{"id":631100,"date":"2026-06-10T12:08:14","date_gmt":"2026-06-10T12:08:14","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/631100\/"},"modified":"2026-06-10T12:08:14","modified_gmt":"2026-06-10T12:08:14","slug":"sex-jumpstarted-earths-animal-biodiversity","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/631100\/","title":{"rendered":"Sex jumpstarted Earth’s animal biodiversity"},"content":{"rendered":"

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Evolution is responsible for Earth\u2019s stunningly diverse spectrum of life<\/a>, but that wasn\u2019t always the case. In fact, the earliest eras of living organisms<\/a> were comparatively boring. The earliest known animals date back about 635 million years (during the Ediacaran Period), yet they look remarkably similar to their descendents 96 million years later at the dawn of the Cambrian.<\/p>\n

Why did evolution remain so stable for so long? It might be simply because Earth\u2019s first creatures simply weren\u2019t having much sex.<\/p>\n

\u201cLife was pretty nice during the Ediacaran, so the need for sex was rather limited,\u201d Emily Mitchell, a paleozoologist at the University of Cambridge, explained in a statement<\/a>. \u201cThere was relatively little competition, so there was no real pressure to change anything.\u201d<\/p>\n

Along with her colleague Andrea Manica, Mitchell recently combined spatial analysis and laser scanning with machine learning to analyze 574-million-year-old fossils excavated from southernmost Newfoundland\u2019s Mistaken Point. Their findings, published today in the journal Nature Ecology & Evolution<\/a>, show that the earliest animals\u2019 reliance on asexual reproduction kept things largely uniform, and reduced the struggle for resources.<\/p>\n

\"FossilsFossils of Fractofusus, an animal from the Ediacaran period. Credit: Emily Mitchell<\/a> <\/p>\n

They offered Fractofusus as a prime example. At over 6.5 feet tall, the fern-like creatures dwarfed most of their oceanic relatives and likely lacked organs or mouths. They also absorbed food from the surrounding water while remaining anchored in place, reproducing through clones distributed by stolons or runners like present-day strawberry plants.<\/p>\n

\u201cIf you\u2019re connected to your neighbor by these runners, then you\u2019re sharing nutrients and you don\u2019t need to compete with them,\u201d said Manica.<\/p>\n

From there, the team constructed a machine learning model to approximate how Fractofusus and its fellow Ediacaran animals possibly behaved through varying reproductive strategies. The program\u2019s neural network then identified simulations that aligned with known fossil record diversity patterns. Known as Approximate Bayesian Computation let them basically travel back in time to estimate how animals proliferated and squared off for limited resources.<\/p>\n

They now believe the Ediacaran Period\u2019s overall tranquility (and sexlessness) began to get complicated as species gradually migrated from deep waters to shallower regions. Once there, ancient animals endured new stressors like temperature swings, nutrient deficits, tides, and even storms. Life then adapted to face these increased threats\u2014and left behind more fossils. The story they tell indicates that environmental stress often precedes a rise in sexual reproduction versus other methods of procreation.\u00a0<\/p>\n

\u201cWhen that happens, we can see a massive increase in dispersal distances as animals attempt to colonize new areas due to an increase in competition,\u201d said Mitchell.<\/p>\n

These shifting trends eventually ushered in what\u2019s known as the Ediacaran \u201csecond wave\u201d of animal evolution, which further amplified millions of years later during the Cambrian era, as animals started physically moving through their environments.<\/p>\n

\u201cIf you\u2019re suddenly in an environment where you\u2019re essentially getting killed a couple of times per year, then that changes everything,\u201d Mitchell explained.<\/p>\n

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Andrew Paul is a staff writer for Popular Science.<\/p>\n","protected":false},"excerpt":{"rendered":"Get the Popular Science daily newsletter\ud83d\udca1 Breakthroughs, discoveries, and DIY tips sent six days a week. By signing…\n","protected":false},"author":2,"featured_media":631101,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[22],"tags":[1397,16063,50,90,7335,56,54,55],"class_list":["post-631100","post","type-post","status-publish","format-standard","has-post-thumbnail","category-environment","tag-environment","tag-fossils","tag-news","tag-science","tag-sex","tag-uk","tag-united-kingdom","tag-unitedkingdom"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/631100","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=631100"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/631100\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/631101"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=631100"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=631100"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=631100"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}