what are some cost of mating and meiosis?
finding mate consumes time and energy and cost of meiosis is that recombination breaks up favorable gene complexes.
what are some benefits of sex?
prevents muller ratchet
deleterious mutation accumulate in asexual lineages not sexual
providing long term benefits
creation of novel gene combination
red queen hypothesis
: must constantly create new gene arrangement to combat pathogen evolution
providing short term benefits
what are some types of sex determination?
genetic ( either chromosomal or genic)
what is the mechanism of haplodiploidy?
haplodiploid males develop from unfertilized egg
diploid females develop from fertilized eggs
what is social sex determination?
it depends on the mating system
many fish can undergo sex reversal
dominant female in sea bass changes into male when territorial male disappears.
what is protogyny?
starting life as female and then changing to male
what is protandry?
where male function precedes female function
what is the null model for sex allocation?
parental strategies should evolve towars equal investment in offspring of the two sexes.
if sex ratio falls below 50% increased production of rare sex is favored
what is the adaptive sex ratio bias?
maternal condition influences offspring investment ( trivers willard effect)
local mate competition
local resource competition
local resource enhancement
what is trivers willard effect?
population sex ratio is 1:1, individual sex allocation depends on condition
if moms in good condition transfer competitive ability to sons more than daughter.
dominant individual sir more offspring
they produce more sons then daughters
female in poor condition should produce more daughters