Researchers have detected alterations in polar bear DNA that may assist the animals acclimatize to increasingly warm environments. This study is thought to be the primary instance where a notable link has been established between increasing heat and changing DNA in a wild animal species.
Climate Breakdown Puts at Risk Polar Bear Existence
Climate breakdown is imperiling the future of polar bears. Projections indicate that a large portion of them may disappear by 2050 as their frozen habitat melts and the climate becomes hotter.
“The genome is the blueprint inside every cell, guiding how an creature grows and develops,” stated the principal investigator, Dr. Alice Godden. “By examining these bears’ functioning genes to local environmental information, we found that increasing temperatures appear to be driving a significant surge in the function of jumping genes within the warmer Greenland region bears’ DNA.”
DNA Study Shows Key Modifications
The team studied biological samples taken from Arctic bears in two regions of Greenland and evaluated “transposable elements”: tiny, roving sections of the genetic code that can affect how other genes function. The study examined these genes in correlation to climate conditions and the corresponding variations in gene expression.
As regional weather and nutrition evolve due to alterations in ecosystem and prey forced by warming, the genetic makeup of the bears appear to be evolving. The group of bears in the warmest part of the region displayed increased genetic shifts than the populations in colder regions.
Possible Evolutionary Response
“This result is important because it demonstrates, for the initial occasion, that a particular population of polar bears in the hottest part of Greenland are employing ‘mobile genetic elements’ to swiftly rewrite their own DNA, which may be a desperate survival mechanism against retreating ice sheets,” added Godden.
Temperatures in north-east Greenland are more frigid and more stable, while in the southern zone there is a much warmer and more open water environment, with steep climate variability.
Genetic code in animals mutate over time, but this mechanism can be sped up by external pressure such as a quickly warming planet.
Food Source Variations and Key Genomic Regions
The study noted some interesting DNA alterations, such as in areas linked to energy storage, that might help Arctic bears persist when food is scarce. Animals in hotter areas had increased terrestrial food intake compared with the blubber-focused nutrition of northern bears, and the DNA of south-eastern bears seemed to be evolving to this new reality.
Godden stated: “Scientists found several genetic hotspots where these jumping genes were very dynamic, with some found in the critical areas of the DNA, implying that the animals are experiencing swift, profound DNA modifications as they adapt to their vanishing sea ice habitat.”
Further Study and Broader Impact
The next step will be to look at additional Arctic bear groups, of which there are twenty around the world, to determine if similar changes are taking place to their DNA.
This study could help safeguard the animals from extinction. However, the researchers stressed that it was crucial to stop temperature rises from escalating by cutting the burning of coal, oil, and gas.
“We must not relax, this provides some optimism but does not mean that Arctic bears are at any reduced threat of disappearance. It remains crucial to be pursuing everything we can to lower global carbon emissions and mitigate global warming,” stated Godden.
