Check the fingers and toes of your favorite vertebrate animals and you’re likely to find claws or something similar at the ends. These digit-caps come in a variety of shapes – claws, nails, even hooves – for a variety of functions. In this episode, we discuss the close relationship between claw form and function, how we study claws in the fossil record, and the intriguing questions of how claws came to be as we know them today.

In the news: swimming temnospondyls, ants and plants, Troodon eggs, and cooked snails.

Time markers: Intro & Announcements: 00:00:00 News: 00:05:30 Main discussion, Part 1: 00:38:15 Main discussion, Part 2: 01:17:45 Patron question: 01:45:45

Listen to us on I Know Dino! https://iknowdino.com/sinotyrannus-episode-437/

Will was a guest on Sprites of Life! https://open.spotify.com/episode/7KmiNQcKWgpT6Nn0FRrMMp

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

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You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

You’re probably familiar with frogs and salamanders, but there is a third group of modern amphibians, the strangest of them all: the worm-like caecilians. In this episode, we’ll explore the many bizarre anatomical features of caecilians, from their tentacled faces to their abrupt hind ends. Then we’ll explore the entire caecilian fossil record (it won’t take long) and tackle the much-discussed mystery of how this fascinating lineage of amphibians got started.

In the news: weird marsupial eyes, long dinosaur necks, and kangaroo rats. Also a retraction!

Time markers: Intro & Announcements: 00:00:00 News: 00:05:00 Main discussion, Part 1: 00:43:30 Main discussion, Part 2: 01:22:30 Patron question: 01:59:30

HUGE THANKS to our News guests, Sabrina and Garret! Check out I Know Dino: https://iknowdino.com/ And they have a Patreon! https://www.patreon.com/iknowdino

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

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You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

We spend a huge portion of our lives sleeping. For us and other animals, it’s clearly a very important behavior. And yet, despite how familiar and commonplace it is, there’s plenty we still don’t understand about sleep: its origins, evolution, and even how to define it in the first place. In this episode, we explore some of the remarkable variation in animal sleeping habits, we discuss some of the ways we study and understand sleep, and we touch upon the crucial – and much debated – question of what sleep even does for us anyway.

In the news: early monotremes, chunky dunk, Permian pollinators, and parasitic ant mutations.

Time markers: Intro & Announcements: 00:00:00 News: 00:05:00 Main discussion, Part 1: 00:40:00 Main discussion, Part 2: 01:20:30 Patron question: 02:16:00

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

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Join the Common Descent Discord server! https://discord.gg/CwPBxdh9Ev

Follow and Support us on: Twitter: https://twitter.com/CommonDescentPC Facebook: https://www.facebook.com/commondescentpodcast Instagram: @commondescentpodcast YouTube: https://www.youtube.com/channel/UCePRXHEnZmTGum2r1l2mduw PodBean: https://commondescentpodcast.podbean.com/ iTunes: https://itunes.apple.com/us/podcast/the-common-descent-podcast/id1207586509?mt=2

You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

Once, it was a volcanic crater. Then, it was a lake, perhaps equal parts lush and deadly. Much later, it was a mining site. And finally, today, it is a UNESCO World Heritage Site and one of the most famous and heavily studied fossil sites in the world. In this episode, we discuss the history and formation of the Messel Pit, and we ooh and aah over a small sampling of the many thousands of incredible fossils that have been found there.

In the news: lacewing larvae, folding leaves, dinosaur growth, and ankylosaur sounds.

Time markers: Intro & Announcements: 00:00:00 News: 00:06:00 Main discussion, Part 1: 00:36:00 Main discussion, Part 2: 01:00:00 Patron question: 01:40:30

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

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Find merch at the Common Descent Store! http://zazzle.com/common_descent

Join the Common Descent Discord server! https://discord.gg/CwPBxdh9Ev

Follow and Support us on: Twitter: https://twitter.com/CommonDescentPC Facebook: https://www.facebook.com/commondescentpodcast Instagram: @commondescentpodcast YouTube: https://www.youtube.com/channel/UCePRXHEnZmTGum2r1l2mduw PodBean: https://commondescentpodcast.podbean.com/ iTunes: https://itunes.apple.com/us/podcast/the-common-descent-podcast/id1207586509?mt=2

You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

Giraffes are so famous and familiar to most of us that it can be easy to forget how utterly strange they are. This episode, we explore modern giraffes, their living cousins (okapis!), and their ancient relatives to understand how these monumental mammals came to be how they are. Along the way, we’ll meet a whole variety of wacky-horned fossil species, and we’ll tackle the questions of how and why the giraffe got its long neck.

In the news: dinosaur feet, marine crocs, hunted giant elephants, and bird egg evolution.

Time markers: Intro & Announcements: 00:00:00 News: 00:03:30 Main discussion, Part 1: 00:40:00 Main discussion, Part 2: 01:26:30 Patron question: 02:00:00

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

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You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

Happy Darwin Day!

You’ve seen his artwork. And if you somehow haven’t, you’ve seen lots of art inspired by his artwork. Charles R. Knight might be the most influential paleoartist of all time, inspiring a century’s worth of artists, scientists, and ancient-animal-enthusiasts around the world with his skillful and scientifically-informed works. In this episode, we explore who Knight was, how he became a renowned paleoartist, and his extraordinary role in ushering in the modern world of paleontology.

In the news: Arctic primate-cousins, oldest caecilians, diving bird evolution, and Jehol bird preservation.

Time markers: Intro & Announcements: 00:00:00 News: 00:05:00 Main discussion, Part 1: 00:39:00 Main discussion, Part 2: 01:05:00 Patron question: 01:46:00

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Check out Discovering Us from the Leakey Foundation: https://leakeyfoundation.org/discovering-us/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast

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You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

Glowing organisms might seem like something out of science fiction, but not only do they exist here on Earth, they are incredibly common. Some species glow when exposed to certain kinds of light, and others produce their very own light in the darkest habitats on the planet. This episode, we explore glowing life: how they do it, what they use it for, and what we can tell about how this remarkable ability came to be.

In the news: painted turtles, dinosaur herbivores, human brains, and insect ears.

Time markers: Intro & Announcements: 00:00:00 News: 00:04:30 Main discussion, Part 1: 00:37:00 Main discussion, Part 2: 01:29:00 Patron question: 02:10:30

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast 

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

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Find merch at the Common Descent Store! http://zazzle.com/common_descent

Join the Common Descent Discord server! https://discord.gg/CwPBxdh9Ev

Follow and Support us on: Twitter: https://twitter.com/CommonDescentPC Facebook: https://www.facebook.com/commondescentpodcast Instagram: @commondescentpodcast YouTube: https://www.youtube.com/channel/UCePRXHEnZmTGum2r1l2mduw PodBean: https://commondescentpodcast.podbean.com/ iTunes: https://itunes.apple.com/us/podcast/the-common-descent-podcast/id1207586509?mt=2

You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

The Paleozoic Era was home to many strange and fascinating extinct groups, and among the most eye-catching of these were the eurypterids. Colloquially called “sea scorpions,” these carnivorous aquatic arthropods came in many forms for many habitats and are now known from many amazing fossils. In this episode, we discuss what makes eurypterids distinct from similar organisms, what we know about their lifestyles, and the many ways they continue to surprise and confuse us.

In the news: Brazilian crocs, injured cats, breeding ichthyosaurs, and mammal-munching dinos.

Time markers: Intro & Announcements: 00:00:00 News: 00:05:30 Main discussion, Part 1: 00:40:00 Main discussion, Part 2: 01:03:30 Patron question: 01:48:30

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast 

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

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Join the Common Descent Discord server! https://discord.gg/CwPBxdh9Ev

Follow and Support us on: Twitter: https://twitter.com/CommonDescentPC Facebook: https://www.facebook.com/commondescentpodcast Instagram: @commondescentpodcast YouTube: https://www.youtube.com/channel/UCePRXHEnZmTGum2r1l2mduw PodBean: https://commondescentpodcast.podbean.com/ iTunes: https://itunes.apple.com/us/podcast/the-common-descent-podcast/id1207586509?mt=2

You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/

Happy New Year!

It’s been an exciting and eventful year for the podcast, and we’re glad you’ve been along for the ride! As usual, this is our annual Q&A where we answer the many, many questions our listeners submitted – the scientific, the silly, and the personal.

Thanks as always to all of our listeners, our Patrons, our special guests, and to everyone who supports the podcast in ways big and small.

See you next year.

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast 

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You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

The Intro and Outro music is “On the Origin of Species” by Protodome. More music like this at http://ocremix.org.

It’s a great time of year to talk about conifers! Also their cousins: cycads, ginkgos, and others! Gymnosperms don’t get nearly as much love and attention as their flowering counterparts, the inescapable angiosperms, but they nonetheless have their own fascinating history going all the way back to some of the earliest forests on Earth. This episode, we’re joined once again by our favorite paleobotanist Dr. Aly Baumgartner to discuss what makes gymnosperms unique, what has made them so successful for hundreds of millions of years, and how these incredible plants have changed the world.

In the news: fossil-finding robots, super-old DNA, ankylosaur clubs, and snake sex organs.

Time markers: Intro & Announcements: 00:00:00 News: 00:06:45 Main discussion, Part 1: 00:41:30 Main discussion, Part 2: 01:38:30 Patron question: 02:36:30

Check out our blog for bonus info and pictures: http://commondescentpodcast.com/

Join us on Patreon to support the podcast and enjoy bonus content! https://www.patreon.com/commondescentpodcast 

Follow this link for a 30-day free trial to Audible! www.audibletrial.com/CommonDescent

Or make a one-time donation via PayPal: https://tinyurl.com/4c68u4hp

Find merch at the Common Descent Store! http://zazzle.com/common_descent

Join the Common Descent Discord server! https://discord.gg/CwPBxdh9Ev

Follow and Support us on: Twitter: https://twitter.com/CommonDescentPC Facebook: https://www.facebook.com/commondescentpodcast Instagram: @commondescentpodcast YouTube: https://www.youtube.com/channel/UCePRXHEnZmTGum2r1l2mduw PodBean: https://commondescentpodcast.podbean.com/ iTunes: https://itunes.apple.com/us/podcast/the-common-descent-podcast/id1207586509?mt=2

You can email us at commondescentpodcast(at)gmail.com Or send us physical mail at: The Common Descent Podcast 1735 W State of Franklin Rd. Ste 5 #165 Johnson City, TN 37604

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/