Local adaptation has been a major focus of evolutionary ecologists working across diverse
systems for decades. However, little of this research has explored variation at …

The importance of hybridization in plant speciation and evolution has been debated for
decades, with opposing views of hybridization as either a creative evolutionary force or …

In recent years, scientists have realized that evolution can occur on timescales much shorter
than the" long lapse of ages" emphasized by Darwin—in fact, evolutionary change is …

I consider how the study of genetic variation has influenced efforts to conserve natural
populations over the last 50 years. Studies with allozymes in the 1970s provided the first …

The species problem has triggered the publication of an almost infinite number of theoretical
and practical studies, including quite a number of books. I should, therefore, perhaps briefly …

No one in this century can speak with greater authority on the progress of ideas in biology
than Ernst Mayr. And no book has ever established the life sciences so firmly in the …

There is abundant geographic variation in both morphology and gene frequency in most
species. The extent of geographic variation results from a balance of forces tending to …

The second edition was a hasty one, prepared in hospital only with the help of amendations
on typed slips. The present revision has been more thorough, so that contents and …

This balanced, comprehensive account traces the alterations in body form that insects
undergo as they adapt to seasonal change, exploring both theoretical aspects and practical …

Plant populations are not randomly arranged assemblages of genotypes but are structured
in space and time (2, 29, 49, 58, 84, 112). This structure may be manifested among …