The Common Descent Podcast

Lizards are extremely good at becoming snake-shaped. A long body with small or absent limbs is a shape that has evolved dozens of times across nearly every major lineage of lizards. This episode, we explore the diversity of leglessness in lizards, we discuss which groups have done it and which groups have done it best, and we examine what’s known about the repeated evolution of this unexpected body shape. In the news: giant dusky salamander, very early footprints, a Denisovan skull, a mammoth tusk boomerang, and night lizards. Time markers: Intro & Announcements: 00:00:00 News: 00:06:25 Main discussion, Part 1: 00:41:50 Main discussion, Part 2: 01:33:55 Patron question: 02:16:35 Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/ [http://commondescentpodcast.com/] Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast [https://www.patreon.com/commondescentpodcast] Happy Disability Pride Month! AmeriDisability https://www.ameridisability.com/ [https://www.ameridisability.com/] National Disability Rights Network https://www.ndrn.org/ [https://www.ndrn.org/] Got a topic you want to hear about? Submit your episode request here: https://commondescentpodcast.com/request-a-topic/ [https://commondescentpodcast.com/request-a-topic/] Lots more ways to connect with us: https://linktr.ee/common_descent The Intro and Outro music is “On the Origin of Species” by Protodome. More music like this at http://ocremix.org [http://ocremix.org] Musical Interludes are "Professor Umlaut" by Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0 [http://creativecommons.org/licenses/by/3.0]

Today’s crocs are iconic semi-aquatic predators, but their extended family tree features lots of land-dwelling cousins. This episode, we take a tour through croc evolutionary history and explore the many times these reptiles have taken to life on dry land. We’ll examine what features these terrestrial crocs shared, which ones they didn’t, and what their fossils tell us about how the shape of crocs has changed over time. In the news: sauropod guts, Australian biomarkers, butterfly scales, and tropical archosaurs. Time markers: Intro & Announcements: 00:00:00 News: 00:07:25 Main discussion, Part 1: 00:44:20 Main discussion, Part 2: 01:23:20 Patron question: 02:17:25 Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/ [http://commondescentpodcast.com/] Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast [https://www.patreon.com/commondescentpodcast] Got a topic you want to hear about? Submit your episode request here: https://commondescentpodcast.com/request-a-topic/ [https://commondescentpodcast.com/request-a-topic/] Lots more ways to connect with us: https://linktr.ee/common_descent The Intro and Outro music is “On the Origin of Species” by Protodome. More music like this at http://ocremix.org [http://ocremix.org] Musical Interludes are "Professor Umlaut" by Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0 [http://creativecommons.org/licenses/by/3.0]

For over 100 million years, North America and Asia have been connected over the Pacific Ocean through a region called Beringia. The comings and going of plants and animals across this connection have shaped ecosystems of the past and present. This episode, we explore the geologic history of the region and which ancient species have managed to live in and move through Beringia. In the news: early sperm whales, BC plesiosaurs, megatooth shark food, and Arctic nesting birds. Time markers: Intro & Announcements: 00:00:00 News: 00:09:10 Main discussion, Part 1: 00:35:25 Main discussion, Part 2: 01:02:15 Patron question: 01:40:40 Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/ [http://commondescentpodcast.com/] Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast [https://www.patreon.com/commondescentpodcast] Some LGBTQIA+ organizations in the southeast US: Trans Aid Nashville: https://www.transaidnashville.org/ [https://www.transaidnashville.org/] Out Memphis: https://www.outmemphis.org/ [https://www.outmemphis.org/] Southerners on New Ground: https://southernersonnewground.org [https://southernersonnewground.org] Shoutout to Vic Michaelis for these links: www.instagram.com/vicmmic/ [http://www.instagram.com/vicmmic/] Got a topic you want to hear about? Submit your episode request here: https://commondescentpodcast.com/request-a-topic/ [https://commondescentpodcast.com/request-a-topic/] Lots more ways to connect with us: https://linktr.ee/common_descent The Intro and Outro music is “On the Origin of Species” by Protodome. More music like this at http://ocremix.org [http://ocremix.org] Musical Interludes are "Professor Umlaut" by Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0 [http://creativecommons.org/licenses/by/3.0]

Take a deep breath and appreciate for a moment the organs that let you do it so efficiently. Lungs are an invaluable tool for life out of the water, and are therefore a favorite topic for paleontologists interested in early animals on land. This episode, we explore the diversity of modern lungs and the few but fascinating insights we have into the lungs of ancient animals, from dinosaurs to the first terrestrial vertebrates. In the news: trilobite sizes, polar forests, early footprints, and cicadas. Time markers: Intro & Announcements: 00:00:00 News: 00:05:50 Main discussion, Part 1: 00:31:30 Main discussion, Part 2: 01:21:35 Patron question: 02:05:35 Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/ [http://commondescentpodcast.com/] Listen to our new podcast, Leaf it to Us! https://linktr.ee/leafittouspod [https://linktr.ee/leafittouspod] Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast [https://www.patreon.com/commondescentpodcast] Got a topic you want to hear about? Submit your episode request here: https://commondescentpodcast.com/request-a-topic/ [https://commondescentpodcast.com/request-a-topic/] Lots more ways to connect with us: https://linktr.ee/common_descent The Intro and Outro music is “On the Origin of Species” by Protodome. More music like this at http://ocremix.org [http://ocremix.org] Musical Interludes are "Professor Umlaut" by Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0 [http://creativecommons.org/licenses/by/3.0]

Bears are among the most charismatic and impressive mammals. They have large bodies, very flexible lifestyles, and an extensive fossil record that includes some of the best-preserved and largest fossil mammals of all time. This episode, we explore what makes bears so distinctive and successful, and how their diversity has changed over time. In the news: ancient alligators, rattlesnake venom, late land crocs, pterosaur tracks, and Caribbean crocodiles. Time markers: Intro & Announcements: 00:00:00 News: 00:05:45 Main discussion, Part 1: 00:43:25 Main discussion, Part 2: 01:28:25 Patron question: 02:12:25 Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/ [http://commondescentpodcast.com/] Listen to our new podcast, Leaf it to Us! https://linktr.ee/leafittouspod [https://linktr.ee/leafittouspod] Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast [https://www.patreon.com/commondescentpodcast] Got a topic you want to hear about? Submit your episode request here: https://commondescentpodcast.com/request-a-topic/ Lots more ways to connect with us: https://linktr.ee/common_descent The Intro and Outro music is “On the Origin of Species” by Protodome. More music like this at http://ocremix.org Musical Interludes are "Professor Umlaut" by Kevin MacLeod (incompetech.com). Licensed under Creative Commons: By Attribution 3.0 http://creativecommons.org/licenses/by/3.0 [http://creativecommons.org/licenses/by/3.0]