SciShow: Atavisms: 4 Lost Traits That Returned

Teacher or professor: SciShow
Subject: Science
Content of the Lesson: Every once in a while, traits thought to be lost forever suddenly reappear, like a dolphin or a whale born with complete hind limbs! Known as atavisms, these occurrences can teach us all sorts of things, like how limbs actually grow. Hosted by: Hank Green SciShow has a spinoff podcast! It's called SciShow Tangents. Check it out at http://www.scishowtangents.org ---------- Support SciShow by becoming a patron on Patreon: https://www.patreon.com/scishow ---------- Huge thanks go to the following Patreon supporters for helping us keep SciShow free for everyone forever: Kevin Bealer, Jacob, Katie Marie Magnone, D.A. Noe, Charles Southerland, Eric Jensen, Christopher R Boucher, Alex Hackman, Matt Curls, Adam Brainard, Jeffrey McKishen, Scott Satovsky Jr, James Knight, Sam Buck, Chris Peters, Kevin Carpentier, Patrick D. Ashmore, Piya Shedden, Sam Lutfi, Charles George, Christoph Schwanke, Greg ---------- Looking for SciShow elsewhere on the internet? Facebook: http://www.facebook.com/scishow Twitter: http://www.twitter.com/scishow Tumblr: http://scishow.tumblr.com Instagram: http://instagram.com/thescishow ---------- Sources: Dollo’s Law/Atavisms https://pubmed.ncbi.nlm.nih.gov/7991619/ https://doi.org/10.1016/j.tree.2008.06.013 https://doi.org/10.1002/ajmg.a.36234 Cetacean Hind Limbs https://doi.org/10.1007/978-1-4899-0159-0_10 https://doi.org/10.1073/pnas.0602920103 https://doi.org/10.1046/j.1525-142X.2002.02033.x Limpet Shell Twists https://pubmed.ncbi.nlm.nih.gov/16701270/ https://doi.org/10.1098/rspb.2003.2517 Soil Mite Sex https://doi.org/10.1073/pnas.0700034104 https://doi.org/10.1002/ece3.5303 https://doi.org/10.1016/0305-1978(92)90056-J Big Bone Worm Males https://doi.org/10.1016/j.cub.2014.11.032 https://doi.org/10.1016/j.crvi.2008.10.007 https://doi.org/10.1038/s41467-017-01002-8 https://doi.org/10.1186/1741-7007-7-74 Images: https://commons.wikimedia.org/wiki/File:Anthracotherium_magnum.jpg https://link.springer.com/article/10.1007/s12052-009-0135-2/figures/24 https://link.springer.com/article/10.1007/s12052-009-0135-2/figures/2 https://commons.wikimedia.org/wiki/File:Trochita_trochiformis_01.JPG https://www.inaturalist.org/observations/19706160 https://www.inaturalist.org/observations/35191166 https://www.inaturalist.org/observations/32780129 https://www.inaturalist.org/observations/7073348 https://www.flickr.com/photos/jsjgeology/25447477923 https://www.flickr.com/photos/treegrow/31682185476 https://eol.org/media/6248881 https://www.flickr.com/photos/treegrow/39096881684 https://www.flickr.com/photos/treegrow/26010907628 https://www.flickr.com/photos/scrippsocean/15806618219/in/album-72157647375239253/ https://www.flickr.com/photos/scrippsocean/15806619019/in/album-72157647375239253/ https://www.flickr.com/photos/scrippsocean/15372997583/in/album-72157647375239253/


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