1095ac85_Materials___USU_OpenCourseWare__2
[1] r. [2] 
change in the frequency of biological traits in a species that results from the fact that, in a given environment, the characteristics of different individual members of a species give some individuals a better chance of surviving and therefore passing on those helpful traits to the next generation
Chapter 3: Biology and Culture — Free Online Course Materials — USU OpenCourseWare
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