Rising temperatures in Australia have caused birds on that continent to shrink--some by nearly 4 percent. The findings of a study published in the journal Proceedings of the Royal Society B are the first to show that birds' sizes are affected by global warming, although this phenomenon previously has been shown in fish and Soay sheep. Scientists postulate that the relationship between a warmer climate and smaller animals may be true for the animal kingdom as a whole. Temperature has a clear impact on body size; it's old news among scientists that birds closer to the equator evolved to be smaller than their peers near the poles. One possible explanation for this,
called Bergmann's Rule, is that larger animals conserve heat more efficiently, and this trait is naturally selected for in colder climates, but not in warmer climates. On this basis, scientists have predicted that climate change will affect the ...
