Flashcards in BIO220 Lecture 3 Deck (50)
How to test indirect benefit hypothesis?
Female identifies preferred male trait. Mate her to ones with best trait and worst trait. Examine offspring.
how are sex roles defined?
Resource investment in the offspring
Examples of high male PI?
- Giant water bugs
- Spotted sand piper
Pipefish male reproductive success limited by...
size of their brood pouch
Pipefish female reproductive success limited by...
access to males' brood pouch
Mating system of pipefish
Females compete and are sexually selected for by the males
What do male pipefish look for?
Larger females (more eggs) & large fold
Katydid mating system (normal)
Males transfer spermataphores to female
Katydid mating system (low resources)
Females need male for spermataphores, and males limited by the resources to make spermataphores.
Males become the limiting factor.
Females will be sexually selected.
What changes when food is scarce for katydids?
- Male calls decrease
- Females mate more
- Male mate choice increases
- Female competition increases
Major histocompatibility complex
What does MHC do?
Code for antigen recognition system of the immune system
Loci that code for antigen recognition (immune response)
MHC in humans is...
What kind of MHC is good?
Ones with lots of genetic variation -> defend against more pathogens
Why do mice choose mates based on MHC?
- Avoid inbreeding
- Increase genetic diversity at MHC loci
Do mice choose mates based on MHC?
Yes; mate choice based on odours that correspond with differences at MHC loci
Are humans affected by odours that correspond with HLA?
What were the results of the odour study in humans?
- Intensity of odours similar between different HLA and same HLA group
- Women prefer those with different HLA