SYDNEY – Tasmanian devils have become more resistant to a facial tumor that has decimated their population in recent decades in Australia, raising hopes of them being able to survive the cancer, according to a study released on Thursday.
An investigation by researchers from Australia and France found that the marsupials (Sarcophilus harrisii) have shown signs of evolutionary adaptations and phenotypic plasticity, meaning a change in characteristics of an organism in response to environmental surroundings.
“All the evidence suggests that devils have the capacity to adapt to this transmissible cancer at genetic and phenotypic levels,” said study’s co-author Rodrigo Hamede in a statement by the University of Tasmania.
“We have been observing natural selection in action, and this has happened in a very short amount of time,” he said, adding that until a few years ago, Tasmanian devils faced a serious risk of extinction from tumor.
The results confirmed previous studies that revealed a lower degree of infection in specimens with elevated levels of certain types of immune molecules, as well as an ability to adapt in its immune system to fight this disease.
“Active immune responses to DFTD (deadly devil facial tumour disease) and even tumour regression have recently been observed in several animals,” said another researcher, Beata Ujvari.
She added that immune signatures in Tasmanian devils could be used for genetic management of insurance populations and assisting research aimed at developing a vaccine.
Another researcher, Tracey Russell, underlined that Tasmanian devils have multiple mates and choose the best partner for reproduction, which helps maintain genetic diversity and enhances the potential to respond to the cancer.
The tumor affecting Tasmanian devils, which is often contracted through wounds sustained in fights with other infected specimens, appears in the mouth and grows in size until it causes deformities that make eating difficult.
The Tasmanian devil was once widespread in Australia, but currently it is restricted to the island of Tasmania where its survival is threatened by the facial tumor disease and low genetic diversity.