Experts have detected alterations in Arctic bear DNA that might enable the creatures acclimatize to hotter environments. This study is considered to be the primary instance where a statistically significant connection has been found between increasing heat and changing DNA in a wild animal species.
Global warming is imperiling the future of Arctic bears. Estimates suggest that two-thirds of them might vanish by 2050 as their icy habitat disappears and the weather becomes warmer.
“The genome is the blueprint within every biological unit, guiding how an life form grows and develops,” said the principal investigator, Dr. Alice Godden. “By examining these bears’ expressed genes to regional environmental information, we observed that rising heat seem to be driving a significant increase in the activity of transposable elements within the specific area bears’ DNA.”
The team studied tissue samples taken from polar bears in separate zones of Greenland and compared “transposable elements”: tiny, movable pieces of the genetic code that can alter how other genes operate. The research examined these genetic markers in relation to temperatures and the related variations in genetic activity.
As regional weather and food sources change due to alterations in habitat and prey caused by climate change, the genetic makeup of the bears appear to be adjusting. The group of polar bears in the warmest part of the region displayed increased genetic shifts than the groups in colder regions.
“This finding is important because it demonstrates, for the initial occasion, that a unique group of polar bears in the warmest part of Greenland are employing ‘mobile genetic elements’ to rapidly modify their own DNA, which could be a desperate coping method against disappearing ice sheets,” noted Godden.
The climate in north-east Greenland are less variable and less variable, while in the southern zone there is a significantly hotter and more open water habitat, with steep climate variability.
DNA sequences in animals change over time, but this mechanism can be hastened by climate pressure such as a quickly warming planet.
The study noted some notable DNA alterations, such as in sections connected to lipid metabolism, that might aid Arctic bears cope when prey is unavailable. Animals in warmer regions had increased terrestrial food intake compared with the lipid-rich, marine nutrition of Arctic bears, and the DNA of south-eastern bears seemed to be adjusting to this change.
Godden elaborated: “We identified several active DNA areas where these jumping genes were very dynamic, with some located in the protein-coding regions of the genome, implying that the animals are undergoing rapid, significant DNA modifications as they respond to their melting Arctic home.”
The following stage will be to study additional subspecies, of which there are 20 globally, to see if comparable modifications are occurring to their DNA.
This research could aid protect the animals from extinction. However, the scientists emphasized that it was crucial to halt climate change from increasing by reducing the burning of carbon-based fuels.
“We must not relax, this presents some promise but does not mean that Arctic bears are at any reduced threat of disappearance. We still need to be undertaking every action we can to reduce global carbon emissions and decelerate climate change,” concluded Godden.
