Climate Change May Cause Reptile To Change Sex, NZ
July 2, 2008
Prehistoric Tuatara reptiles in New Zealand may become extinct because all their females will be gone. A recent study says that in higher temperatures all the new born creatures will be male, and the authors of Australian research suggest organising artificial shadowed areas above the Tuatara nests.
Scientists from Melbourne University have published a study which claims the Tuatara will hardly ever be able to change its natural habitat and migrate to colder places if Earth’s average temperature is 4 degrees Celsius warmer, as predicted under climate change.
The sex of the Tuatara depends on the temperature in which embryos develop. When it’s 22.1 degrees Celsius or lower a female animal will be born, but at 22.2 degrees or higher all the new-borns will be male.
Tuatara has been preserved since Jurassic times, as it is as old as 200 million years. It has preserved some features of reptiles, for example the so-called ‘third eye’ – a visual (photosensitive) organ on the crown of its head. Their metabolism is extremely slow, and they live for 100 years on average, but in the same time have a very high rate of genetic evolution.
They live in burrows, eat insects and baby birds. Some animals brought by colonists that hadn’t naturally inhabited New Zealand have considerably decreased the number of Tuatara.
So, the ancient animal who has survived through tens of millions of years may vanish due to global warming in the 21th century, and as the alarming news come in, it’s hard to say which species will be the next target of the climate change – some reptiles, birds or even primates, including humans.