{"id":2561,"date":"2023-09-06T00:37:01","date_gmt":"2023-09-06T00:37:01","guid":{"rendered":"https:\/\/campusunivers.com\/?p=2561"},"modified":"2023-09-06T00:39:07","modified_gmt":"2023-09-06T00:39:07","slug":"lhumanite-a-frole-lextinction-perdant-98-7-de-sa-population","status":"publish","type":"post","link":"https:\/\/campusunivers.com\/?p=2561","title":{"rendered":"L&rsquo;humanit\u00e9 a fr\u00f4l\u00e9 l&rsquo;extinction, perdant 98.7% de sa population"},"content":{"rendered":"\n<p>Une nouvelle \u00e9tude r\u00e9v\u00e8le que la population mondiale humaine a vraisemblablement \u00e9t\u00e9 r\u00e9duite \u00e0 environ 1 300 individus pendant plus de 100 000 ans, il y a pr\u00e8s d&rsquo;un million d&rsquo;ann\u00e9es. Ce goulot d&rsquo;\u00e9tranglement d\u00e9mographique pourrait avoir des implications majeures sur l&rsquo;\u00e9volution des humains modernes et de leurs plus proches parents disparus, les N\u00e9andertaliens et les D\u00e9nisoviens.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/l-humanite-a-frole-lextinction.jpeg?resize=800%2C449&#038;ssl=1\" alt=\"\" class=\"wp-image-2563\" style=\"width:860px;height:483px\" width=\"800\" height=\"449\" srcset=\"https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/l-humanite-a-frole-lextinction.jpeg?w=534&amp;ssl=1 534w, https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/l-humanite-a-frole-lextinction.jpeg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"auto, (max-width: 800px) 100vw, 800px\" \/><figcaption class=\"wp-element-caption\"><em>L&rsquo;humanit\u00e9 a fr\u00f4l\u00e9 l&rsquo;extinction, perdant 98.7% de sa population\u00a9&nbsp;Fournis par Techno-Science<\/em><\/figcaption><\/figure>\n\n\n\n<p><em>Art rupestre sur une falaise illustrant comment nos anc\u00eatres humains ont surv\u00e9cu face \u00e0 des dangers inconnus. \u00c0 c\u00f4t\u00e9, la formule de base utilis\u00e9e par les chercheurs pour d\u00e9duire le goulot d&rsquo;\u00e9tranglement qui s&rsquo;est produit il y a pr\u00e8s d&rsquo;un million d&rsquo;ann\u00e9es.<\/em><\/p>\n\n\n\n<p><em>Cr\u00e9dit: Shanghai Institute of Nutrition and Health, CAS<\/em><\/p>\n\n\n\n<p>Des recherches ant\u00e9rieures sugg\u00e8rent que les humains modernes sont apparus il y a environ 300 000 ans en Afrique. Pour en savoir plus sur cette p\u00e9riode, les scientifiques ont analys\u00e9 les g\u00e9nomes de plus de 3 150 humains modernes actuels issus de 10 populations africaines et 40 non-africaines. Ils ont d\u00e9velopp\u00e9 un nouvel outil analytique pour estimer la taille de la population ancestrale.<\/p>\n\n\n\n<p>Les donn\u00e9es g\u00e9n\u00e9tiques indiquent qu&rsquo;entre 813 000 et 930 000 ans, les anc\u00eatres des humains modernes ont connu un s\u00e9v\u00e8re goulot d&rsquo;\u00e9tranglement, perdant environ 98,7 % de sa population reproductrice. Wangjie Hu, co-auteur principal de l&rsquo;\u00e9tude \u00e0 l&rsquo;Icahn School of Medicine \u00e0 New York, souligne que nos anc\u00eatres ont couru un risque \u00e9lev\u00e9 d&rsquo;<a href=\"https:\/\/www.techno-science.net\/definition\/3481.html\" target=\"_blank\" rel=\"noreferrer noopener\">extinction<\/a>.<\/p>\n\n\n\n<p>Chris Stringer, pal\u00e9oanthropologue au Natural History Museum de Londres, note que cette r\u00e9duction de la population co\u00efncide avec un refroidissement climatique important, entra\u00eenant l&rsquo;apparition de glaciers et peut-\u00eatre de longues s\u00e9cheresses en Afrique et en Eurasie.<\/p>\n\n\n\n<p><\/p>\n\n\n\n<figure class=\"wp-block-image size-full is-resized\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" src=\"https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/CP-Science.jpeg?resize=708%2C398&#038;ssl=1\" alt=\"\" class=\"wp-image-2562\" style=\"width:708px;height:398px\" width=\"708\" height=\"398\" srcset=\"https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/CP-Science.jpeg?w=534&amp;ssl=1 534w, https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/CP-Science.jpeg?resize=300%2C169&amp;ssl=1 300w\" sizes=\"auto, (max-width: 708px) 100vw, 708px\" \/><figcaption class=\"wp-element-caption\"><em>Ce graphique montre la chronologie du goulot d&rsquo;\u00e9tranglement s\u00e9v\u00e8re et combien d&rsquo;individus existaient probablement \u00e0 cette \u00e9poque <\/em><br>\u00a9&nbsp;Fournis par Techno-Science<em>.<\/em><\/figcaption><\/figure>\n\n\n\n<p><em>Ce graphique montre la chronologie du goulot d&rsquo;\u00e9tranglement s\u00e9v\u00e8re et combien d&rsquo;individus existaient probablement \u00e0 cette \u00e9poque.<\/em><\/p>\n\n\n\n<p><em>Cr\u00e9dit: Image by Science<\/em><\/p>\n\n\n\n<p>Les derniers anc\u00eatres communs aux humains modernes, les N\u00e9andertaliens et les D\u00e9nisoviens, aurait v\u00e9cu \u00e0 peu pr\u00e8s au m\u00eame moment que ce goulot d&rsquo;\u00e9tranglement. Chris Stringer explique que ce ph\u00e9nom\u00e8ne pourrait avoir jou\u00e9 un r\u00f4le dans la divergence entre ces groupes humains. De plus, une fusion chromosomique majeure co\u00efncide avec cette p\u00e9riode, sugg\u00e9rant un lien possible avec ce changement g\u00e9nomique.<\/p>\n\n\n\n<p><strong>Source:<\/strong>&nbsp;<a rel=\"noreferrer noopener\" href=\"http:\/\/www.science.org\/doi\/10.1126\/science.abq7487\" target=\"_blank\">Science<\/a>, Adrien BERNARD<\/p>\n\n\n\n<p><a href=\"https:\/\/www.msn.com\/fr-fr\/actualite\/technologie-et-sciences\/l-humanit%C3%A9-a-fr%C3%B4l%C3%A9-l-extinction-perdant-98-7-de-sa-population\/ar-AA1ggyWX?ocid=msedgntp&amp;cvid=9a90616dc29e4371aa017774d2bf42c4&amp;ei=26\">L&rsquo;humanit\u00e9 a fr\u00f4l\u00e9 l&rsquo;extinction, perdant 98.7% de sa population (msn.com)<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Une nouvelle \u00e9tude r\u00e9v\u00e8le que la population mondiale humaine a vraisemblablement \u00e9t\u00e9 r\u00e9duite \u00e0 environ 1 300 individus pendant plus<\/p>\n","protected":false},"author":1,"featured_media":2564,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"colormag_page_container_layout":"default_layout","colormag_page_sidebar_layout":"default_layout","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[25,26,27,29],"tags":[],"class_list":["post-2561","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-actualites","category-campuslife","category-debats-opinions","category-science-technique"],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/campusunivers.com\/wp-content\/uploads\/2023\/09\/l-humanite-a-frole-lextinction-CP-Sciences.jpg?fit=1068%2C600&ssl=1","jetpack-related-posts":[],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/posts\/2561","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/campusunivers.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2561"}],"version-history":[{"count":2,"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/posts\/2561\/revisions"}],"predecessor-version":[{"id":2566,"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/posts\/2561\/revisions\/2566"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/campusunivers.com\/index.php?rest_route=\/wp\/v2\/media\/2564"}],"wp:attachment":[{"href":"https:\/\/campusunivers.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2561"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/campusunivers.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2561"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/campusunivers.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2561"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}