19 - Evolutionary Conflict and Cooperation Flashcards
Name 3 family conflicts
- mate conflict
- parent-offspring
- sibling conflict
Why do family conflicts happen?
- differences in investment of gametes in male and female parents
- investment needed in offspring success
When does a male benefit from females?
- they invest in his offspring
- they invest in current reproduction
When does a female benefit from males?
- produce offspring with best quality of male
- get the greatest investment or least harm from males
What is the effect of investing in offspring on male mating opportunities?
- reduces mating opportunities for males more then females
Explain parent-offspring conflict
- offspring want as much resources from parents
- parents want to invest the least amount possible
What are genomic conflicts within an organism?
- paternal DNA -> wanting to get as much resources as possible
- maternal DNA -> DNA is shared with siblings. May want to limit resources extracted
Explain Igf2 in rats
- Igf2 activated in paternal DNA, deactivated in maternal DNA
- if Igf2 receptor activated, inhibits Igf2, turned of in males and on in females
What is interlock sexual conflict?
- male and female traits that interact are controlled by different loci
What is chase away sexual selection?
- inter-loci sexual conflict
- males evolve methods to damage females
- females fight back
What can selective advantage for male genes cause females to do?
- use his sperm instead of competitors
- immediately after mating produce more eggs or better eggs
- reduce mating (decrease attractiveness or receptivity)
What is intra-locus sexual selection?
Male and female traits have different optima controlled by the same locus
What is intra-locus sexual antagonism?
- poor males make fit daughters
- fit males make poor daughters
- average make average
Explain intra-locus sexual antagonism in terms of selection coefficients
perfect male = 1
perfect female = 2
- female that inherits both male loci will be 1 - t
- male than inherits both female loci will be 1 - s
- if they are heterozygous it will be 1 - h(f or m) x (s or t)
h = dominance
What is required for intra-locus sexual selection?
s and t > 0
Explain sex chromosome linkage if the loci is at the pseudoautosomal region
- if at loci in pseudoautosomal region then crossing over between X and Y can happen
- will inherit one chromosome form mum, other could be either the allele on X or Y by crossing over
Explain sex chromosome linkage if the loci is not at the pseudoautosomal region
- one chromosome from mum, dad can only offer up the two chromosomes with no crossing over
How does sex chromosome linkage lead to shrinkage of the Y chromosome?
- there is a selective advantage to removing alleles from the pseudoautosomal region
What are 4 possible explanations for altruism?
- collective self interest - benefits individuals
- mutual benefit - can be repair later (reciprocal altruism)
- group selection
- kin selection
What is group selection and the cons?
- doing thins for the good of the group
- unit of selection on the group
Cons
- as you reach carrying capacity, reproduction slows and stops
- dominant females evict pregnant subordinate females
- not evolutionary stable
What is an evolutionary stable strategy?
- strategy that when adopted by the population, cannot be invaded by any alternative strategy
What is r?
- coefficient of relatedness
- the probability that an allele present in a n individual is also present by common decent in its relatives
What does a large and small r mean?
large = closer related
small = less related
what relation is r = 1?
yourself
