Did Humans Cause Ecosystem Collapse in Ancient Australia?

Massive extinctions of animals and the arrival of the first humans in ancient Australia may be linked, according to scientists at the Carnegie Institution, University of Colorado, Australian National University, and Bates College. The extinctions occurred 45,000 to 55,000 years ago. The researchers traced evidence of diet and the environment contained in ancient eggshells and wombat teeth over the last 140,000 years to reconstruct what happened. The remains showed evidence of a rapid change of diet at the time of the extinctions.