\u201cPotentially biogenic carbon preserved in a 4.1 billion-year-old zircon\u201d<\/a><\/p>\n\u00a0<\/p>\n
\u201cTo our knowledge,\u201d say the four authors of the article (three from the Department of Earth, Planetary, and Space Sciences at the University of California at Los Angeles, and one from Stanford University\u2019s School of Earth, Energy, and Environmental Sciences), \u201cwe report here the first unambiguous carbon isotopic measurements of terrestrial Hadean material.\u201d \u00a0What they have identified, they think, \u201cmay be evidence for the origin of life on Earth by 4.1 Ga.\u201d<\/p>\n
\u00a0<\/p>\n
[In the article and its abstract, the abbreviations Ga<\/em> and My<\/em> refer, respectively, to a \u201cgiga-annum\u201d (or a billion years) and to \u201ca million years.\u201d]<\/p>\n\u00a0<\/p>\n
\n
\n
\n
The abstract of the article reads as follows:<\/p>\n
\u00a0<\/p>\n
Evidence of life on Earth is manifestly preserved in the rock record. However, the microfossil record only extends to \u223c3.5 billion years (Ga), the chemofossil record arguably to \u223c3.8 Ga, and the rock record to 4.0 Ga. Detrital zircons from Jack Hills, Western Australia range in age up to nearly 4.4 Ga. From a population of over 10,000 Jack Hills zircons, we identified one >3.8-Ga zircon that contains primary graphite inclusions. Here, we report carbon isotopic measurements on these inclusions in a concordant, 4.10 \u00b1 0.01-Ga zircon. We interpret these inclusions as primary due to their enclosure in a crack-free host as shown by transmission X-ray microscopy and their crystal habit. Their \u03b413CPDB of \u221224 \u00b1 5\u2030 is consistent with a biogenic origin and may be evidence that a terrestrial biosphere had emerged by 4.1 Ga, or \u223c300 My earlier than has been previously proposed.\u00a0<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n\u00a0<\/p>\n
And here is their concluding paragraph:<\/p>\n
\u00a0<\/p>\n
\n
\n
\n
\n
\n
\n
This study extends the terrestrial carbon isotope record \u223c300 My beyond the previously oldest-measured samples from southwest Greenland. Our interpretation that the light C isotope signature in primary graphitic inclusions could reflect biologic processes is consistent with an estimate from molecular divergence in prokaryote phylogenetic relationships that a terrestrial biosphere had emerged by 4.1 Ga. Confirming such a connection would represent a potentially transformational scientific advance. However, given the low occurrence of carbon-bearing Hadean zircons, establishing a Hadean carbon cycle and its possible bearing on the origin of life will require enormous and sustained efforts.<\/span><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\u00a0<\/p>\n
Once again, it seems that life may have appeared on the Earth at the earliest time that it possibly could. \u00a0That\u2019s an arresting fact.<\/p>\n
\u00a0<\/p>\n
\u00a0<\/p>\n<\/body><\/html>\n","protected":false},"excerpt":{"rendered":"
\u00a0 \u00a0 The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years ago: \u00a0 \u201cAn amazing thought: \u201cNew find could be oldest evidence of life ever discovered\u201d\u201d \u00a0 I thought this astoundingly early, given the fact that the Earth itself isn\u2019t much older […]<\/p>\n","protected":false},"author":1019,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-71506","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"yoast_head":"\n
"A potential biosignature" at 4.1 billion years before the present?<\/title>\n<meta name=\"description\" content=\" The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\""A potential biosignature" at 4.1 billion years before the present?\" \/>\n<meta property=\"og:description\" content=\" The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html\" \/>\n<meta property=\"og:site_name\" content=\"Sic et Non\" \/>\n<meta property=\"article:published_time\" content=\"2019-03-13T20:54:08+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2019-03-13T21:09:33+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/wp-media.patheos.com\/blogs\/sites\/186\/2019\/03\/JackHills_Location.jpg\" \/>\n<meta name=\"author\" content=\"Dan Peterson\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"Dan Peterson\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html\",\"url\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html\",\"name\":\"\\\"A potential biosignature\\\" at 4.1 billion years before the present?\",\"isPartOf\":{\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/#website\"},\"datePublished\":\"2019-03-13T20:54:08+00:00\",\"dateModified\":\"2019-03-13T21:09:33+00:00\",\"author\":{\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/#\/schema\/person\/77113e9b09701bd1599fa272c4f65045\"},\"description\":\" The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years\",\"breadcrumb\":{\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"“A potential biosignature” at 4.1 billion years before the present?\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/#website\",\"url\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/\",\"name\":\"Sic et Non\",\"description\":\"\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"en-US\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/#\/schema\/person\/77113e9b09701bd1599fa272c4f65045\",\"name\":\"Dan Peterson\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/secure.gravatar.com\/avatar\/5ed1a72d26805e35a503e3167599df7c?s=96&d=mm&r=g\",\"contentUrl\":\"https:\/\/secure.gravatar.com\/avatar\/5ed1a72d26805e35a503e3167599df7c?s=96&d=mm&r=g\",\"caption\":\"Dan Peterson\"},\"description\":\"\\\"Life was very unsatisfying until I discovered Dan's blog, which gave me a reason to live.\\\" (gemli, 7 November 2019)\",\"url\":\"https:\/\/www.patheos.com\/blogs\/danpeterson\/author\/danpeterson\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"\"A potential biosignature\" at 4.1 billion years before the present?","description":" The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html","og_locale":"en_US","og_type":"article","og_title":"\"A potential biosignature\" at 4.1 billion years before the present?","og_description":" The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years","og_url":"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html","og_site_name":"Sic et Non","article_published_time":"2019-03-13T20:54:08+00:00","article_modified_time":"2019-03-13T21:09:33+00:00","og_image":[{"url":"https:\/\/wp-media.patheos.com\/blogs\/sites\/186\/2019\/03\/JackHills_Location.jpg"}],"author":"Dan Peterson","twitter_card":"summary_large_image","twitter_misc":{"Written by":"Dan Peterson","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html","url":"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html","name":"\"A potential biosignature\" at 4.1 billion years before the present?","isPartOf":{"@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/#website"},"datePublished":"2019-03-13T20:54:08+00:00","dateModified":"2019-03-13T21:09:33+00:00","author":{"@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/#\/schema\/person\/77113e9b09701bd1599fa272c4f65045"},"description":" The other day, I posted some thoughts regarding a 2017 article proposing evidence of terrestrial life between 3.77 and 4.28 billion years","breadcrumb":{"@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/2019\/03\/a-potential-biosignature-at-4-1-billion-years-before-the-present.html#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/www.patheos.com\/blogs\/danpeterson"},{"@type":"ListItem","position":2,"name":"“A potential biosignature” at 4.1 billion years before the present?"}]},{"@type":"WebSite","@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/#website","url":"https:\/\/www.patheos.com\/blogs\/danpeterson\/","name":"Sic et Non","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.patheos.com\/blogs\/danpeterson\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/#\/schema\/person\/77113e9b09701bd1599fa272c4f65045","name":"Dan Peterson","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/www.patheos.com\/blogs\/danpeterson\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/5ed1a72d26805e35a503e3167599df7c?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/5ed1a72d26805e35a503e3167599df7c?s=96&d=mm&r=g","caption":"Dan Peterson"},"description":"\"Life was very unsatisfying until I discovered Dan's blog, which gave me a reason to live.\" (gemli, 7 November 2019)","url":"https:\/\/www.patheos.com\/blogs\/danpeterson\/author\/danpeterson"}]}},"_links":{"self":[{"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/posts\/71506","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/users\/1019"}],"replies":[{"embeddable":true,"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/comments?post=71506"}],"version-history":[{"count":0,"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/posts\/71506\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/media?parent=71506"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/categories?post=71506"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.patheos.com\/blogs\/danpeterson\/wp-json\/wp\/v2\/tags?post=71506"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
![\"Australia](\"https:\/\/wp-media.patheos.com\/blogs\/sites\/186\/2019\/03\/JackHills_Location.jpg\")
<\/a>