WASHINGTON — Global warming and evolution are reshaping the bodies of some American bumblebees, a new study finds.
The tongues of two Rocky Mountains species of bumblebees are about one-quarter shorter than they were 40 years ago, evolving that way because climate change altered the buffet of wildflowers they normally feed from, according to a study published Thursday in the journal Science.
In one of these species, the tongue had been half the size of the bee’s body — the equivalent of a human tongue going down to the waist.
But because the flowers where the long tongue is required have dwindled, the bees didn’t need that much tongue.
Keeping long tongues requires bees use more energy, so the bees evolved a shorter tongue that allows them to sample a wider variety of flowers.
Scientists worry that without long-tongued bees, some flowers will falter. Also, shorter-tongue bees often “cheat” and bite a hole in the flower’s side, which doesn’t help the plant spread its seeds.
