23 Mar 2012:
Australian Mammal Extinctions
Tied to Human Hunting, Not Climate Change
The disappearance roughly 40,000 years ago of dozens of large mammals in Australia — including rhinoceros-sized wombats and tapir-like marsupials — was caused by human hunting and not by climate change
, according to a new study by Australian scientists. Researchers at the University of
©Science/AAAS/Drawing by Peter Murray
Tasmania reached that conclusion after analyzing two mud core samples dating back as far as 130,000 years. By examining the cores for the Sporomiella
fungus — which only releases its spores when in the dung of plant-eating animals — the scientists concluded that megafauna survived periods of climate change over the last 100,000 years. But when humans arrived in sizeable numbers, the presence of the spores dropped “almost to zero” around 41,000 years ago, indicating that hunting was the main reason for the extinction of these large animals, according to the paper, published in Science
. Not long after the megafauna was hunted to extinction, grasses and trees began to grow more profusely because of the decline of grazing animals, setting the stage for large fires. The Australian research parallels other, similar findings worldwide showing that human hunting was crucial in large-animal extinctions.
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
Yale Environment 360
articles are now available in Spanish and Portuguese on Universia
, the online educational network. Visit the site.
Business & Innovation
Policy & Politics
Pollution & Health
Science & Technology
Antarctica and the Arctic
Central & South America
Photographer Robert Wintner documents the exquisite beauty and biodiversity of Cuba’s coral reefs, which are largely intact thanks to stifled coastal development in the communist nation. View the gallery.
is now available for mobile devices at e360.yale.edu/mobile
The Warriors of Qiugang
, a Yale Environment 360
video, chronicles a Chinese village’s fight against a polluting chemical plant. It was nominated for a 2011 Academy Award for Best Documentary Short.
Watch the video.
Top Image: aerial view of Iceland
. © Google & TerraMetrics.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.