A team of researchers recently used modern technology to study the brains of thylacines, also called Tasmanian tigers. Little is known about the now-extinct animals but the study revealed some details, including evidence that the thylacine was an intelligent predator and not a scavenger. The findings were just published in the journal PLOS ONE.
The thylacine (Thylacinus cynocephalus) was an Australian marsupial, the same pouched group that includes kangaroos and koalas. Better known as Tasmanian tigers or Tasmanian wolves, they were dog-like in appearance and had striped backs. They were believed to be closely related to Tasmanian devils and numbats. Thylacines evolved 4 million years ago and still existed in the wild during the early colonization of Australia. Their numbers quickly dropped due to the introduction of dogs and dingoes combined with active hunting by humans. Humans are generally blamed for the eventual extinction of the species. The last captive thylacine died in 1936 at the Hobart Zoo. Since then, occasional sighting reports have popped up but scientists have never found any evidence of living thylacines. Very little is known about their ecology and behavior.
Scientists from Emory University and the University of New South Wales collaborated to attempt something that had never been done—using brain scans to study the anatomy of an extinct animal. The team used both magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) to study the brains of two preserved thylacine bodies. The brains were over 100 years old and the researchers weren’t sure how much information they’d be able to gather.
The team found that the thylacine brain was larger and more complex than that of its relative, the Tasmanian devil. Based on data from the brain scans, the researchers also determined that the thylacine had a predatory brain. Compared to similar animals, the thylacine brain had more cortex space devoted to tasks such as planning and decision-making. This shows that the thylacine was likely an intelligent, predatory animal and not a simple scavenger. The researchers included these brain scans in their new public project, Brain Ark.
The authors have now been able to prove that modern brain scan techniques can be used to study the brains of extinct animals. Their study provided new insights into the thylacine brain and showed that the animals were predators, with different behavioral patterns than their Tasmanian devil relatives. The team has also released a database called Brain Ark, which provides data on the brain structures of different animals. The Brain Ark archive is completely public and available to researchers. So far, it includes information on dolphins, Tasmanian devils, and thylacines. The team hopes that it will become an invaluable resource as more brain scans are added.
Berns GS, Ashwell KWS. Reconstruction of the Cortical Maps of the Tasmanian Tiger and Comparison to the Tasmanian Devil. PLOS ONE (2017).