← Chapter 24 Vocabulary Export Options Alphabetize Word-Def Delimiter Tab Comma Custom Def-Word Delimiter New Line Semicolon Custom Data Copy and paste the text below. It is read-only. Select All species a population of organisms that under natural conditions are able to mate and produce fertile offspring. macroevolution the evolution of new species. microevolution Evolutionary change below the species level; change in the allele frequencies in a population over generations.