{"id":154140,"date":"2023-01-01T20:22:46","date_gmt":"2023-01-02T02:22:46","guid":{"rendered":"https:\/\/lifeboat.com\/blog\/2023\/01\/earth-may-have-briefly-supported-complex-life-long-before-we-arrived"},"modified":"2023-01-01T20:22:46","modified_gmt":"2023-01-02T02:22:46","slug":"earth-may-have-briefly-supported-complex-life-long-before-we-arrived","status":"publish","type":"post","link":"https:\/\/lifeboat.com\/blog\/2023\/01\/earth-may-have-briefly-supported-complex-life-long-before-we-arrived","title":{"rendered":"Earth May Have Briefly Supported Complex Life Long Before We Arrived"},"content":{"rendered":"<p><a class=\"aligncenter blog-photo\" href=\"https:\/\/lifeboat.com\/blog.images\/earth-may-have-briefly-supported-complex-life-long-before-we-arrived2.jpg\"><\/a><\/p>\n<p>Complex life on Earth is generally thought to have appeared at least 1.75 billion years ago. But a new study suggests there may have been an earlier period where complex life could have evolved, before disappearing and then reappearing again.<\/p>\n<p>The theory was put forward by a study led by the University of Washington, published today in the <a href=\"http:\/\/www.pnas.org\/content\/early\/2017\/01\/10\/1615867114.abstract\">Proceedings of the National Academy of Sciences<\/a>. They describe how isotopic ratios in the element selenium in sedimentary rocks suggest a high presence of oxygen in Earth\u2019s atmosphere between 2 and 2.4 billion years ago.<\/p>\n<p>The suggestion is that for this relatively brief period in Earth\u2019s 4.5-billion-year history, conditions may have been favorable for complex life. Previously, it had been thought that oxygen on Earth went through a period of none, then some, then a lot, when eukaryotes \u2013 animals, plants, fungi, and protists \u2013 came into existence. But this research suggests there was a spike before \u201cnone\u201d and that it dropped down again.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Complex life on Earth is generally thought to have appeared at least 1.75 billion years ago. But a new study suggests there may have been an earlier period where complex life could have evolved, before disappearing and then reappearing again. The theory was put forward by a study led by the University of Washington, published [\u2026]<\/p>\n","protected":false},"author":661,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20],"tags":[],"class_list":["post-154140","post","type-post","status-publish","format-standard","hentry","category-futurism"],"_links":{"self":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/154140","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/users\/661"}],"replies":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/comments?post=154140"}],"version-history":[{"count":0,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/154140\/revisions"}],"wp:attachment":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/media?parent=154140"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/categories?post=154140"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/tags?post=154140"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}