{"id":244028,"date":"2026-01-14T10:49:08","date_gmt":"2026-01-14T10:49:08","guid":{"rendered":"https:\/\/www.newsbeep.com\/ie\/244028\/"},"modified":"2026-01-14T10:49:08","modified_gmt":"2026-01-14T10:49:08","slug":"worlds-longest-living-sharks-may-hold-clues-to-preserving-vision-for-life-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ie\/244028\/","title":{"rendered":"World&#8217;s Longest-Living Sharks May Hold Clues to Preserving Vision For Life : ScienceAlert"},"content":{"rendered":"<p>A new analysis of the eyes of some of the <a href=\"https:\/\/www.sciencealert.com\/10-animals-that-live-way-longer-than-humans\" rel=\"nofollow noopener\" target=\"_blank\">longest-lived animals<\/a> on Earth could provide molecular clues about long-lasting vision.<\/p>\n<p>Scientists had long assumed that Greenland sharks (<a href=\"https:\/\/en.wikipedia.org\/wiki\/Greenland_shark\" rel=\"nofollow noopener\" target=\"_blank\">Somniosus microcephalus<\/a>) have, at best, exceedingly poor vision. They spend most of their <a href=\"https:\/\/www.sciencealert.com\/scientists-just-discovered-a-shark-that-s-400-years-old-living-in-the-arctic\" rel=\"nofollow noopener\" target=\"_blank\">centuries-long<\/a> lives <a href=\"https:\/\/www.sciencealert.com\/rarely-glimpsed-shark-that-lives-for-centuries-unexpectedly-surfaces-in-caribbean\" rel=\"nofollow noopener\" target=\"_blank\">in the dim depths of the ocean<\/a>, often sporting parasites attached to their <a href=\"https:\/\/en.wikipedia.org\/wiki\/Cornea\" rel=\"nofollow noopener\" target=\"_blank\">corneas<\/a>.<\/p>\n<p>A team of researchers from the US, Switzerland, and Denmark has now found that Greenland sharks can see \u2013 and retain a functional visual system for quite a long time.<\/p>\n<p>This finding suggests that some aspect of the remarkable DNA repair toolkit linked to the sharks&#8217; exceptional longevity may help keep their retinas unusually sprightly\u2026 although it&#8217;s unclear if this will have implications for <a href=\"https:\/\/www.sciencealert.com\/your-eyes-can-shed-light-on-underlying-health-problems\" rel=\"nofollow noopener\" target=\"_blank\">human eye health<\/a>.<\/p>\n<p>Related: <a href=\"https:\/\/www.sciencealert.com\/the-genome-of-the-greenland-shark-reveals-the-secrets-to-its-longevity\" rel=\"nofollow noopener\" target=\"_blank\">The Genome of The Greenland Shark Reveals The Secrets to Its Longevity<\/a><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.newsbeep.com\/ie\/wp-content\/uploads\/2026\/01\/1768387747_657_0.jpg\" alt=\"YouTube Thumbnail\" tabindex=\"0\" role=\"button\" class=\"youtube-thumbnail-preview\" loading=\"lazy\"\/> frameborder=&#8221;0\u2033 allow=&#8221;accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share&#8221; referrerpolicy=&#8221;strict-origin-when-cross-origin&#8221; allowfullscreen&gt;<\/p>\n<p>The research was conducted on the eyes of Greenland sharks caught and euthanized between 2020 and 2024 under a research permit issued by the territory&#8217;s government. These sharks all had <a href=\"https:\/\/doi.org\/10.1126\/science.aaf1703\" rel=\"nofollow noopener\" target=\"_blank\">estimated ages<\/a> of more than a century, with the oldest estimated at more than 130 years.<\/p>\n<p>Greenland sharks spend most of their time in deep waters, up to <a href=\"https:\/\/www.floridamuseum.ufl.edu\/discover-fish\/species-profiles\/greenland-shark\/\" rel=\"nofollow noopener\" target=\"_blank\">1,200 meters<\/a> (3,940 feet) below the surface, although they can dive deeper. At these depths, there&#8217;s very little light; starting at 100 meters, the amount that can penetrate the water column <a href=\"https:\/\/www.whoi.edu\/ocean-learning-hub\/ocean-topics\/how-the-ocean-works\/ocean-zones\/\" rel=\"nofollow noopener\" target=\"_blank\">drops off steeply<\/a>. Below about 1,000 meters, there&#8217;s effectively no sunlight at all.<\/p>\n<p>This, combined with the prevalence of ocular parasites, led many scientists to conclude that these fish could live with little to no visual acuity. The team&#8217;s molecular, genomic, and tissue-structure examination of the Greenland sharks&#8217; eyes has proven otherwise.<\/p>\n<p><a href=\"https:\/\/www.sciencealert.com\/we-may-finally-know-how-our-eyesight-evolved-and-its-not-from-our-branch-of-life\" rel=\"nofollow noopener\" target=\"_blank\">Vertebrate retinas<\/a> typically have rods and cones \u2013 <a href=\"https:\/\/en.wikipedia.org\/wiki\/Photoreceptor_cell\" rel=\"nofollow noopener\" target=\"_blank\">types of light-sensing cells<\/a>. <a href=\"https:\/\/en.wikipedia.org\/wiki\/Rod_cell\" rel=\"nofollow noopener\" target=\"_blank\">Rods<\/a> are optimized for vision in low-light conditions, while <a href=\"https:\/\/en.wikipedia.org\/wiki\/Cone_cell\" rel=\"nofollow noopener\" target=\"_blank\">cones<\/a> support color vision in brighter conditions. The retina of the Greenland shark has no cones at all \u2013 an adaptation found in a handful of <a href=\"https:\/\/www.sciencealert.com\/this-fish-has-a-weird-see-through-head-with-its-eyes-on-the-inside-heres-why\" rel=\"nofollow noopener\" target=\"_blank\">animals that spend the majority of their time in low-light conditions<\/a>.<\/p>\n<p>The researchers also tested their <a href=\"https:\/\/en.wikipedia.org\/wiki\/Rhodopsin\" rel=\"nofollow noopener\" target=\"_blank\">rhodopsin<\/a>, a <a href=\"https:\/\/www.sciencealert.com\/a-special-protein-in-whale-eyes-reveals-a-long-history-of-diving-to-extreme-depths\" rel=\"nofollow noopener\" target=\"_blank\">highly light-sensitive protein<\/a> in rod cells that is essential for low-light vision. The sensitivity of rhodopsin in Greenland sharks peaks at around 458 nanometers \u2013 the blue wavelength at which the faint light that reaches the sharks&#8217; habitat is strongest.<\/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\/ie\/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>The shark retinas the researchers studied were healthy, with no signs of degeneration, even at ages over 100 years, although the <a href=\"https:\/\/www.sciencealert.com\/tardigrades-have-a-genetic-secret-and-it-could-boost-human-resilience\" rel=\"nofollow noopener\" target=\"_blank\">DNA repair<\/a> mechanism that might maintain them is yet to be explored. Corneal measurements show that these structures continue to transmit most of the incoming light, even when a parasite is attached.<\/p>\n<p>Taken together, the results suggest that Greenland sharks are exceptionally well adapted for permanent night vision in the <a href=\"https:\/\/www.sciencealert.com\/deep-sea-pearlside-fish-new-eye-cells-twilight\" rel=\"nofollow noopener\" target=\"_blank\">dark depths of the ocean<\/a> where they live.<\/p>\n<p>Related: <a href=\"https:\/\/www.sciencealert.com\/the-weirdest-eyes-in-the-animal-kingdom-see-a-world-we-can-t-imagine\" rel=\"nofollow noopener\" target=\"_blank\">The Weirdest Eyes in The Animal Kingdom See a World We Can&#8217;t Imagine<\/a><\/p>\n<p>&#8220;Our findings support the presence of a preserved and functional visual system in the adult Greenland shark, which seems well-adapted to extreme low-light conditions,&#8221; <a href=\"https:\/\/doi.org\/10.1038\/s41467-025-67429-6\" rel=\"nofollow noopener\" target=\"_blank\">the researchers write in their paper<\/a>.<\/p>\n<p>&#8220;The Greenland shark provides a striking example of long-term preservation of retinal integrity, supported at both molecular and histological levels, and highlights the extraordinary potential for neuronal maintenance in extreme longevity.&#8221;<\/p>\n<p>The research has been published in <a href=\"https:\/\/doi.org\/10.1038\/s41467-025-67429-6\" rel=\"nofollow noopener\" target=\"_blank\">Nature Communications<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"A new analysis of the eyes of some of the longest-lived animals on Earth could provide molecular clues&hellip;\n","protected":false},"author":2,"featured_media":244029,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[61,60,2209,82,263],"class_list":{"0":"post-244028","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-wildlife","8":"tag-ie","9":"tag-ireland","10":"tag-msft-content","11":"tag-science","12":"tag-wildlife"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/244028","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/comments?post=244028"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/posts\/244028\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media\/244029"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/media?parent=244028"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/categories?post=244028"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ie\/wp-json\/wp\/v2\/tags?post=244028"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}