Forces of Evolution Flashcards
two major developments of understanding evolutionary synthesis
mendels theory of heredity
darwins theory of evolution
mendels theory of heredity
discrete units of information (genes) are passed unchanged from generation to generation
modern synthesis of evolution
- it is the production and redistribution of variation (inherited differences among organisms)
- natural selection acts on this variation causing inherited differences among individuals to affect their ability to successfully reproduce
current definition of evolution
a change in allele frequency from one generation to he next
allele frequencies are indicators of…
the genetic makeup of a population, the members of which share a common gene pool
allele frequences refer to the…
percentage of all the alleles at a locus accounted for by one specific allele
microevolution
small genetic changes that occur within a species, even just from one generation to the next
example of microevolution in humans
different ABO blood types
macroevolution
large scale changes that occur in populations after many generations, such as the appearance of a new species
speciation
appearance of a new species
5 factors that produce and redistribute variation, allowing for evolution
mutation gene flow genetic drift and founder effect recombination natural selection
mutation
molecular alteration in genetic material
for a mutation to have evolutionary significance it must occur in a
gamete
mutation rates for any given trait are usually
low
what is the only way to produce new genes
mutation
if mutation offers an advantage or disadvantage, when combined with natural selection evolutionary changes can occur
more and more rapidly
gene flow
the exchange of genes between populations
gene flow is a consistant feature of
human evolution
human examples of gene flow
offspring of US soldiers and vietnamese women
when individuals move temporarily and mate in a new population they dont necessarily
stay there
flow of genes is characterized by
gradual distribution
exogamous
individuals marry outside of some cultural/ genetic group
endogamous
individuals marry inside of some cultural/genetic group
exagamous relationships result in…
higher genetic diversity, more gene flow