ananyo writes "Large-brained animals may be less likely to go extinct in a changing world, perhaps because they can use their greater intelligence to adapt their behavior to new conditions, according to an analysis presented to a meeting of conservation biologists this week. 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. The researchers 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'. 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. For species larger than about 10 kilograms, the advantage of having a large brain seems to be swamped by the disadvantage of being big — such as attracting the unwelcome attention of humans."