Genetic drift Flashcards
gene flow
the movement of alleles between individuals from two different populations through eith migration/immigration/emigration
immigrants effect on population
add new alles to gene pool, increases genetic diversity
emigrants effect on population
may remove or completely change the frequency of alleles, decreases genetic diversity
how can migration occur
when the populations are physically close together or due to external forces
types of genetic drift
the founder effect and bottleneck
features of genetic drfit/characteristcis
random, due to chance and unpredictable
the founder effect
occurs when a small unrepresentative sample of individuals seperates from a larger populattion to colonise a new region and start a new population
effect of the flounder effect on new population
not representative of original population as only a small portion of alleles transfer
two major risks of low genetic diversity
inbreeding and lower adaptive potential
adaptive potential
ability for a population to adjust to new environmental selection pressures
bottleneck
the reduction in genetic diversity that occurs when a population suufers a large percentage loss of individuals
