A new scientific paper finds that warm-blooded animals are evolving larger beaks, legs, ears and tails, as they try to adapt to a warmer planet.
"Appendages have an important, but often undervalued, role in animal thermoregulation", as the authors write — in birds, for example, beaks are used to expel heat. If a species of bird is persistently overheated, then over several generations it'll gradually evolve larger beaks. Same goes for some tails and legs and ears in other animals.
Global warming is thus driving animals to "shapeshifting", as the Guardian reports …
Examples include several species of Australian parrot that have shown a 4-10% increase in bill size since 1871, positively correlated with the summer temperature each year.
Meanwhile, research on the North American dark-eyed juncos, a type of small songbird, showed a link between increased bill size and short-term temperature extremes in cold environments.
Researchers have also reported tail length increases in wood mice, and tail and leg size increases in masked shrews. Bats in warm climates were shown to have increased wing size.