The Common Descent Podcast

One hundred episodes is kind of a big deal, so we figured we’d pick a big deal kind of topic, and it doesn’t get much bigger than this. As far as we can tell, all life on Earth is descended from a common ancestry – at some point, at least once, life originated on Earth. But when, where, and how? These are open questions that have been subject to lots of scientific and philosophical discussions and...

Insects must be among the most impressive animals in Earth history. For hundreds of millions of years, they have been some of the most significant animals on land in terms of their abundance, diversity, and ecological impact. Their deep story is marked by evolutionary innovations that weren’t just major events for insects, but major events for the entire planet. This episode, we barely scratch the...

Welcome ... to Spookulative Evolution. It’s October once again and time for Spook-E! Each episode throughout this month, we’re choosing a monster and discussing how it – or something like – might evolve biologically, pulling inspiration from critters of the real world. This month’s theme: sea monsters. This episode, we turn our attention to the creatures whose enticing songs sound over the sea. Ho...

Welcome ... to Spookulative Evolution. It’s October once again and time for Spook-E! Each episode throughout this month, we’re choosing a monster and discussing how it – or something like – might evolve biologically, pulling inspiration from critters of the real world. This month’s theme: sea monsters. This episode, we explore a monster whose name is synonymous with immensity and might. What biolo...

When we study life, past or present, we talk a lot about species, their evolution, their diversity, their extinction, and more. But we don’t often slow down to discuss what we really mean by that. What is a species? How and where do new species arise? It turns out this topic is much more complicated – and controversial! – than it may seem. In this episode, we’ll touch on the basics and discuss why...

Welcome ... to Spookulative Evolution. It’s October once again and time for Spook-E! Each episode throughout this month, we’re choosing a monster and discussing how it – or something like – might evolve biologically, pulling inspiration from critters of the real world. This month’s theme: sea monsters. This episode, we tackle a particularly prevalent body shape among sea monsters. How might evolut...

Welcome ... to Spookulative Evolution. It’s October once again and time for Spook-E! Each episode throughout this month, we’re choosing a monster and discussing how it – or something like – might evolve biologically, pulling inspiration from critters of the real world. This month’s theme: sea monsters. This episode, we discuss one of the most famous fictional sea creatures of all. How might natura...

Okay, that’s not a great title. More accurately, we’re discussing toxins, the substances that organisms produce for chemical defense or attack against each other. Toxins are found in practically all living things, they function as part of immune systems, poisonous defenses, and predatory venom, and they have all sorts of amazing effects from discomfort to death. In this episode, we’ll touch on who...

Marsupials are like alternate-reality mammals. Everything about them, from their skeletons to their reproductive strategies, is just a bit strange – from the perspective of us placental mammals, that is! But you can’t argue with results, and marsupials include some of the most fascinating mammals of the past and present. In this episode, we track the long evolutionary journey that gave the modern...

This episode marks the end of our extinction series, but on the bright side, Aly’s here! Most of the extinction events we discuss are very animal-focused, but the end of the Carboniferous Period featured one of history’s worst plant extinctions. This event wiped out the famous ecosystems of the Carboniferous, reshuffled ecosystems, and ushered in a more familiar world of plants. In this episode, a...

Dogs are among the most diverse and successful mammalian predators on the planet, from widespread wild predators like wolves to the most iconic domestic species of all time in our own homes. This episode, we look at what makes dogs unique, where they got their start, what their fossil history has looked like, and finally how one species ended up being among the most widespread species on Earth. In...

Cats are among the most diverse and successful mammalian predators on the planet, from lions on the savanna to ocelots in the jungle to domestic cats in homes and homepages worldwide. This episode, we look at what makes cats unique, where they got their start, what their fossil history has looked like, and finally how one species ended up being among the most widespread species on Earth. In the ne...

Everybody starts somewhere, and most animals start inside an egg! Eggs are about as old and as varied as animal life itself, and when they show up in the fossil record, they can be very telling. In this episode we discuss what goes inside an egg, what makes them so special and useful, and what we can learn from their patchy fossil record. In the news: early archosaurs, more on Dilophosaurus, Micro...

Roughly nine out of ten living amphibian species are frogs. They’re incredibly diverse and successful, and they have been since the Jurassic Period. But the origins of frogs and their fellow modern amphibians is shrouded in mystery. In this episode, we discuss what makes frogs special, what their fossil record looks like, and what paleontologists know and don’t know about the earliest evolution of...

"Living fossils" aren't really a thing, not the way they're typically talked about anyway, and the term can be a source of debate among scientists and science communicators. In this episode, we talk about how this term is used and why some scientists defend it while others (including us!) aren't fans. In the news: horned gophers, dinosaur eggs, giant eggs, and croc tracks. Time markers: Intro & An...

In the Canadian Rockies of British Columbia sits one of the most important, well-studied, and scientifically influential fossil sites in the world. The Burgess Shale not only provides us a glimpse into the tail end of the Cambrian Explosion, and not only yields tens of thousands of fossil specimens, but also includes some of the most exceptional fossil preservation of any fossil locality anywhere....

In this series, we invite scientists to live Q&As on YouTube, where we discuss topics we’ve covered before on the podcast. This episode, we discussed Conservation Paleontology (Episode 8) with Dr. Rachel Short and Dr. Jeff Martin of Texas A&M University.  You can find the video recording on our YouTube channel: https://www.youtube.com/playlist?list=PLfdiT8Klm_YO04cvDqZ-_O3Iiq0J5GZJz Check out our...

In this series, we invite scientists to live Q&As on YouTube, where we discuss topics we’ve covered before on the podcast. This episode, we discussed Paleopathology (Episode 84) with Laura Emmert of the Gray Fossil Site.  You can also watch the video recording of this Live Chat on our YouTube channel: https://www.youtube.com/playlist?list=PLfdiT8Klm_YO04cvDqZ-_O3Iiq0J5GZJz Check out our blog for b...

Start exploring vertebrate evolution and paleontology, and it won’t be long before you end up on the subject of teeth. These handy structures are enormously significant not only for the history of life, but in the study of it as well. In this episode we discuss what makes a tooth a tooth, how teeth came to be, and we muse at length over the incredible diversity and scientific usefulness of teeth....

In this series, we invite scientists to live Q&As on YouTube, where we discuss topics we’ve covered before on the podcast. This episode, we discussed Turtles with Dr. Steven Jasinski of the State Museum of Pennsylvania. You can find Steven on Twitter at @StevenJasinski. You can also watch the video recording of this Live Chat on our YouTube channel: https://www.youtube.com/playlist?list=PLfdiT8Klm...

From massive Triceratops to tiny Psittacosaurus, few dinosaurs are as famous, charismatic, or commonly preserved as ceratopsians. In this episode, we’ll follow this group’s evolutionary journey from little bipeds to horned behemoths and discuss some of the biggest scientific questions about their history, their identification, and of course their magnificently adorned noggins. In the news: the Tul...

In this series, we invite scientists to live Q&As on YouTube, where we discuss topics we’ve covered before on the podcast. This episode, we discussed Ancient DNA with Dr. Leigha Lynch of Washington University. You can find Leigha on Twitter at @PantheraLeigha. You can also watch the video recording of this Live Chat on our YouTube channel: https://www.youtube.com/playlist?list=PLfdiT8Klm_YO04cvDqZ...

In the South Pacific Ocean, there is a family of islands that have been isolated since the Cretaceous Period. New Zealand – past and present – has been home to some of the most unique and fascinating ecosystems on the planet, from its reptiles to its birds to its plants. This episode, we visit New Zealand and take a trip through the fossil and geology history that made it the wonderful place it is...

We’ve discussed mass extinctions quite a bit on this podcast, and indeed we’ve devoted episode to four out of the famous “Big Five” that shaped life on Earth. This episode, we’re completing the set with the Ordovician mass extinction, the earliest of the five. As usual, we’ll explore what happened, who it happened to, why it happened, and how it left its mark on life on Earth. In the news: ocean c...

There’s a pandemic on, and we and many of our listeners are spending lots of time at home. On the bright side, it’s a good opportunity to watch movies and record Silver Screen Science! So, we’re putting together some new episodes, to keep you – and ourselves – entertained. This episode, we share some thoughts from our long and animal-filled journey through the James Bond films. The Common Descent...