Evolution | Microevolution | Macroevolution | Genetic drift | Natural selection

Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes that are passed on from parent to offspring during reproduction. Genetic drift is the change in the frequency of an existing gene variant in a population due to random chance. Genetic drift may cause gene variants to disappear completely and thereby reduce genetic variation. It can also cause initially rare alleles to become much more frequent and even fixed. Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. #evolution #Darwin #CharlesDarwin #WhatIsEvolution #RichardDawkins #Creationism #InteligentDesign #NaturalSelection #Genetics #DNA #NikolaysGeneticsLessons #science #theory #biology #crashcourse #gene #Facts #fossil #fossilRecord #dinosaur #extinct #extinction #organism #dorudon #rodhocetus #vestigial #structure #similarity #homologousStructure #related #relationship #morganucodon #RNA #chimpanzee #FruitFly #biogeography #resistance #selectivePressure #italianWallLizard