard population with three different throat colors. The orange colored lizards are aggressive and mate with numerous females across large areas. The yellow colored lizards are more passive and closely resemble female lizards, allowing them to sneak into the territory of orange lizards, successfully mate, and eventually take majority control of the population. The blue colored lizards mate with only one female lizard but guard them closely - they are unable to compete against orange lizards, but their closeness to their mate prevents yellow lizards from being able to sneak in and take over. Thus there is a constantly shifting majority population due to the rock-paper-scissor like dynamic at play: orange lizards can overcome blue lizards due to their aggression, but are susceptible to being taken over from within by yellow lizards. Yellow lizards can overcome orange lizards through their sneaky behavior, but are unable to fool blue lizards. Blue lizards cannot be fooled by yellow lizards, but can be defeated in combat by orange lizards. The majority lizard color within any given population is therefore always shifting based on the prevailing lizard group and its individual strengths/weaknesses

Answer 12

Game Theory

Question 13

• Is a one-shot, big-bang reproduction. Many offspring are produced in a single reproductive opportunity. The survival rate of offspring is low but there is a higher number of offspring. This method is better for variable and unpredictable environments. Salmon exhibit semelparity

Answer 13

Semelparity

Question 14

• Is repeated reproduction. There are relatively few but large offspring each time reproduction occurs. The parents tend to care for their offspring so the offspring survival rate is higher. This method is more favorable in dependable environments where adults are likely to survive and breed again, and competition for resources may be intense. Humans exhibit iteroparity.

Answer 14

Iteroparity