social behaviors

Question 1

social behaviors

Answer 1

interactions with members of one’s own species, including mates, offspring, other relatives, and unrelated individuals

Question 2

predator detection/evasion (group benefits)

Answer 2

a group may be able to fend off predators better than an individual

Question 3

dilution effect (group benefits)

Answer 3

the reduced, or diluted, probability of predation to a single animal when it is in a group
-probability of death = 1/group size

Question 4

vigilance-group size effect (group benefits)

Answer 4

more individuals watching for predators allows each individual to spend less time watching and more time feeding

Question 5

food location (group benefits)

Answer 5

many individuals teaching for food may be able to find rare food more easily
-probability of prey capture may increase in a group

Question 6

mate finding (group benefits)

Answer 6

being social makes it easier to find potential mates because large groups attract the attention of the opposite sex

Question 7

lek

Answer 7

the location of an animal aggregation to put on a display to attract the opposite sex

Question 8

predation (group cost)

Answer 8

groups of animals are more conspicuous to predators

Question 9

disease transmission (group cost)

Answer 9

the risk of parasites increases in groups
-high densities can increase the rate at which diseases spread

Question 10

competition (group cost)

Answer 10

larger groups are better able to locate food, but that food must be shared among all members

Question 11

aggression (group cost)

Answer 11

living in groups can lead to aggression among members

Question 12

balancing costs and benefits

Answer 12

optimal group size
-not too big or too small

Question 13

territoriality common

Answer 13

mobile species, limited resources

Question 14

territoriality uncommon

Answer 14

high population density, unpredictable resources
-benefits of group living

Question 15

dominance hierarchy

Answer 15

a social ranking among individuals in a group, typically determined through contests such as fighting or other contests of skill and strength
-occurs when defending a territory is impractical
-saves energy by decreasing duration of subsequent contests

Question 16

donor

Answer 16

the individual who directs a behavior toward another individual as a part of a social interaction

Question 17

recipient

Answer 17

the individual who receives the behavior of a donor in a social interaction

Question 18

cooperation

Answer 18

donor = increased fitness
recipient = increased fitness
(herd of lions kill prey)

Question 19

selfishness

Answer 19

donor = increased fitness
recipient = decreased fitness
(competition for food)

Question 20

altruism

Answer 20

donor = decreased fitness
recipient = increased fitness
(between relatives)

Question 21

spitefulness

Answer 21

donor = reduced fitness
recipient = reduced fitness
(does not occur in natural populations)

Question 22

altruism does not lead to direct fitness

Answer 22

fitness an individual gains by passing on copies of its genes to its offspring

Question 23

indirect fitness

Answer 23

the fitness that an individual gains by helping relatives pass on copies of their genes

Question 24

inclusive fitness

Answer 24

the sum of direct fitness and indirect fitness

Question 25

direct selection

Answer 25

selection that favors direct fitness

Question 26

indirect selection (kin selection)

Answer 26

selection favoring indirect fitness

Question 27

coefficient of relatedness

Answer 27

the probability of an individual and its relative carrying copies of the same genes from a recent common ancestor

Question 28

eusocial animal characteristics (4)

Answer 28

1. several adults living together in a group
2. overlapping generations of parents and offspring living together in the same group
3. cooperation in nest building and brood care
4. reproductive dominance by one or a few individuals, and the presence of sterile individuals

Question 29

caste

Answer 29

individuals within a social group sharing a specialized form of behavior

Question 30

queen

Answer 30

the dominant, egg-laying female in eusocial insect societies
-typically mate once during their lives
-sons are made by laying unfertilized eggs and daughters are made by laying fertilized eggs (haplodiploid system)

Question 31

haplodiploid

Answer 31

a sex determination system in which one sex is haploid and other sex is diploid

Question 32

offspring remain sexually immature until

Answer 32

the king or queen dies

Question 33

in mole rats why are offspring not willingly subordinate

Answer 33

the dominant female harasses offspring, which increases stress, reduces levels of sex hormones, and makes them less motivated to breed

Question 34

eusociality has independently evolved many times, how can it evolve

Answer 34

if the cost of leaving a colony is high due to a low likelihood of surviving