Lecture 9 Flashcards
(15 cards)
What are the two main types of benefits from mate choice?
Direct and indirect benefits
what are the direct benefits of mate choice?
benefits that directly improve the female’s survival or reproductive success, such as food, nest sites, protection or parental care
what are indirect benefits of mate choice
benefits that improve offspring genetic quality, such as attractiveness or disease resistance
what is the sexy son hypothesis
the idea that females prefer attractive males so their sons inherit good looks, increasing their future reproductive success
How does male ornamentation indicate genetic quality?
Elaborate traits (e.g., bright plumage, long tails) are energetically costly, meaning only healthy males can afford them. This signals good genes and disease resistance.
How does female choice evolve when there is a direct benefit?
Female choice evolves when males provide valuable resources such as food, nesting sites, or parental care, increasing female reproductive success.
How does female choice evolve when there is no immediate direct benefit?
Female choice can evolve through good genes selection, sensory exploitation, or Fisherian runaway selection, leading to indirect genetic benefits for offspring.
What is the sensory exploitation hypothesis?
Males evolve traits that take advantage of pre-existing sensory biases in females, even if those traits don’t signal quality.
What is Fisherian runaway selection?
If females prefer a certain male trait, and that trait gets passed to sons, the preference and trait co-evolve, leading to extreme ornamentation over generations.
What is lifetime fitness?
The total reproductive success of an individual, measured by survivorship, mating success, fertility, offspring production, and offspring survival to reproduction (e.g., Red deer studies).
What is inclusive fitness?
An individual’s own reproductive success plus the reproductive success of close relatives, weighted by relatedness.
How is inclusive fitness different from lifetime fitness?
Inclusive fitness includes benefits to relatives due to the individual’s actions, while lifetime fitness focuses only on direct reproduction.
What is male-female reproductive conflict?
Conflict between sexes over reproductive success, occurring before or after copulation, often due to different fitness interests.
Pre-Copulation Conflict (Before Mating)
Occurs when males and females disagree over when, how, and with whom to mate
Example: Male red-winged blackbirds guard their mates to prevent them from mating with other males.
Post-Copulation Conflict (After Mating)
Happens when one sex manipulates reproductive success after mating.
Happens when one sex manipulates reproductive success after mating.
