Sex conflict and cooperation Flashcards
What is sex
Any genetic exchange between individuals, it’s the occurrence of meiosis
What is meiotic sex
It’s initiated by the fusion of two haploid gametes to form a diploid zygote, ending in the formation of haploid gametes
What are the costs of sex
-Physiological costs of meiosis
-Risk of producing maladapted offspring
-Cost of mating
-Cost of producing males
What is asexual reproduction
Produces genetically identical clones if the environment is stable
What does recombination allow for
Favourable mutations to be integrated more quickly into the population
What happens if you don’t have recombination
Deleterious mutations accumulate
What is background selection
No recombination/ shuffling. The chromosome with the weakly deleterious mutation becomes fixed in the population
What is Muller’s rachet
Random loss of mutation free chromosomes, population gets worse every generation. Accumulation of deleterious mutations
What is genetic hitchhiking
Deleterious mutations linked to beneficial ones, causes an increase in frequency. both deleterious and beneficial is fixed
What is Ruby in the Rubbish
Linkage between strong deleterious mutation and weakly beneficial one. Weak beneficial one will be lost so process of adaptation is slower
Whats the Hill Robertson effect
Asexual population, causes beneficial mutation to rise in different populations
Whats the benefit of sex
Shuffles the genome to produce new combinations of genes
Whats the co-evolutionary arms race
Between parasite and host. From parasites perspective, the environment is the hosts resistance mechanisms. From the host perceptive, the environment is the parasites method of penetrating hosts defensive mechanism
Empirical evidence for the Red queen hypothesis
Long term studies of evolution of sex of new Zealand snails, parasite has a large fitness consequence
Suggests that high levels of parasitim favour sexual reproduction.
