The various Ensatina salamanders of the Pacific coast all descended from a common ancestral population ... A well-studied example of a ring species is the salamander Ensatina escholtzii of ...

The evidence is pieced together from details drawn from all over the world, but it adds up to a disturbing picture ... know that many more species are "living dead" -- populations so critically ...

U.S. bird populations are experiencing alarming declines due to factors such as habitat loss and climate change, according to ...

Butterfly populations have dropped by 22% in the United States, according to a new study published Thursday in the journal Science.

The world’s biodiversity is declining at an alarming rate. Population sizes of vertebrate species measured by the Living Planet Index (LPI) have more than halved in little more than 40 years. The LPI, ...

Many US Bird Species Seen as Reaching Population 'Tipping Point' By Will ... and egrets that show some increases," Parr added. Some examples of common birds now in decline include the chimney ...