A new fossil and DNA analysis traces how dozens of sloth species responded to climate shifts and humans. Just two small tree-dwelling sloths remain today.

It’s forcing the human race into what evolutionary biologists call a “bottleneck” — a period of rapid pressure that threatens cultures, customs and peoples with extinction. When college ...

For decades, most paleontologists blamed the climate for the disappearance of North America’s megafauna. Their extinction coincided with the end of the last ice age, a time when the planet ...

Scientists have long debated why woolly mammoths, giant sloths and 44 more giant, plant-eating 'megaherbivores' went extinct starting around 50,000 years ago. Some paleontologists, biologists and ...

They had remained in cold storage until paleogeneticists at the McMaster Ancient DNA Centre applied new genomics techniques to better understand the global extinction of megafauna that had ...

The findings challenge previous assumptions about the causes of megafaunal extinctions in Africa and provide new insights into the restructuring of ecosystems over millions of years. Faysal Bibi ...

The new study indicates the ancestral population began to grow at the peak of the island’s megafaunal mass extinction. Archaeological evidence also suggests that as their numbers grew ...

Smithsonian scientist’s research illustrates how North American ecosystems are still reeling from the megafaunal extinction that closed the ice ages Jack Tamisiea During the late Pleistocene ...

Now a study has found that the continents that lost the most of these grazing megafauna had the biggest ... with lower increases where there were fewer extinctions, such as in Africa.