New study suggests that being smarter is a defense against extinction
|July 18, 2012||Posted by News under extinction, News|
In “Mostly the Big-Brained Survive” (Scientific American, July 17, 2012), Emma Marris and Nature magazine report, “Animals’ brain-to-body size ratio predicts their likelihood of extinction, a new analysis finds”:
Brain size relative to body size is fairly predictable across all mammals, says Eric Abelson, who studies biological sciences at Stanford University in Palo Alto, California. “As body size grows, brain size grows too, but at slower rate,” he says. Plotting brain size against body size creates a tidy curve. But some species have bigger or smaller brains than the curve would predict for their body size. And a bigger brain-to-body-size ratio usually means a smarter animal.
Abelson looked at the sizes of such deviations from the curve and their relationships to the fates of two groups of mammalian species — ‘palaeo’ and ‘modern’. The palaeo group contained 229 species in the order Carnivora from the last 40 million years, about half of which are already extinct. The modern group contained 147 species of North American mammals across 6 orders. Analysis of each group produced similar results: species that weighed less than 10 kilograms and had big brains for their body size were less likely to have gone extinct or be placed on the International Union for Conservation of Nature red list for endangered species.
Perhaps this information might help predict the ability of a life form to adapt to an urban environment.