Chapter 17 Flashcards Preview

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Flashcards in Chapter 17 Deck (19):
1

Two types of sexual selection?

Intersexual and Intrasexual

2

Intersexual selection?

Individuals of one sex select among individuals of the other sex as mates

*choosier ones tend to be females*

3

Intrasexual selection

Members of one sex, most often males, compete with each other for mating access to the other sex

4

Three types of mating systems?

-monogamous
-polygamous
-promiscuous

5

Monogamous

Male and female mater with each other and only each other during a given breeding system (can be lifetime or seasonal)
*think of humans*

6

Polygamous

Either males or females have more than one mate during a given breeding season or cycle

*can be polygyny or polyandry*

7

Polygyny

Males mate with more than one female per breeding season

8

Polyandry

Females mate with more than one male per breeding season

9

Promiscuous

Both polyandry and polygyny, occurring at the same time

10

Polygynandry

Several males form pair bonds with several females simultaneously

11

What is the limiting resource for selective processes?

Eggs are limiting resource, so males should compete for access
&
Females should be choosier sex because eggs are expensive

12

What is the difference between males being chosen by multiple or few to no females?

Multiple= high reproductive success
few or none= low reproductive success

13

Amplexus

Pre-mating ritual in which males and females are joined together often with one individual on the back of the other

14

Good genes

genes that code for some suite of favorable traits

15

What are the two types of parasites & define them:

Ectoparasites: live on OUTSIDE of organism
Endoparasites: live on INSIDE of organism

16

Hamilton-Zuk hypothesis

Body coloration is a good proxy of parasite overload. Healthy males tend to be colorful, while diseased males are duller.

17

Runaway sexual selection

A gene that codes for a particular trait in males that over time becomes associated with a gene that codes for a particular behavioral mating preference in females.

(linkage disequilibrium arises between alleles for male phenotype and female preference)

18

Sensory exploitation model

Females initially prefer a certain male trait but not because of any mating benefit that is associated with that male trait.

(female's nervous system responds to trait because that's how they're "wired").

19

Sexual conflict

When differences in selection on males and females is great, traits that evolve in one sex may be detrimental to individuals in the other sex