Explore every episode of the podcast Past Time

Of Collective Behavior and Trilobites Reading scientific papers can be a daunting prospect. Even the titles can contain layers of jargon. On Past Time, we work diligently to break down the barriers of science to make the discoveries of science for audiences of all ages. In this episode, we experiment with a new method: breaking […]

PAST TIME RETURNS! After three and a half months of discovering how insanely busy a museum curator can be, I (Adam) am back to past times with a brand new episode of Past Time! Join me on a journey back to the Smithsonian Institution to learn about the whole history of sloths. We’ll also meet RYAN […]

Episode 32 – The Changing Face of Crocodiles INTRODUCTION TO GROWING UP – Every living thing grows up, and this episode of “Past Time” explores the evolution of the growing process. Specifically, we explore the evolution of growth in crocodiles, and how changes to the growing process at the earliest stages of crocodile development help […]

THE FIRST FROGS OF NORTH AMERICA Every discovery we make in natural history happens thanks to specimens. Fossil bones, shells, footprints, coprolites, tissue samples—even field notes and photograms—are the building blocks scientists use to tell the story of life on our planet. On Past Time, we talk a LOT about the contributions of museums and […]

Meeting of the Minds There is no bigger paleontology conference for fans of dinosaurs, prehistoric mammals, birds, fishes, and reptiles than the Society of Vertebrate Paleontology Annual Meeting. The 78th annual meeting just took place this October in Albuquerque, New Mexico, USA and Matt, Adam, and Catherine were in attendance. They learned about a lot […]

Ledumahadi and the first dinosaur giants The sauropod dinosaurs—the classic long-necks—included the largest land animal species that have ever lived. Throughout the Jurassic and Cretaceous, multiple families of sauropods achieved body masses over 50 tons: greater than any modern elephant and even exceeding the colossal indricothere rhinoceroses. Despite their incredible sizes, the sauropod dinosaurs have […]

First Iteration I (Adam) am both proud and nervous to say that this is an atypical Past Time episode, as we’re not talking about a new discovery nor a real scientific topic; it is a recap/review of Jurassic World 2. However, I think it is worth addressing whether or not particular elements of new movies, […]

Eighty million years ago, a wildly ornamented species of horned dinosaur roamed the southern half of North America’s western landmass, Laramidia. In 2016, paleontologist Eric Lund and his colleagues named it Machairoceratops cronusi, and we fell in love with this ceratopsian from Utah with hooks over its frill. In 2017, the site where Machairoceratops was […]

Big bites come in small skulls This episode tells a story of one of Adam Pritchard’s favorite projects from Yale University, describing the skull of a teeny reptile from the early days of the Age of Reptiles. Hailing from the eastern coast of North America (present-day Connecticut), Colobops noviportensis had a skull only an inch […]

Masters of horns and teeth Throughout the Jurassic and Cretaceous Periods, dinosaurs were top dogs on every continent and in every sort of environment. The ceratosaurs were some of the classic predators that ruled the tops of the food chains for much of that time. Including classic predators such as Ceratosaurus, Carnotaurus, and Majungasaurus—as well as oddballs […]

Egyptian paleontology has a long and storied history, although much of it is focused on discoveries from the Cenozoic Era. Incredible fossils of early whales, primates, and other mammals have been discovered in Egypt since the beginning of the twentieth century, work that continues to this day. However, fossils from the Age of Reptiles are […]

This episode was a blast to produce for a vertebrate scientist. I learned a ton about the echinoderms, the group of invertebrate animals to which sea stars, brittle stars, sea cucumbers, sea urchins, and crinoids belong. Be prepared for more adventures with invertebrate animals in the future. Engineering Echinoderms with Elizabeth Clark! This episode would […]

Matheronodon is certainly a dinosaur worthy of a bigger bite. With proportionally giant teeth strikingly different from the standard-issue ornithopod dinosaur, it is certainly one of the most important dino discoveries out of Europe this year. Better yet, the original scientific paper by Pascal Godefroit and colleagues is free to read in the journal Scientific […]

The quest to recover ancient genetic material from extinct animals had its blockbuster moment when Jurassic Park came out. But where did the idea come from and who is trying to figure out if the science fiction of Jurassic Park can be science reality? We talk to Dr. Elizabeth Jones, a science historian at University […]

Hi all. Adam Pritchard here. I’ve been thinking about telling the story of my field experience in the Triassic-aged Chinle Formation of northern New Mexico for many years. The Hayden Quarry fossil site at Ghost Ranch has produced the best-preserved and most diverse record of American dinosaurs from the Triassic of North America, plus some […]

A few weeks ago Past Time co-host Matt Borths published a study that identified a new species of now-extinct carnivorous mammal from Egypt. The animal was near the top of the African food chain when Africa was cut off from the other continents. It lived in the same swampy ecosystem that was home to our earliest […]

Past Time is BACK! Matt and Adam have been traveling the world independently for some time, delving deeply into the history of life on the planet, but now they’re back to tell you all about what they’ve discovered!   In this episode, Matt interviews Adam about his research into the early days of the Age of […]

The relationship between predator and prey is a primal one, and one that fires the curiosity of many fossil fans. We love paintings of Tyrannosaurus battling Triceratops or saber-toothed cats leaping onto the backs of ground sloths. And we can be pretty sure that those interactions happened based on TRACE FOSSILS, like tooth marks in […]

Growth is a universal facet of all organisms that have ever lived, but figuring out how old they grow isn’t always easy. A new study examined the growth in one of the biggest predatory fish in all the ocean, the Greenland Shark (Somniosus microcephalus), revealing it to be the vertebrate species with the longest lifespan: nearly […]

I tried to google “crocodiles are living fossils,” to see just how commonly that expression was used in popular articles. There were indeed a few articles that referenced this idea, suggesting that croc fossils from 80 million years ago would look identical the skeletons they have today. However, most were news stories reporting various discoveries […]

Erik Gorscak and Pat O'Connor, two paleontologists from Ohio University, are about to set out on an expedition to Antarctica to hunt for fossils from the end of the Age of Dinosaurs. They are part of a larger team called the Antarctic Peninsula Paleontology Project (AP3), an international collaboration of fossil hunters and geologists who are about to spend almost two months at the bottom of the planet. Past Time talks to them about how you look for fossils in Antarctic conditions, how you plan an expedition, and what they hope to find. When they get back, we'll check in and see what they found! @antarcticdinos #AP3 @ohiou

If you wander into the basement of the Peabody Museum of Natural History at Yale University, and wander into the fossil collections, you will find a vast array of different dinosaurs dating back over 200 million years. However, just a few feet away from the oldest dinosaurs you will find several drawers filled with the […]

With Past Time, Matt and I tend to focus on the new discoveries in paleontology: the new species that show up in the news, or the important specimens discovered in museum collections. These are the raw materials that feed the fires of paleontology as a science. However, observation is only the first step in the […]

On this episode of Past Time, Drs. Matthew Borths and Adam Pritchard share their dissertation stories, and a bit of advice on the grad school experience!

It weighed twice as much as a modern wolf. It had three pairs of meat-slicing teeth. It was the first carnivorous land animal to reach 200 pounds on the entire continent of Europe after the extinction of the dinosaurs. And a team of European scientists and Past Time co-host Matthew Borths just introduced us to it. Ladies and gentlemen: meet Kerberos, monster mammal carnivore!

Arrr, ye mateys! Pour out some grog, and I’ll tell ye a tale of mines, beaches, and death in ancient jungles. I of course be talkin’…about salamanders! Okay, not going to do that voice the whole time (though maybe it should be in the episode), but I will briefly present Palaeoplethodon hispaniolae, the first salamander […]

The oldest basilisk lizard from North America, described by Jack Conrad from NYIT College of Osteopathic Medicine, shows the 48 million year old animal was part of an ancient lush jungle ecosystem...in the middle of Wyoming. The beautifully preserved skull has important stories to tell about the evolution of the lizards most famous for their ability to scamper across the water, but it also reveals what North America was like during a greenhouse world that wasn't all that different from what our planet's future may look like.

As Jurassic World rolls out, Matt has some thoughts on the scientific impact of Jurassic Park and offers his hopes for the scientific discussions Jurassic World might spark.

Dating fossils might sound like Saturday night for a paleontologist, but it’s serious science! In a new study, a group of physicists and paleontologists teamed up to re-date one of the most complete skeletons of a human relative ever discovered. The skeleton was discovered in a cave in South Africa twenty years ago, but the […]

Brontosaurus was an extinct name for an extinct animal, but a new study brings the “Thunder Lizard” title roaring back to life! But how does a name get dropped, and how does it get brought back again? Follow us into the winding world of paleontology taxonomy, the study of names. In the 1870s two giant hip […]

In a study published in the Proceedings of the Royal Society B, Rodolfo Salas-Gismondi and other paleontontologists described the crocodiles from a gigantic wetland that predated the Amazon. Ten million years ago there was the giant Purussarus, the duck-billed Mourasuchus, the tube-snouted gharial-like croc, a coyote-like croc similar to Paleosuchus, and three new crocs with […]

Under the canopy of an ancient fern forest near the border of Arizona and New Mexico a colossal crocodile-like reptile took a bite out of an even larger, toothy giant. The attack failed and the victim limped on to fight another day, until its carcass was finally pillaged by another scaly monster and smaller, pickier scavengers. Studying bones collected over a century ago, scientists are now able to reconstruct these scenes from the ancient Wild West using new digital tools familiar to fans of C.S.I. Join Matt and Adam as we explore the crazy Triassic world 215 million years ago where a colossal rauisuchian was ambushed by a gigantic phytosaur!

A new fossil shows an ancient reptile, Philydrosaurus, surrounded by young. Possible evidence that parental investment is a more ancient trait in land-based vertebrates than paleontologists thought! Reptiles aren’t known for being great parents. When it comes to time and energy spent with the kids, mammals get all the glory. Birds also spend a lot […]

Researchers lead by Hans-Dieter Sues from the Smithsonian Institution described a wealth of new giant, long-necked dinosaur material from Western Asia (Uzbekistan). They were able to reconstruct what the brain looked like and discvered the dinosaur, part of the lineage called "titanosaurs", is closely related to animals from the far East of Asia, places like China and Laos. They decided there wasn't enough of the giant to give it a name, but they know it and its relatives were able to make a living across the diverse enviroments of Asia 90 million years ago. This is further evidence that tintanosaurs were successful for much of the Age of Dinosaurs both on the Northern and Southern continents. The study: Sues, H.-D., A. Averianov, and R. C. Ridgely, and L. M. Witmer (2015) Titanosauria (Dinosauria, Sauropoda) from the Upper Cretaceous (Turonian) Bissekty Formation of Uzbekistan. Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2014.889145

Iguanodon was discovered before the word "dinosaur" was invented and the story of Iguanodon research is the story of dinosaur research as paleontologists use new fossils to test old ideas about what the animal looked like and how it moved. Was it a lumbering quadruped? A springy kangaroo reptile? A little of both? Join us as we dive into the history of paleontology and the history of Iguanodon, the enthusiastic animal who is always ready to give you two thumbs up!

To conjure up extinct environments, museums, books, and documentaries rely on art to show vanished animals revitalized in their ancient surroundings. This type of educational reconstruction is called Paleoart (or Palaeoart for the UK inclined) and you can't help but look at an image of a roaming Tyrannosaurus rex without wondering, "How much of that is real?" How do we know its bulk, its color, its environment, or its behavior? Where does the science start and the art (and hypothesizing) begin? Julius Csotonyi, a Candian paleoartist, sat down with us to discuss how he assembles his images which are on display in natural history museums across North America and fill his recently published book, The Paleoart of Julius Csotonyi. A single landscape by Julius is a blend of the latest knowledge from paleontologists, zoologists, paleobotanists, geologists, and geochemists, and as new information is learned, he is ready to update his paintings and present the world with a more accurate glimpse into the ancient past.

When we think of paleontologists, we think of people hunkered down with bones, teeth, and shells studying the preserved body parts of dead organisms. But animals leave behind more than just their skeletons. As they walk they can leave behind footprints, as they eat they can leave behind bite marks, and as they finish eating they leave behind…well…what comes from the behind. The study of the traces of past behavior is called ichnology and Dr. Tony Martin (@Ichnologist) and author of “Dinosaurs without Bones” is with us to reveal all the amazing insights a paleontologist can learn from the fossil record, even when there aren’t any bones! He takes us through a wandering heard of sauropod dinosaurs, into the burrow of the dinosaur Oryctodromeus, and across the mudflats of an amphibian-dominated Alabama. These animals may be extinct, but their traces bring them back to thundering life in this episode of Past Time!

When we think of iconic dinosaurs, like T. rex with its massive head full of teeth, and Parasaurolophus crowned with a gigantic, tube-like horn, we’re thinking of the features of adult dinosaurs. But we know from looking around today that animals change a lot from birth to adulthood. Did T. rex always have a massive maw and Parasaurolophus a huge crest? How quickly did they grow in? What were they used for? To really understand the biology of these titans, paleontologists need to study baby dinosaurs to connect the dots from tiny hatchling to adult dinosaur. Unfortunately, the fossils of dino-toddlers are few and far between because their skeletons are usually pretty delicate. In this episode we discuss the improbable discovery of a baby Parasaurolophus with Dr. Andy Farke, a paleontologist from the Raymond Alf Museum and Webb Schools in Clermont, California. Dubbed “Dinosaur Joe”, the young dinosaur was found and studied by young, high school scientists from the Webb School. The high school scientists were part of the team that revealed the six-foot-long animal was only one-year-old and had a little nubbin of a what would become that spectacular Parasaurolophus crest. Listen to the episode to learn more about growing up dinosaur!

Marine mammals are fascinating beasts. Whales, manatees, seals, otters...they've all gone back to the water and in the process evolved all kinds of spectacular adaptations to make a living in a soggy setting. Toothed evolved an ability to “see” the underwater world around them using echolocation - basically sonar - to track prey with high-pitched sounds and echoes. A 23 million years old fossil from South Carolina called Cotylocara shows toothed whales could echolocate early in their evolutionary history. A more surprising adaptation to life in the water was preserved with another new whale fossil from California. Called Semirostrum, the new whale has a huge underbite and long chin which was probably used as a sensitive probe to track down buried prey. Whales in the water are interesting, but not unexpected. Our final study examines how SLOTHS adapted to life in the ocean. Thalassocnus was a relative of giant ground sloths, a solidly terrestrial group of animals. A recent study showed how Thalassocnus gradually acquired thickened bones, a trait that has been observed in nearly every mammal that has gone back to the water. Even if it’s a weird animal to imagine clawing through the water, it adapted to that lifestyle in exactly the way paleontologists expect any mammal to get back to the water!

Over 400 million years ago the oceans were teeming with life, but it didn’t look much like what you see at the aquarium or in Finding Nemo. Instead of colorful fish flitting through coral reefs, the ancient seas had giant, shelled squids darting past the icons of the early ocean: The Trilobites! Journey back to the Late Ordovician sea with Dr. Brenda Hunda, Curator of Invertebrates at the Cincinnati Museum Center. Dr. Hunda has spent her career carefully documenting the changes in trilobites in the remarkable rocks near Cincinnati, Ohio. Trilobites were spectacularly diverse early arthropods (the group that includes crustaceous, insects, and arachnids) that adapted to the ever-changing seas, by swimming through the water, scooting along the ocean floor, and burrowing through the mud for their 300 million year reign. Our journey through the ancient Queen City features the musical talents of two great Cincinnati-area bands: The Cincinnati Dancing Pigs and Jake Speed and the Freddies! Take the plunge into invertebrate paleontology with Matt and Adam in this episode of Past Time!

50 million-years ago, the heir to Tyrannosaurus stalked the forests of ancient Europe and North America, snapping up the tiny ancestors of horses, cows, and wolves in its colossal meat-cleaving beak. Gastornis was a six-foot-tall, flightless bird and the king of the food chain...or that’s what we thought. For decades paleontologists looked at the huge, parrot-like head and thought the giant bird must be a carnivore, but a recent, exhaustive study drew on molecular evidence, anatomical evidence, and ecological evidence to show Gastornis was a giant herbivore! The former terror bird likely used that massive beak to crack open the abundant seeds and leaves that would have littered the forest at the beginning of the Age of Mammals. Tune in to Past Time to learn how the fossil Terror Bird became Big Bird!

Meet Alienochelys selloumi, a giant, snorkel-nosed turtle with powerful, shell-crushing plates in its massive beak! The distant relative of the largest turtle alive today, the leatherback sea turtle, Alienochelys swam the ancient ocean of North Africa at the very end of the Age of Dinosaurs (the Late Cretaceous). It was found in the same rocks as Ocepechelon, the whale turtle discussed in our first Quick Bite back in July. There were a lot of giant, goofy, snorkel-snouted turtles in Cretaceous Morocco! When Alienochelys' discovery was announced, another paper was published describing fossilized pigment molecules that showed many marine reptiles, including a 55 million-year-old leatherback sea turtle, were dark in color, an adaptation we see in many modern swimming vertebrates. It's time to pick a new-favorite fossil turtle with Past Time!

Little people! Giant reptiles! Towering elephants! Huge birds! It sounds like the stuff of literary and box-office gold, but this Middle-Earth-like world actually existed 17,000 years ago on Flores, an island near Indonesia. Homo floresiensis, or "The Hobbts", only stood three feet tall but they cast a huge shadow over the story of human evolution. In 2004 fossils of the small, big-footed hominins were discovered and they have challenged paleoanthropologists, like this episode's Dr. William Jungers, to reconsider many hypotheses of human origins including which species left the continent and how we're all related. Once thought to just be small versions of Homo erectus, the hobbits may have much more ancient ancestors, posing more questions for the fossil record to answer as the human story becomes even more complicated...and interesting!

Last episode we featured Lythronax, the oldest-known North American tyrannosaur and a close relative of Tyrannosaurus rex. But tyrannosaurs weren’t the only big carnivores to tromp through the Mesozoic of North America. Before the tyrant lizards were huge, there was another giant terrorizing the American West: Siats! Named for a Ute mythological giant, Siats was a bus-sized carnivore in the middle Cretaceous of Utah (99 million years ago). The giant had close relatives - the neoventors - on almost all the continents. This is a bit of a mystery because the continents were getting spread out by 99 million years, making it tough to explain how the neovenators conquered the world. In North America, this global dynasty replaced another family of giants: the carcharodontosaurs which included Acrocanthosaurus the top carnivore of the Early Cretaceous of Western and Eastern North America. The discovery of Siats shows different lineages of carnivorous dinosaurs could get really big and T. rex is just the last monarch to fill the giant carnivore niche in North America. It’s another toothy, terrifying tale on Past Time!

Tyrannosaurus rex is a dinosaur celebrity, a villain in most dinosaur movies and documentaries, but where did the massive beast come from? On November 6, 2013, a team of paleontologists including our expert in this episode, Dr. Randy Irmis from the University of Utah and the Natural History Museum of Utah, published two new skeletons of Tyrannosaurus’s close kin: Teratophoneus and Lythronax. The skeletons reveal Tyrannosauridae (T. rex’s family) was diverse 80 million years ago with different species living in different parts of Western North America. The new genus Lythronax is the oldest member of the Tyrannosauridae even though its anatomy closely resembles the last species of tyrannosaurid, T. rex. A massive sea divided Western North America, called Laramidia, from Eastern North America, called Appalachia. Laramidia was a long, skinny continent that ran from Alaska to Baja California. In general, in modern ecosystems, the larger the land-mass, the more species can live on it. Laramidia was one-tenth the size of the continent of North America, but it supported more species of large animals than the complete continent of North America today! Geologists, paleontologists, and ecologists aren’t sure how this was possible so they continue to search for new fossils and the origins of the North American ecosystem. New fossils, like Teratophoneus and Lythronax show us there are still more questions to answer using the fossil record! Sic semper tyrannis!

Fossils are the raw materials of paleontology, but if we want to know how an animal moved or ate, paleontologists, like Dr. Paul Gignac, need to study living animals, too. Dr. Gignac studies crocodylians, measuring their bite forces across species and as they grow up to figure out how the strongest bite in nature evolved. Using techniques drawn from mechanical engineering and physiology, Dr. Gignac discovered the relationship between body size and bite force in crocodiles, and developed equations to calculate those forces. Then he used these equations to calculate the bite forces of giant extinct crocodiles like Deinosuchus. He also studied the bite marks left by the sickle-clawed dinosaur Deinonychus to calculate dinosaur bite forces. There are so many questions to ask about extinct animals but there's also a lot left to learn about their living descendants! The lines between scientific disciplines get blurred and the questions just get more interesting in this episode of Past Time!

Whales are spectacularly specialized mammals that seem perfectly adapted to their marine habitat. Plenty of other mammals have gone back to the water, but whales take it to a whole new level. No back legs, weird ear bones, noses on top of the head. What could the land-based ancestor of whales possibly looked like? Is there a fossil record of walking whales? In this episode we discover whales belong to the hooved animal group called Artiodactlys and their closest relatives, according to molecular comparisons, are hippos! But hippos and extinct fossil whales don't look very much alike. How did paleontologists, like our guest Dr. Marueen O'Leary, figure out the origins of whales, and how will they figure out the origins of hippos? As always, there are always more questions to answer when we start digging into the fossil record!

Mammals were scrambling around during the Age of Dinosaurs and they're usually seen as small, shrew-like animals waiting for their chance to become diverse. But recent research, including three new fossils discovered in 160 million-year-old rocks from China, show our mammalian cousins were ecologically specialized creatures. Arboroharamiya was climbing through the trees while Megaconus scrambled along the ground, and Rugosodon lead the way for the diverse radiation of mammals called Multituberculates. In this episode, Matt tries to show Adam why these new, tiny mammals are so interesting and where they fit into the mammalian tree of life.

The fossil record is pretty patchy. Most discoveries are tooth fragments, chunks of shell, or isolated slivers of bone and paleontologists are trained to eke out as much information from these precious fragments as they can. But some fossil deposits preserve more than just bones and teeth. Called "Lagerstätte" some rare deposites preserve traces of difficult-to-fossilized soft-tissues like feathers and fur. Some even preserve an animal's last meal before it entered the fossil record. In this episode of Past Time, Matt and Adam discuss Messel, a German fossil site that is one of the best examples of the biological and ecological knowledge preserved in these rare Lagerstätten deposits. Early bats, mini horses, and galloping crocodiles once roamed this extinct jungle in the heart of Europe. The exquisite preservation at Messel lets paleontologists travel back to this exotic ecosystem to tease out connections between the beginning of the Age of Mammals and modern tropical environments.