{"id":190043,"date":"2025-12-17T21:10:11","date_gmt":"2025-12-17T21:10:11","guid":{"rendered":"https:\/\/www.newsbeep.com\/il\/190043\/"},"modified":"2025-12-17T21:10:11","modified_gmt":"2025-12-17T21:10:11","slug":"polar-bears-may-be-evolving-to-survive-in-a-warmer-world-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/il\/190043\/","title":{"rendered":"Polar Bears May Be Evolving to Survive in a Warmer World : ScienceAlert"},"content":{"rendered":"<p>The Arctic Ocean current is at its warmest in the last 125,000 years, and temperatures continue to rise. Due to these warming temperatures, more than two-thirds of polar bears are expected to be extinct by 2050, with total extinction predicted by the end of this century.<\/p>\n<p>But in our <a href=\"https:\/\/link.springer.com\/article\/10.1186\/s13100-025-00387-4\" rel=\"nofollow noopener\" target=\"_blank\">new study<\/a>, my colleagues and I found that the changing climate was driving changes in the polar bear genome, potentially allowing them to more readily adapt to <a href=\"https:\/\/researchprofiles.ku.dk\/en\/publications\/arctic-climate-and-climate-change-with-a-focus-on-greenland\/\" rel=\"nofollow noopener\" target=\"_blank\">warmer habitats<\/a>.<\/p>\n<p>Provided these <a href=\"https:\/\/theconversation.com\/uk\/search?q=polar+bears\" rel=\"nofollow noopener\" target=\"_blank\">polar bears<\/a> can source enough food and breeding partners, this suggests they may potentially survive these new challenging climates.<\/p>\n<p>Related: <a href=\"https:\/\/www.sciencealert.com\/stunning-award-winning-photo-of-vulnerable-polar-bear-stirs-the-heart\" rel=\"nofollow noopener\" target=\"_blank\">Stunning Award-Winning Photo of Vulnerable Polar Bear Stirs The Heart<\/a><\/p>\n<p>We discovered a strong link between rising temperatures in south-east Greenland and changes in polar bear DNA.<\/p>\n<p>DNA is the instruction book inside every cell, guiding how an organism grows and develops. In processes called <a href=\"https:\/\/www.ncbi.nlm.nih.gov\/books\/NBK26887\/\" rel=\"nofollow noopener\" target=\"_blank\">transcription and translation<\/a>, DNA is copied to generate RNA (molecules that reflect gene activity) and can lead to the production of proteins, and copies of transposons (TEs), also known as &#8220;jumping genes&#8221;, which are mobile pieces of the genome that can move around and influence how other <a href=\"https:\/\/www.nature.com\/scitable\/topicpage\/transposons-the-jumping-genes-518\/\" rel=\"nofollow noopener\" target=\"_blank\">genes work<\/a>.<\/p>\n<p>In carrying out our recent research, we found that there were big differences in the temperatures observed in the north-east, compared with the south-east regions of Greenland.<\/p>\n<p>Our team used publicly available polar bear genetic data from a research group at the <a href=\"https:\/\/www.science.org\/doi\/10.1126\/science.abk2793\" rel=\"nofollow noopener\" target=\"_blank\">University of Washington, US,<\/a> to support our study. This dataset was generated from blood samples collected from polar bears in both northern and south-eastern Greenland.<\/p>\n<p>Our work built on the <a href=\"https:\/\/fish.uw.edu\/faculty\/kristin-laidre\/\" rel=\"nofollow noopener\" target=\"_blank\">Washington University study<\/a>, which discovered that this south-eastern population of Greenland polar bears was genetically different from the north-eastern population. South-east bears had migrated from the north and became isolated and separate approximately 200 years ago, <a href=\"https:\/\/www.science.org\/doi\/10.1126\/science.abk2793\" rel=\"nofollow noopener\" target=\"_blank\">it found<\/a>.<\/p>\n<p>Researchers from Washington had extracted RNA from polar bear blood samples and sequenced it. We used this RNA sequencing to look at RNA expression \u2013 the molecules that act like messengers, showing which genes are active, in relation to the climate.<\/p>\n<p>This gave us a detailed picture of gene activity, including the behaviour of TEs. Temperatures in Greenland have been closely monitored and recorded by the <a href=\"https:\/\/www.dmi.dk\/vejrarkiv\" rel=\"nofollow noopener\" target=\"_blank\">Danish Meteorological Institute<\/a>. So we linked this climate data with the RNA data to explore how environmental changes may be influencing polar bear biology.<\/p>\n<p>Does temperature change anything?<\/p>\n<p>From our analysis, we found that temperatures in the north-east of Greenland were colder and less variable, while south-east temperatures fluctuated and were significantly warmer.<\/p>\n<p>The figure below shows our data as well as how temperature varies across Greenland, with warmer and more volatile conditions in the south-east. This creates many challenges and changes to the habitats for the polar bears living in these regions.<\/p>\n<p><a href=\"https:\/\/images.theconversation.com\/files\/703439\/original\/file-20251119-66-ktv873.png?ixlib=rb-4.1.0&amp;q=45&amp;auto=format&amp;w=1000&amp;fit=clip\" rel=\"nofollow noopener\" target=\"_blank\"><img decoding=\"async\" alt=\"A map of Greenland indicating the location of the polar bears sampled in the north and south-east of Greenland, coupled with the temperature of those locations. The temperatures were more varied and overall much warmer in the south-east\" src=\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2025\/12\/file-20251119-66-ktv873.png\"   loading=\"lazy\"\/><\/a>Author data visualisation using temperature data from the Danish Meteorological Institute. Locations of bears in south-east (red icons) and north-east (blue icons). (<a href=\"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/\" rel=\"nofollow noopener\" target=\"_blank\">CC BY-NC-ND<\/a>)<\/p>\n<p>In the south-east of Greenland, the ice-sheet margin, which is the edge of the ice sheet and <a href=\"https:\/\/www.geog.cam.ac.uk\/research\/projects\/greenlandicesheet\/\" rel=\"nofollow noopener\" target=\"_blank\">spans 80% of Greenland<\/a>, is rapidly receding, <a href=\"https:\/\/doi.org\/10.1038\/ngeo1481\" rel=\"nofollow noopener\" target=\"_blank\">causing vast ice and habitat loss<\/a>.<\/p>\n<p>The loss of ice is a substantial problem for the polar bears, as this reduces the availability of hunting platforms to catch seals, <a href=\"https:\/\/www.nhm.ac.uk\/discover\/news\/2022\/june\/greenland-polar-bears-learned-hunt-without-sea-ice.html\" rel=\"nofollow noopener\" target=\"_blank\">leading to isolation and food scarcity<\/a>. The north-east of Greenland is a vast, flat Arctic tundra, while south-east Greenland is covered by <a href=\"https:\/\/doi.org\/10.1098\/rstb.2012.0479\" rel=\"nofollow noopener\" target=\"_blank\">forest tundra<\/a> (the transitional zone between coniferous forest and Arctic tundra). The south-east climate has <a href=\"https:\/\/doi.org\/10.1175\/JCLI-D-17-0622.1\" rel=\"nofollow noopener\" target=\"_blank\">high levels of rain, wind, and steep coastal mountains<\/a>.<\/p>\n<p><a href=\"https:\/\/www.sciencealert.com\/newsletter?utm_source=promo_generic_health\" rel=\"nofollow noopener\" target=\"_blank\"><img decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2025\/11\/Generic-Health-Promo-Final-642x273.jpg\" alt=\"Subscribe to ScienceAlert's free fact-checked newsletter\" width=\"642\" height=\"273\" class=\"alignnone wp-image-182810 size-medium\"   loading=\"lazy\"\/><\/a><\/p>\n<p>How climate is changing polar bear DNA<\/p>\n<p>Over time, the DNA sequence can slowly change and evolve, but environmental stress, such as a <a href=\"https:\/\/doi.org\/10.1016\/j.tig.2022.08.006\" rel=\"nofollow noopener\" target=\"_blank\">warmer climate<\/a>, can accelerate this process.<\/p>\n<p>TEs are like puzzle pieces that can rearrange themselves, sometimes helping animals adapt to new environments. In the polar bear genome, <a href=\"https:\/\/doi.org\/10.1093\/gbe\/evx170\" rel=\"nofollow noopener\" target=\"_blank\">approximately 38.1% of the genome is made up of TEs<\/a>. TEs come in many different families and have slightly different behaviours, but in essence, they are all mobile fragments that can reinsert randomly anywhere in the genome.<\/p>\n<p>In the human genome, <a href=\"https:\/\/doi.org\/10.1038\/35057062\" rel=\"nofollow noopener\" target=\"_blank\">45%<\/a> is comprised of TEs, and in plants, it can be <a href=\"https:\/\/genomebiology.biomedcentral.com\/articles\/10.1186\/s13059-018-1577-z\" rel=\"nofollow noopener\" target=\"_blank\">over 70%<\/a>. There are small protective molecules called piwi-interacting RNAs (piRNAs) that can <a href=\"https:\/\/www.cell.com\/trends\/genetics\/fulltext\/S0168-9525(22)00226-8\" rel=\"nofollow noopener\" target=\"_blank\">silence the activity of TEs<\/a>.<\/p>\n<p>Despite this, when an environmental stress is too strong, these protective piRNAs cannot keep up with the invasive actions of TEs. In our work, we found that the warmer south-east climate led to a mass mobilisation from these TEs across the polar bear genome, changing its sequence.<\/p>\n<p>We also found that these TE sequences appeared younger and more abundant in the south-east bears, with over 1,500 of them &#8220;upregulated&#8221;, which suggests recent genetic changes that may help bears adapt to rising temperatures.<\/p>\n<p>Some of these elements overlap with genes linked to stress responses and metabolism, hinting at a possible role in coping with  <a href=\"https:\/\/www.sciencealert.com\/climate-change\" class=\"lar_link lar_link_outgoing\" data-linkid=\"73046\" data-postid=\"185823\" rel=\"nofollow noopener\" target=\"_self\">climate change<\/a>. By studying these jumping genes, we uncovered how the polar bear genome adapts and responds, in the shorter term, to environmental stress and warmer climates.<\/p>\n<p>Our research found that some genes linked to heat stress, ageing, and metabolism are behaving differently in the south-east population of polar bears. This suggests they might be adjusting to their warmer conditions.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2025\/12\/polar_bear_greenery_642.jpg\" alt=\"Polar bear and green plants\" width=\"642\" height=\"450\" class=\"wp-image-185832 size-full\"   loading=\"lazy\"\/>Genes linked to heat stress, ageing, and metabolism are behaving differently in one polar bear population. (<a href=\"https:\/\/www.canva.com\/photos\/MAGzLUXZQqQ\/\" rel=\"nofollow noopener\" target=\"_blank\">Laurence FUSCO\/Pexels\/Canva<\/a>)<\/p>\n<p>Additionally, we found active jumping genes in parts of the genome that are involved in areas tied to fat processing \u2013 important when food is scarce. This could mean that polar bears in the south-east are slowly adapting to eating the rougher plant-based diets that can be found in the warmer regions. Northern populations of bears eat mainly fatty seals.<\/p>\n<p>Overall, climate change is reshaping polar bear habitats, leading to genetic changes, with south-eastern bears evolving to survive these new terrains and diets. Future research could include other polar bear populations living in challenging climates.<\/p>\n<p>Understanding these genetic changes helps researchers see how polar bears might survive in a warming world \u2013 and which populations are most at risk.<img decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2025\/12\/1766005811_897_count.gif\" alt=\"The Conversation\" width=\"1\" height=\"1\" referrerpolicy=\"no-referrer-when-downgrade\" loading=\"lazy\"\/>\n<\/p>\n<p><a href=\"https:\/\/theconversation.com\/profiles\/alice-godden-973532\" rel=\"nofollow noopener\" target=\"_blank\">Alice Godden<\/a>, Senior Research Associate, School of Biological Sciences, <a href=\"https:\/\/theconversation.com\/institutions\/university-of-east-anglia-1268\" rel=\"nofollow noopener\" target=\"_blank\">University of East Anglia<\/a><\/p>\n<p>This article is republished from <a href=\"https:\/\/theconversation.com\" rel=\"nofollow noopener\" target=\"_blank\">The Conversation<\/a> under a Creative Commons license. Read the <a href=\"https:\/\/theconversation.com\/polar-bears-are-adapting-to-climate-change-at-a-genetic-level-and-it-could-help-them-avoid-extinction-269852\" rel=\"nofollow noopener\" target=\"_blank\">original article<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"The Arctic Ocean current is at its warmest in the last 125,000 years, and temperatures continue to rise.&hellip;\n","protected":false},"author":2,"featured_media":190044,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[85,46,141,386],"class_list":{"0":"post-190043","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-wildlife","8":"tag-il","9":"tag-israel","10":"tag-science","11":"tag-wildlife"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/190043","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=190043"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/190043\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/190044"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=190043"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=190043"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=190043"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}