When two organisms typically do not interbreed with one another, they are considered different species. But what are the reproductive barriers that isolate one population from another? Hear the ...

A rare example of gene incompatibility between two species of budding yeast has been found. This discovery of elusive 'speciation' genes adds to other reproductive-isolation mechanisms operating in ...

Experiments were designed to clarify the role of olfactory stimuli in sexual isolation between the closely related and allopatric mice, Peromyscus maniculatus rufinus and P. polionotus leucocephalus.

The American Biology Teacher, a nationally recognized journal, offers articles on recent advances in biology and life science, instructional activities for the classroom and laboratory, and ...