World's biggest snake gives climate clues

Skeletal remains from an enormous snake that would dwarf Hollywood's anacondas have been discovered near the equator, shedding new light on the climate and environment that housed the monstrous reptile 60 million years ago. "This colossal, boa constrictor-like creature stretched longer than a city bus and weighed more than a car. It's the biggest snake the world has ever known," says University of Toronto Mississauga paleontologist Jason Head, part of an international team that analyzed the remains. Their findings are published in the Feb. 5, 2009 edition of Nature.

The snake's giant vertebrate, found in Colombia, show it was far larger than any previously discovered, says Head, lead author on the paper. The giant reptile weighed more than 1.25 tons, was more than 13 metres long and had a body so wide it would have to squeeze through a doorway to enter a room. The snake ate giant turtles and crocodiles, whose skeletons were also uncovered.

Jonathan Bloch, a vertebrate paleontologist at the University of Florida's Florida Museum of Natural History, who co-led the expedition that discovered the snake with Carlos Jaramillo from the Smithsonian Tropical Research Institute, says the find provides scientists with a rare window into past equatorial environment.

"Until now, tropical South America's dense forest prevented discovery of fossil vertebrates found between 55 and 65 million years ago, so this discovery gives us a very unique and important glimpse into the past," he says.

Since the body size of snakes and other cold-blooded animals is determined by the temperature where they live, researchers used the snake's huge dimensions to paint a picture of what the equatorial climate was like 60 million years ago. Based on its size, scientists found the mean annual temperature at equatorial South America during that time would have been nearly 33 Celsius, about six degrees warmer than today.

"The key thing about this discovery is that we can use it as a launching point to develop very precise climatic reconstructions," says Head. "It will help us to look at how ecosystems respond to climate change and specifically, what happens when temperatures increase or decrease. Obviously, this type of knowledge is very relevant in today's changing climate."

Source: University of Toronto