Megafaunal Extinction During Ice Age Caused By Too Much Moisture, Study Suggests

Megafaunal animals during Ice Age across Eurasia and the Americas like mammoths and mastodons might have faced extinction by having too much moisture from the climate change. This is what the recent study suggests, adding more theories on how these animals went extinct.

In a study published in the Nature Ecology & Evolution titled "Megafaunal isotopes reveal role of increased moisture on rangeland during late Pleistocene extinctions," researchers from the Australian Centre for Ancient DNA (ACAD) at the University of Adelaide suggests that the persistent moisture from the melting permafrost and glaciers caused widespread glacial-age grasslands to be replaced by peatlands and bogs.

With this, it fragmented the population of megafaunal herbivore grazers. The study also revealed that the ancient bones preserve biochemical evidence of the environmental upheavals that could be traced through time, according to the University of Adelaide's official website

With the use of 511 radiocarbon-dated bones from megafaunal animals like bison, horse, and llamas, the research team investigated the role of environmental change in mysterious extinctions of large animals. This extinction that happened 11,000 to 15,000 years ago includes large land animals like saber-toothed cats, mastodons, and giant sloths.

"We didn't expect to find such clear signals of moisture increases occurring so widely across all of Europe, Siberia and the Americas," Alan Cooper, the leader of the study, said. Cooper, who also serves as the ACAD director, said the timing varied between regions but it sill matches the collapse of glaciers just before most megafaunal species extinct.

Lead author Tim Rabanus-Wallace of the University of Adelaide echoed Cooper's statement, adding that grassland megafauna was critical to the food chains back then, acting like the giant pumps that shifted nutrients around. "When the moisture influx pushed forests and tundras to replace the grasslands, the ecosystem collapsed and took many of the megafaunas with it," Rabanus-Wallace said.