Sexual selection 2- Week 3, part 2- Choice for direct benefits. Flashcards
Mate complementarity:
What is complementarity?
In order to produce offspring, what needs to happen?
Why?
What does complementarity improve?
What is an exception?
Mating with members of the same species.
Mate with those from the same species as you.
Breeding with another species does not produce viable offspring.
Offspring number (direct benefit).
A mule (donkey + female horse).
Continuation with mate complementarity:
Are some species able to be confused with each other?
What is dangerous?
Give an example of spider species that look the same.
Yes.
When males in different species look similar.
Jumping spider species- males do courtship dances- sometimes direct it to females of another species.
Continuation with mate complementarity:
For reproduction to happen, what needs to happen?
Name a species where the males and females look very different.
How do mammals like rodents, in which males and females look similar, tell who is a male and who is a female?
Mate with members of the opposite sex.
Pea hens and peacocks.
Done through things like smell.
Mate fecundity/fertility:
In newts, what is there a correlation between?
When a male wiggles their tale a lot (intensity), what does this tell females?
Why do females need to know this?
How do females select for high fertility?
What are they doing here?
Correlation between amount of courtship dances (impressiveness) + sperm supply.
Their sperm supply.
She may be laying a lot of eggs + needs them fertilised.
By looking at courtship dance.
Exerting choice for high sperm supply.
Choice for high fecundity or fertility:
What can males be?
What does this go under?
Give an example of a male animal which is choosy.
Why?
Choosy.
Sex role reversal.
Mormon crickets.
They produce spermatophores- costly- want to give it to large females who produce more eggs.
Continuation with choice for high fecundity or fertility:
What is a spermatophore?
What is a spermatophore considered as?
What is the issue with a spermatophore?
How much body weight do males lose when they give a spermatophore?
A bundle of nutritional stuff- females eat it- whilst mating.
A nuptial gift (snack for the female).
Takes a lot of energy to make.
25% of body weight.
Choice for immediate gains:
What are females essentially doing?
Give examples of nuptial gifts.
What can females do?
Making males pay for mating with them.
Spermatophores, dead insect + saliva (scorpion fly) + dung (dung beetles).
Exert choice- pick male with the best gift.
Continuation with choice for immediate gains:
What happens in a black tipped hanging fly?
How is the sperm delivered?
What does having a big gift lead to?
What are females using?
Size of nuptial gift- determines mating duration.
Consistently over a period of time.
Big gift- long mating- more sperm transferred- more eggs fertilised.
Rule of thumb- when stop eating, stop mating.
Continuation with choice for immediate gains- Male sexual suicide:
What spider does sexual suicide?
What happens?
What happens if he resisted?
Would the male have died anyways if not eaten by the female?
Who is bigger; the male or female?
Male Redback spider.
After mating, the female eats the male- whilst sperm transfer takes place.
They will not mate- he will not leave any descendants.
Yes.
Female.
Continuation with choice for immediate gains:
Are gains always food?
What can they be?
Why is rocks useful for adelie male penguins?
No.
Rocks.
Make nests- better ones, shows you are a better mate.
Continuation with choice for immediate gains:
What do female adelie penguins do?
Why do they mate with extra males?
What does this show?
Are bird colonies paired up?
Have a partner but mate with others (extrapair copulation).
Get nest materials (rocks).
Females can benefit from mating with multiple males.
Yes.
Choice for resources:
Give an example of a resource.
What do females choose?
Why do females want males with the best territories?
Who benefits from picking high ranking individuals?
Give an example of animals which defend territories (ponds).
Territories.
Mates with the best territories.
Place to rear offspring.
Males and females.
Bullfrog.
Parasite avoidance:
What is this?
For this part, what is this not related to?
Give an example of an animal which does parasite avoidance.
Avoiding males who have parasites so you do not catch it.
Nothing to do with males having genetic qualities that make them resistant to parasites- here is a direct benefit.
Broadnosed pipefish- males want females will less parasites- not to do with offspring.
Parental care:
What is a species where males provide parental care?
In 3-spined sticklebacks, what do females prefer?
Why?
Jaw fish.
Males with redder bellies.
Cue for parental care- eggs will be looked after more effectively.
Protection:
Who can protection be from?
Give an example of an insect which provide protection from predators.
Did females pick males who will protect them?
Give an example of an animal which provides protection from other males of the same species.
Predators or other members of the same species.
Field crickets- when predators comes, females get into burrow first and males guard the entrance.
Yes.
Southern elephant seals- the male monopolising access to the females fights the invading male away.
