Polar bears are leaping through their evolution in real time as rising temperatures threaten their habitat. A population of the majestic white carnivores found in an uncharacteristically temperate climate showed genetic differences from their colder-weather counterparts. And those differences could be key to the survival of the species, as well as show how other animals and humans could evolve in the future.
The isolated colony of polar bears found in southeast Greenland “inhabits a warmer climate zone, akin to the predicted future environments of polar bears with vastly reduced sea ice habitats,” said a study published in the journal Mobile DNA. The subpopulation is particularly interesting as it may have had a “200-year start on developing advantageous genetic changes for survival in this shifting landscape,” said Popular Mechanics.
This difference can be attributed to “jumping genes,” or transposons, which are “mobile pieces of a gene that can move around to influence how other genes work,” said Popular Mechanics.
Jumping genes are like “puzzle pieces that can rearrange themselves, sometimes helping animals adapt to new environments,” said Alice Godden, a co-author of the study.
In this case, Godden said in The Conversation, her team found “active jumping genes in parts of the genome that are involved in areas tied to fat processing,” which is “important when food is scarce.” The polar bear genome comprises about 38.1% jumping genes, compared to 45% in humans. Scientists believe this is the “first documented case of rising temperatures driving genetic change in a mammal,” said NBC News. |