One of the most intriguing and intricate mysteries in paleontology is the disappearance of North America's giant mammals, or megafauna, which included saber-toothed cats, mastodons, and mammoths, some ...

Extinction rates appear to have slowed since their peak in the early 1900s, suggesting not a reprieve for nature but a shift in how and where losses occur. Much of the damage was concentrated on ...

(CNN) — Humans have wiped out more than 100 species — with many more on the brink or experiencing large declines in population. Some scientists have argued that we have entered a “sixth mass ...