Using a new population modelling approach, the study contradicts the widespread belief that disease must have been a factor in the thylacine’s extinction.
The thylacine was a unique marsupial carnivore found throughout most of Tasmania before European settlement in 1803. Between 1886 and 1909, the Tasmanian government encouraged people to hunt thylacines and paid bounties on over 2000 thylacine carcasses. Only a handful of animals were located after the bounty was lifted and the last known thylacine was captured from the wild in 1933.
“Many people, however, believe that bounty hunting alone could not have driven the thylacine extinct and therefore claim that an unknown disease epidemic must have been responsible,” says the project leader, Research Associate Dr Thomas Prowse, School of Earth and Environmental Sciences and the Environment Institute.
“We tested this claim by developing a ‘metamodel’ – a network of linked species models – that evaluated whether the combined impacts of Europeans could have exterminated the thylacine, without any disease.”
The mathematical models used by conservation biologists to simulate the fate of threatened species under different management strategies (called population viability analysis or PVA) traditionally neglect important interactions between species. The researchers designed a new approach to PVA that included species interactions.
“The new model simulated the directs effects of bounty hunting and habitat loss and, importantly, also considered the indirect effects of a reduction in the thylacine’s prey (kangaroos and wallabies) due to human harvesting and competition from millions of introduced sheep,” Dr Prowse says.
“We found we could simulate the thylacine extinction, including the observed rapid population crash after 1905, without the need to invoke a mystery disease.
“We showed that the negative impacts of European settlement were powerful enough that, even without any disease epidemic, the species couldn’t escape extinction.”
The study ‘No need for disease: testing extinction hypotheses for the thylacine using multi-species metamodels’, which also involved Professors Corey Bradshaw and Barry Brook from the University of Adelaide’s Environment Institute, Professor Chris Johnson from the University of Tasmania, and Dr Bob Lacy, Chicago Zoological Society, has been published online in the Journal of Animal Ecology.1) Dr Thomas Prowse
The oceans can’t take any more
03.07.2015 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
Improved veterinary service for livestock is significant for leopard conservation
02.07.2015 | Georg-August-Universität Göttingen
When a duck paddles across a pond or a supersonic plane flies through the sky, it leaves a wake in its path. Wakes occur whenever something is traveling...
Researchers explore ultrafast control of magnetism across interfaces: A new study discovers how the sudden excitation of lattice vibrations in a crystal can trigger a change of the magnetic properties of an atomically-thin layer that lies on its surface.
A research team, led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter at CFEL in Hamburg, the University of Oxford, and the...
Wind turbines could be installed under some of the biggest bridges on the road network to produce electricity. So it is confirmed by calculations carried out by a European researchers team, that have taken a viaduct in the Canary Islands as a reference. This concept could be applied in heavily built-up territories or natural areas with new constructions limitations.
The Juncal Viaduct, in Gran Canaria, has served as a reference for Spanish and British researchers to verify that the wind blowing between the pillars on this...
New technique combines electron microscopy and synchrotron X-rays to track chemical reactions under real operating conditions
A new technique pioneered at the U.S. Department of Energy's Brookhaven National Laboratory reveals atomic-scale changes during catalytic reactions in real...
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and a half billion years ago.
Think of an object made of iron: An I-beam, a car frame, a nail. Now imagine that half of the iron in that object owes its existence to bacteria living two and...
25.06.2015 | Event News
16.06.2015 | Event News
11.06.2015 | Event News
07.07.2015 | Physics and Astronomy
07.07.2015 | Earth Sciences
07.07.2015 | Physics and Astronomy