{"id":16934,"date":"2022-08-17T17:00:29","date_gmt":"2022-08-17T15:00:29","guid":{"rendered":"https:\/\/www.sciencefocus.com\/?p=126465"},"modified":"2022-08-17T17:19:08","modified_gmt":"2022-08-17T15:19:08","slug":"bizarre-minion-like-creature-with-no-anus-is-not-our-earliest-known-ancestor-after-all","status":"publish","type":"rss_feed","link":"https:\/\/c01.purpledshub.com\/bbcsciencefocus\/rss_feed\/bizarre-minion-like-creature-with-no-anus-is-not-our-earliest-known-ancestor-after-all\/","title":{"rendered":"Bizarre Minion-like creature with no anus is not our earliest known ancestor after all"},"content":{"rendered":"

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By Jason Goodyer\n \t\t<\/p>

Published: Wednesday, 17 August 2022 at 12:00 am<\/p>

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The Saccorhytus<\/em>, a tiny, spikey sack with a large mouth and no anus is not your great many times over grandparent, an international team of researchers has found.<\/p>\n

Previous studies had interpreted the holes that surround Saccorhytus<\/em>\u2019 mouth as being pores for gills and concluded that it was a deuterostome \u2013 a primitive group of animals from which ancient human ancestors emerged.<\/p>\n

However, a new analysis of the 500-million-year-old fossils, which consisted of the piecing together of 100s of X-ray images, has discovered that the holes were in fact caused by spines that broke away as the fossils were preserved.<\/p>\n

\u201cFossils can be quite difficult to interpret and\u00a0Saccorhytus<\/em>\u00a0is no exception. We had to use a synchrotron, a type of particle accelerator, as the basis for our analysis of the fossils,\u201d said the study\u2019s co-author Emily Carlisle<\/a>\u00a0from the\u00a0University of Bristol\u2019s\u00a0School of Earth Sciences.<\/p>\n

\u201cThe synchrotron provides very intense X-Rays that can be used to take detailed images of the fossils. We took hundreds of X-Ray images at slightly different angles and used a supercomputer to create a 3D digital model of the fossils, which reveals the tiny features of its internal and external structures.\u201d<\/p>\n

The researchers then compared the anatomical features of\u00a0Saccorhytus<\/em> to creatures on other evolutionary<\/a> branches of the tree of life and concluded that it was most likely an ecdysoszoan \u2013 a group of creepy crawlies that contains arthropods and nematodes.<\/p>\n

\u201cWe considered lots of alternative groups that\u00a0Saccorhytus<\/em>\u00a0might be related to, including the corals, anemones and jellyfish which also have a mouth but no anus,\u201d said the study\u2019s co-leader\u00a0Prof Philip Donoghue<\/a> of the University of Bristol\u2019s School of Earth Sciences.<\/p>\n

\u201cTo resolve the problem, our computational analysis compared the anatomy of\u00a0Saccorhytus<\/em>\u00a0with all other living groups of animals, concluding a relationship with the arthropods and their kin, the group to which insects, crabs and roundworms belong.\u201d<\/p>\n