Climate change may have helped drive Australia’s marsupial tigers into a permanent grave, along with their dodgy feet.
The last of the marsupial tigers that once roamed mainland Australia – the Tasmanian Tiger – died out 90 years ago. Aussie researchers believe they now know what drove a once-diverse group of species called thylacines to extinction: a rapidly-cooling climate about 14 million years ago.
They found thylacines declined during this period, when global temperatures suddenly dropped by about seven degrees Celsius.
The cooler climate transformed Australia’s wet, closed forests into dry, open woodlands, and that’s where the tigers’ dodgy feet come in.
“We think the structure of tigers’ feet and ankles might have made them better suited to closed forests with uneven surfaces, such as roots and logs, and less well suited to open woodlands,” says PhD scholar Shimona Kealy, from the Australian National University.
The same time period also saw the rise of modern carnivorous marsupials such as the Tasmanian Devil and cat-sized quolls, known as dasyurids.
Researchers say the rise of dasyurids appears to have something to do with their superior ear-bone structure, which was better adapted to open woodland environments and allowed them to hear over greater distances than thylacines.
The study relied on an analysis of 95 modern and fossil species, including six species of tigers, studying their skulls, teeth and jaws, along with molecular gene sequences.
The research has been published in the journal BMC Evolutionary Biology.