Mechanisms of evolution Flashcards
Kin selection
When individual decreases its own fitness to improve the fitness of those who share a proportion of its genes.
Evolutionary fitness
Organisms ability to have more offsprings than others in a population
Inclusive fitness
Sum of individuals fitness plus close family members fitness
Altruism
Behavior of an animal that benefits another’s at its expense
Genetic drift
Changes in the gene pool of a population due to some random chance event
Bottleneck effect
Changes in gene pool due to some random chance event(usually a natural disaster) reduces the population drastically and survival is random
Founders effect
New population is formed by very small group of people called founders, different than bottleneck in that the original population still exists they are just geographically isolated from each other
Inbreeding
May result from founder’s effect, it is the non random mating between close relatives who share more of the same alleles.
Results of inbreeding
Overtime genetic variety reduces and individuals may be homozygous for recessive allele with harmful effects
Recessive traits
Need two copies of the same allele to be expressed
Homozygous
Carry the allele and express it
Gene flow
Movement of alleles between population, introduction new genetic material on which natural selection can act
What Mutations are passed onto offsprings
Mutations in gametes( sex cells)
Causes of mutations
Spontaneous and mutagens(agents that cause mutations us usually carcinogens)
Sexual dimorphism
Distinct Differences in size and appearance between sexes of an animal in addition to difference between the sexual organs
