{"id":5975,"date":"2015-03-02T16:44:50","date_gmt":"2015-03-02T15:44:50","guid":{"rendered":"http:\/\/www.grandesterresbio.com\/?p=5975"},"modified":"2015-03-02T16:44:50","modified_gmt":"2015-03-02T15:44:50","slug":"le-secret-de-longevite-des-baobabs","status":"publish","type":"post","link":"https:\/\/claire-jannot.com\/?p=5975","title":{"rendered":"Le secret de long\u00e9vit\u00e9 des baobabs"},"content":{"rendered":"<h2><span style=\"color: #000000;\">Des chercheurs ont perc\u00e9 le secret de l&rsquo;extraordinaire long\u00e9vit\u00e9 des baobabs d&rsquo;Afrique en s&rsquo;int\u00e9ressant \u00e0 l&rsquo;\u00e9trange cavit\u00e9 d&rsquo;un sp\u00e9cimen mozambicain \u00e2g\u00e9 de 900 \u00e0 1.400 ans, form\u00e9 par plusieurs pousses ayant fusionn\u00e9.<\/span><\/h2>\n<p><span style=\"color: #000000;\"><a href=\"https:\/\/i0.wp.com\/www.grandesterresbio.com\/wp-content\/uploads\/2015\/03\/Adansonia_digitata_Baobab.jpg\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" class=\"alignleft wp-image-5976 \" src=\"https:\/\/i0.wp.com\/www.grandesterresbio.com\/wp-content\/uploads\/2015\/03\/Adansonia_digitata_Baobab.jpg?resize=414%2C272\" alt=\"Baobab-www.grandesterresbio.com\" width=\"414\" height=\"272\" srcset=\"https:\/\/i0.wp.com\/claire-jannot.com\/wp-content\/uploads\/2015\/03\/Adansonia_digitata_Baobab.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/claire-jannot.com\/wp-content\/uploads\/2015\/03\/Adansonia_digitata_Baobab.jpg?resize=300%2C196&amp;ssl=1 300w\" sizes=\"auto, (max-width: 414px) 100vw, 414px\" \/><\/a>Le <strong>baobab de Lebombo<\/strong>, embl\u00e9matique des nombreux baobabs dont la silhouette massive et les branches ressemblant \u00e0 des racines ornent les savanes arides du continent, affiche l&rsquo;honorable <strong>circonf\u00e9rence de 21,44 m\u00e8tres<\/strong>, selon un article publi\u00e9 r\u00e9cemment par la revue scientifique PLoS One.<\/span><\/p>\n<p><span style=\"color: #000000;\">Situ\u00e9 pr\u00e8s du c\u00e9l\u00e8bre parc sud-africain Kruger, l&rsquo;arbre est sur un sentier \u00e9cologique ferm\u00e9 aux touristes.\u00a0<\/span><span style=\"color: #000000;\">\u00ab\u00a0Il a un aspect singulier avec de <strong>longues branches \u00e9voquant des d\u00e9fenses de mammouths<\/strong>\u00ab\u00a0, pr\u00e9cisent les sept auteurs, qui ont cependant d\u00e9laiss\u00e9 la po\u00e9sie de ses branches pour effectuer un carottage du tronc \u00e0 l&rsquo;aide d&rsquo;une petite foreuse. <\/span><br \/>\n<span style=\"color: #000000;\">Les recherches ont d\u00e9marr\u00e9 en 2005 pour <strong>\u00ab\u00a0comprendre les aspects controvers\u00e9s ou m\u00e9connus de l&rsquo;architecture, de la croissance et de l&rsquo;\u00e2ge du baobab\u00a0\u00bb<\/strong>, en latin Adansonia Digitata.<\/span><br \/>\n<span style=\"color: #000000;\">Des \u00e9chantillons ont \u00e9t\u00e9 collect\u00e9s depuis l&rsquo;int\u00e9rieur de la cavit\u00e9, et d&rsquo;autres en forant depuis le pourtour ext\u00e9rieur du tronc. Et l\u00e0, surprise, <strong>la datation au carbone a r\u00e9v\u00e9l\u00e9 que la partie la plus \u00e2g\u00e9e de l&rsquo;arbre \u00e9tait pr\u00e9lev\u00e9e depuis l&rsquo;int\u00e9rieur de l&rsquo;arbre.<\/strong> Sur les autres esp\u00e8ces d&rsquo;arbre, la partie la plus \u00e2g\u00e9e part de l&rsquo;\u00e9corce pour rajeunir \u00e0 mesure que l&rsquo;on va vers son coeur.\u00a0<\/span><br \/>\n<span style=\"color: #000000;\">\u00ab\u00a0La seule explication possible pour cette d\u00e9couverte est que ces cavit\u00e9s, que nous appelons fausses cavit\u00e9s, sont en r\u00e9alit\u00e9 <strong>des espaces naturellement vides<\/strong> (qui n&rsquo;ont jamais \u00e9t\u00e9 remplis par du bois) entre plusieurs pousses dispos\u00e9es suivant une forme circulaire et qui ont fusionn\u00e9\u00a0\u00bb, ajoutent-ils.\u00a0<\/span><span style=\"color: #000000;\">L&rsquo;exercice de <strong>datation au carbone<\/strong> a \u00e9t\u00e9 r\u00e9p\u00e9t\u00e9 sur d&rsquo;autres baobabs \u00e0 fausse cavit\u00e9, aboutissant \u00e0 la m\u00eame conclusion. \u00ab\u00a0Nous avons trouv\u00e9 que cette nouvelle architecture permet aux baobabs d&rsquo;atteindre une taille plus large et un \u00e2ge plus avanc\u00e9\u00a0\u00bb, soulignent les auteurs.<\/span><br \/>\n<span style=\"color: #000000;\">Quant au baobab de Lebombo, cette recherche le fait entrer au panth\u00e9on des <strong>plus vieux arbres du continent: son apparition remonterait \u00e0 l&rsquo;an 600, ce qui en fait \u00ab\u00a0l&rsquo;un des plus vieux baobabs d&rsquo;Afrique\u00a0\u00bb<\/strong>.<\/span><\/p>\n<address><span style=\"color: #000000;\">Source :\u00a0JOHANNESBURG,\u00a019 f\u00e9v 2015 (AFP)<\/span><\/address>\n<address><span style=\"color: #000000;\">Cr\u00e9dit photo :\u00a0By Yoky (Own work) [GFDL (http:\/\/www.gnu.org\/copyleft\/fdl.html) or CC BY-SA 3.0 (http:\/\/creativecommons.org\/licenses\/by-sa\/3.0)], via Wikimedia Commons<\/span><\/address>\n<address>\u00a0<\/address>\n<address>\u00a0<\/address>\n<address>\u00a0<\/address>\n<address>\u00a0<\/address>\n<address>\u00a0<\/address>\n<address>\u00a0<\/address>\n","protected":false},"excerpt":{"rendered":"<p>Des chercheurs ont perc\u00e9 le secret de l&rsquo;extraordinaire long\u00e9vit\u00e9 des baobabs d&rsquo;Afrique en s&rsquo;int\u00e9ressant \u00e0 l&rsquo;\u00e9trange cavit\u00e9 d&rsquo;un sp\u00e9cimen mozambicain \u00e2g\u00e9 de 900 \u00e0 1.400 ans, form\u00e9 par plusieurs pousses ayant fusionn\u00e9. Le baobab de Lebombo, embl\u00e9matique des nombreux baobabs &hellip; <a href=\"https:\/\/claire-jannot.com\/?p=5975\">Continuer la lecture <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[2],"tags":[22,4,5,27],"class_list":["post-5975","post","type-post","status-publish","format-standard","hentry","category-ecologie","tag-biologique","tag-ecologie2","tag-environnement","tag-insolite"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p5jjt5-1yn","_links":{"self":[{"href":"https:\/\/claire-jannot.com\/index.php?rest_route=\/wp\/v2\/posts\/5975","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/claire-jannot.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/claire-jannot.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/claire-jannot.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/claire-jannot.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=5975"}],"version-history":[{"count":1,"href":"https:\/\/claire-jannot.com\/index.php?rest_route=\/wp\/v2\/posts\/5975\/revisions"}],"predecessor-version":[{"id":5977,"href":"https:\/\/claire-jannot.com\/index.php?rest_route=\/wp\/v2\/posts\/5975\/revisions\/5977"}],"wp:attachment":[{"href":"https:\/\/claire-jannot.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5975"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/claire-jannot.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5975"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/claire-jannot.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5975"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}