Topic 7.4 - Population Genetics 𖦹⋆｡°✩ Flashcards
what is a mutation
a random change in an organism’s genome
what can mutation contribute to
changes in the genetic makeup of a population overtime
what can mutations lead to
create genetic variation within a population
what do mutations provide
new phenotypes that contribute to evolution by natural selection
what is genetic drift
the random change in the frequency of a particular allele within a population
is genetic drift nonselective
yes, it is a nonselective process that generally occurs in small populations
what are some examples of genetic drift
༻ increased death rates and low reproductive rates
༻ natural catastrophes (fires, volcanic eruptions, etc)
what contributes to genetic drift
bottleneck events
what is a bottleneck event
when a large, diverse population is suddenly reduced to a small population
what is a founder effect
a random process that reduces genetic variation within a small population due to separation from a larger population
what can isolate populations
migration and geological events
can the genetic makeup of a founder population differ from the original population
yes
what is migration/gene flow
the movement of individuals between populations causing an exchange of alleles between populations
what does migration introduce and what does it lead to
introduces new genes into populations and increases genetic variation
what does continued migration between populations lead to
reduces genetic diversity between populations overtime
what is the raw material of evolution
genetic variation
what is fitness relative to
specific environmental conditions
how can fitness change
as conditions change
how can different phenotypes be selected for/against
according to changes in the environment
when can evolution of a population NOT occur
if there is no genetic variation within the population
what is a null hypothesis
states experimental variables have no relationship and experimental observations are the result of chance
what is an alternative hypothesis
states that experimental variables have a relationship and the experimental observations are the result of some nonrandom cause
