Given the diversity of social taxa, why do some species form complex societies, while other closely related species do not? Within these societies, why do some individuals attempt to reproduce ...

The brains of birds and mammals have diverged substantially during the course of evolution. A research team at the Center for Molecular Biology of Heidelberg University has investigated how similar ...

They are as distinct as though they were two separate species. Yet the entire complex of populations belongs to a single taxonomic species, Ensatina escholtzii. Ring species, says biologist David ...