

The Common Descent Podcast
Common Descent
Join David and Will as they explore the paleontologists’ perspective on various topics in life and earth history.
Each episode features a main discussion on a topic requested by the listeners, presented as a lighthearted and educational conversation about fossils, evolution, deep time, and more.
Before the main discussion, each episode also includes a news segment, covering recent research related to paleontology and evolution.
Each episode ends with the answer to a question submitted by subscribers on Patreon.
New episodes with new topics every fortnight!
Each episode features a main discussion on a topic requested by the listeners, presented as a lighthearted and educational conversation about fossils, evolution, deep time, and more.
Before the main discussion, each episode also includes a news segment, covering recent research related to paleontology and evolution.
Each episode ends with the answer to a question submitted by subscribers on Patreon.
New episodes with new topics every fortnight!
Episodes
Mentioned books

Sep 14, 2025 • 2h 5min
Episode 226 - Dodos
Dodos are probably the single most famous case of recent human-induced extinction. First documented in the late 1500s and extinct within a century, dodos have become a global reminder of the devastating potential of human activity. This episode, we review the brief history of human interactions with dodos, and we explore what recent research and fossil evidence has taught us about these birds and their closest relatives.
In the news: Cretaceous crocs, extra-spiky dinosaurs, turtles of the sea, and cave fish evolution.
Time markers:
Intro & Announcements: 00:00:00
News: 00:05:45
Main discussion, Part 1: 00:33:10
Main discussion, Part 2: 01:06:00
Patron question: 01:56:50
Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/
Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast
Subscribe to Curiosity Box using our Affiliate Link: https://www.curiositybox.com/CommonDescent
And get 25% off the first box with code descent25
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

Aug 31, 2025 • 2h 56min
Episode 225 - Forests
Forests are among the most widespread and diverse biomes on our planet. This episode, we’re joined by our favorite paleobotanist, Dr. Aly Baumgartner, to explore what defines a forest, how these habitats function, and how they differ around the globe. Then, we’ll take a trip into the past to discuss how paleontologists study ancient forests and how these biomes have changed over hundreds of millions of years.
In the news: ocean sediments, early penguins, island foxes, Canadian dragonflies, and ancient deer.
Time markers:
Intro & Announcements: 00:00:00
News: 00:06:00
Main discussion, Part 1: 00:37:30
Main discussion, Part 2: 01:47:10
Patron question: 02:48:35
Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/
Listen to more Plants with Aly on Leaf it to Us!
https://commondescentpodcast.com/leaf-it-to-us/
Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast
Subscribe to Curiosity Box using our Affiliate Link: https://www.curiositybox.com/CommonDescent
And get 25% off the first box with code descent25
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

Aug 17, 2025 • 2h 15min
Episode 224 - Bipedalism
Most vertebrate animals on land get around on all fours, but some of us have committed to two-legged locomotion. This episode, we explore the various ways animals have evolved bipedalism and the many benefits that come with it. We’ll also take a look at how we identify bipedal animals in the fossil record, and we’ll zoom in on the evolutionary story behind Earth history’s most successful bipeds.
In the news: potato origins, trilobite legs, bone worm burrows, and australopithecine sexes.
Time markers:
Intro & Announcements: 00:00:00
News: 00:07:35
Main discussion, Part 1: 00:35:15
Main discussion, Part 2: 01:10:50
Patron question: 02:05:55
Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/
Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast
Subscribe to Curiosity Box using our Affiliate Link: https://www.curiositybox.com/CommonDescent
And get 25% off the first box with code descent25
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

86 snips
Aug 3, 2025 • 2h 39min
Episode 223 - Mutations
Discover the fascinating world of mutations, the driving force behind evolution and genetic diversity. The hosts dive into how these changes occur and their impact on species, using engaging examples like lactose tolerance and antibiotic resistance. They also explore Neanderthal tools and their surprising complexities, alongside recent findings in dinosaur behavior through unique footprints. Unravel the myths surrounding mutations, their role in health, and how nature delicately balances beneficial and harmful changes.

Jul 20, 2025 • 2h 21min
Episode 222 - Shrews
On the outside, shrews might seem like standard tiny mammals, but their anatomy and lifestyle are highly specialized. This episode, with help from special guest Derek den Ouden, we explore the diverse habits of shrews, the anatomical features that set them apart, and how they thrive worldwide despite being perpetually on the brink of starvation. Then, we consider the extinct diversity of shrews in the fossil record.
In the news: stubborn bass, choking fish, tomato defenses, and some really old rocks.
Time markers:
Intro & Announcements: 00:00:00
News: 00:09:35
Main discussion, Part 1: 00:45:25
Main discussion, Part 2: 01:40:50
Patron question: 02:12:35
Find Derek online at @DenoudenDerek
Check out our website for this episode’s blog post and more: http://commondescentpodcast.com/
Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast
Check out our friends’ new data management app, Cnidarity: https://cnidarity.com/
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

Jul 6, 2025 • 2h 30min
Episode 221 - Legless Lizards
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/
Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast
Happy Disability Pride Month!
AmeriDisability https://www.ameridisability.com/
National Disability Rights Network https://www.ndrn.org/
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

Jun 22, 2025 • 2h 28min
Episode 220 - Terrestrial Crocs
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/
Join us on Patreon to support the podcast and enjoy bonus content: 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

Jun 8, 2025 • 1h 49min
Episode 219 - Beringia
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/
Join us on Patreon to support the podcast and enjoy bonus content: https://www.patreon.com/commondescentpodcast
Some LGBTQIA+ organizations in the southeast US:
Trans Aid Nashville: https://www.transaidnashville.org/
Out Memphis: https://www.outmemphis.org/
Southerners on New Ground: https://southernersonnewground.org
Shoutout to Vic Michaelis for these links: www.instagram.com/vicmmic/
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

May 25, 2025 • 2h 15min
Episode 218 - Lungs
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/
Listen to our new podcast, Leaf it to Us!
https://linktr.ee/leafittouspod
Join us on Patreon to support the podcast and enjoy bonus content: 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

May 11, 2025 • 2h 24min
Episode 217 - Bears
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/
Listen to our new podcast, Leaf it to Us!
https://linktr.ee/leafittouspod
Join us on Patreon to support the podcast and enjoy bonus content: 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