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biology terms and defintions


change in a kind of organism over time


well tested explenation that unifies a broad range of observations


preserved remains or evidence of an efficient organism

natural varitaion

diffrences among individuals of a species

artificial selection

selection by human for breeding of useful traits

struggle for exsistence

completion among members of a species for food, living space, and other necesity of life


ability of an organism to survive and reproduce in its enviroment


inherited characteristic that increases an organisms chance of survival

survival of the fittest

process by which individuals that are better suited to their enviroment survive and reproduce

natural selection

process by which individuals that r better suited to their enviroment survive and reproduce mostly sucessful

descent with modification

principle that each living species has decended which change from another species over time

common decent

principle that all living things have a common ancestor

homologus structure

structures that have diffrent structure forms

vestgial organ

organ that serves no usefulo function in the organism

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