Global warming too hot for Tuatara
Sydney Daily Telgraph 5/6/2007
WELLINGTON: It has survived ica ages, volcanic eruptions and the intrusion of humans, but New Zealand's last survivor of the dinosaur may not survive global warming.
Covered in spiny scales and rough, grey camouflage skin, the tuatara is one of the wolrd's oldest living creatures. But the lizard-like-reptile is facing extinction from global warming because of its dependency on ambient temperature which determines the sex of young while still in the egg.
"They've survived climate change in the past but most of those [past climate changes] had been slower,"Victoria University researcher Jennifer Moore said.
The sex of the tuatara-the only survivor of its species of reptile since the age of dinosaurs-depends on the temperature of the soil where the eggs are laid.
A cooler temperature produces females, while a warmer soil temperature results in male offspring. It can grow up to 50cm and weigh up to 1kg and like its relative, the turtle, the slow-moving tuatara can live more than 100 years, feeding mainly on insects.
But scientists say its long life span as well as its four-year breeding cycle-relatively slow for a reptile-will make the adaptation process more difficult.
A temperature above 21.5C creates more male tuatara while a cooler climate leads to females-with males already outnumbering females by two-to-one.
javajimi: Maybe we should start to show on tv how many creatures of this planet are already at risk from the heating up of the planet, regardless of if we believe it will affect us.
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