Research Reveals Polar Bear DNA Changes May Help Adaptation to Climate Warming

Experts have identified alterations in polar bear DNA that may enable the creatures adjust to hotter climates. This study is thought to be the first instance where a statistically significant connection has been established between rising heat and changing DNA in a free-ranging animal species.

Climate Breakdown Threatens Polar Bear Future

Global warming is imperiling the future of polar bears. Forecasts show that two-thirds of them may vanish by 2050 as their snowy habitat retreats and the weather becomes warmer.

“DNA is the guidebook inside every biological unit, instructing how an creature grows and functions,” explained the lead researcher, Dr. Alice Godden. “Through analyzing these bears’ expressed genes to area climate data, we observed that rising temperatures appear to be driving a substantial increase in the behavior of transposable elements within the south-east Greenland bears’ DNA.”

Genetic Analysis Shows Key Changes

Researchers examined tissue samples taken from polar bears in separate zones of Greenland and evaluated “jumping genes”: tiny, movable sections of the genetic code that can affect how various genes work. The study focused on these genes in connection to temperatures and the associated variations in DNA function.

With environmental conditions and food sources change due to alterations in ecosystem and prey forced by climate change, the genetic makeup of the animals seem to be evolving. The community of polar bears in the hottest part of the area displayed more genetic shifts than the groups in colder regions.

Likely Adaptive Strategy

“This finding is significant because it demonstrates, for the first instance, that a particular group of polar bears in the warmest part of Greenland are utilizing ‘jumping genes’ to swiftly rewrite their own DNA, which may be a desperate coping method against retreating Arctic ice,” commented Godden.

Temperatures in the colder region are colder and less variable, while in the south-east there is a significantly hotter and more open water habitat, with steep climate variability.

Genomic information in species mutate over time, but this process can be sped up by environmental stress such as a rapidly heating environment.

Dietary Shifts and Active DNA Areas

Scientists observed some notable DNA changes, such as in areas associated to energy storage, that could assist Arctic bears persist when resources are limited. Animals in warmer regions had a greater proportion of fibrous, vegetarian diets compared with the blubber-focused diets of Arctic bears, and the DNA of these specific animals seemed to be evolving to this change.

Godden elaborated: “We identified several active DNA areas where these mobile elements were very dynamic, with some found in the critical areas of the genome, suggesting that the animals are experiencing rapid, profound evolutionary shifts as they adjust to their vanishing sea ice habitat.”

Next Steps and Broader Impact

The subsequent phase will be to look at different Arctic bear groups, of which there are 20 worldwide, to determine if comparable changes are taking place to their DNA.

This study may help safeguard the animals from dying out. However, the experts emphasized that it was vital to stop climate change from increasing by reducing the use of coal, oil, and gas.

“We must not relax, this presents some optimism but is not a sign that Arctic bears are at any less risk of disappearance. It remains crucial to be undertaking everything we can to reduce global carbon emissions and mitigate climate change,” concluded Godden.