Climate and Size

Animals that live in cold [climates:weather] tend to have stubby limbs - shorter arms and legs - even smaller ears and tails. Picture a penguin and you'll see what I mean. [Biologists:Researchers] have long assumed that these stumpy appendages are an evolutionary adaptation. Shorter [extremities:intensity] minimize heat loss, so animals that are more compact are better suited to the cold.But scientists from Ohio say that temperature may have a more direct effect on the length of an animal's limbs. Because they find that turning up the heat helps [cartilage:heat] grow - results that were published in the Proceedings of the National Academy of Sciences.The researchers raised mice at several different temperatures, and they [confirmed:assured] that those kept at a balmy 80 degrees were longer limbed than those who lived at a more chill 45. But how does a little heat make mice more leggy? The answer, they find, lies in the cartilage. Long bones grow from the cartilage found at either end. And the warmer it is, the more that cartilage grows, even when it's just sitting in a test tube. Which I guess means it's [possible:definite] that the dog days of summer lead to [longer-legged:shorter] dogs.