Behavioral Ecology

Question 1

Shared vigilance

Answer 1

More eyes. Each individual in a group must spend less time watching and can spend more time feeding.

Question 1

Groups

Answer 1

Purposeful joining of individuals. Increase the chance of surviving, feeding, or finding a mate. Increased rate of resource depletion. Optimal grouping behavior balances these factors.

Question 2

Shared defense

Answer 2

Group attacks on potential predator in a group.

Question 3

Numerical Dilution Effect

Answer 3

reduced probability of predation for an individual during a successful attack on a group.

Question 4

Confusion Effect

Answer 4

Difficult for predators to focus on one out of many moving prey

Question 5

Benefits of groups in mating

Answer 5

Large groups attract the attention of females.

Question 6

Lek

Answer 6

Place animals aggregate, display and attract the opposite sex

Question 7

Territory and dominance hierarchies

Answer 7

Organize resource access. Dominant individuals get more

Question 8

Interactions in a group require …

Answer 8

energy

Question 9

Spitefulness

Answer 9

Maladaptive. Reduces the fitness of both donor and recipient. Not observed in natural populations

Question 10

Selfishness

Answer 10

Donor experiences increased fitness, recipient experiences decreased fitness. Ex. Intraspecific competition for space.

Question 11

Cooperation

Answer 11

Donor and recipient both experience increased fitness. Cooperation is common. Hunting, heat conservation, feeding by two parents.

Question 12

REVIEW THE GAME THEORY PAY-OFF GRID FROM DISCUSSION

Answer 12

REVIEW THE GAME THEORY PAY-OFF GRID FROM DISCUSSION

Question 13

Altruism

Answer 13

Cost to donor. Benefit to recipient. Selfless behavior. Does not lead to direct fitness. The fitness an individual gains by passing on genes to its offspring. We would expect selfishness to prevail over altruism.

Question 14

Altruism is really … because …

Answer 14

Apparent altruism. The idea that altruistic acts may actually be cooperative. The donor may eventually benefit. Two main mechanisms proposed (reciprocal, kin)

Question 15

Reciprocal altruism

Answer 15

Expectation that the other organism will act in a similar manner at a later time.

Question 16

Kin selection

Answer 16

Altruistic behavior increases the fitness of a relative and in so doing indirectly increases the fitness of the altruist

Question 17

Indirect fitness

Answer 17

the fitness an individual gains through the reproduction of their relatives which passes on copies of their genes (can be increased by helping behaviors).

Question 18

Inclusive fitness

Answer 18

The mathematical sum of direct and indirect fitness.

Question 19

Hamilton’s Rule

Answer 19

Benefit to the genes of the donor must be greater than the cost.

Question 20

Hamilton’s equation

Answer 20

r > C/B

Question 21

Eusociality

Answer 21

Highest grade of sociality. Most offspring help parents rear siblings rather than reproduce themselves. Some organisms have no direct fitness, only indirect (& thus inclusive) fitness. Cooperation not altruism. Reproductive dominance and sterile castes.

Question 22

Eusocial Hymenopteran Societies

Answer 22

Many (not all) bees, wasps, and ants

Question 23

Characteristics of Eusocial Hymenopteran Societies

Answer 23

One or a few egg-laying female queens. Non-reproductive female workers gather food and care for younger siblings Male offspring (drones) and new queens sexually mature and leave the nest.

Question 24

Haplodiploidy in Hymenoptera

Answer 24

Daughter egg is fertilized by drone which is diploid. Drones come from unfertilized egg and is haploid. Drones must give some DNA to all daughters. Hymenopteron sisters are 0.75 in relatedness so it makes sense for the worker bees to be sterile and raise queen offspring.

Question 25

True or false: Haplodiploidy is necessary for eusociality

Answer 25

False. It is favored but not necessary.

Question 26

Diploid Eusocial Species

Answer 26

Termites, mole rates

Question 27

Eusociality also favored when cost of staying with a colony is … and cost of leaving due to mortality is …

Answer 27

low, high