A new study has found that global warming and evolution have been reshaping the bodies of some American bumblebees. According to a study published on Thursday in the journal Science, the tongues of two Rocky Mountains species of bumblebees were nearly one-quarter shorter as compared to what they were 40 years back.

They have evolved in this way because climate change has changed the buffet of wildflowers they usually feed from.

The tongue of one of these species had been half the size of the bee's body, which is equal to a human tongue going down to the waist. As the flowers where the long tongue is needed have is required have diminished thus the bees didn't require that long tongue now.

Study lead author Nicole Miller-Struttmann at the State University of New York, Old Westbury, said when bees have long tongues they use more energy, thus they have evolved a shorter tongue, allowing them to sample huge number of flowers.

Study co-author Candace Galen at the University of Missouri, said that biologists have already found how global warming has changed the developmental, migration, timing and other behavior in plants and animals, but what has made this study different is the physical changes in the bees.

Galen said, “It speaks to the magnitude of the change of the climate that it's affecting the evolution of the organisms. It's a beautiful demonstration of adaptive evolution”.

Like their relatives the honeybees, bumblebees feed on nectar, using their long hairy tongues to lap up the liquid; the proboscis is folded under the head during flight. Bumblebees gather nectar to add to the stores in the nest, and pollen to feed their young.

"The pattern seen here may predict future effects of climate change in other systems," the researchers said.

"The silver lining is that (the bees) are evolving very quickly," Miller-Struttmann said. "The story may not be as rosy for the flowers."