18 minutes | Feb 9, 2020
Episode 34 – March of the Trilobites
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 down every word in the title of a scientific paper. It might seem like a little task, but it is a way to introduce people to big ideas! This time, we introduce big ideas about trilobites! For this episode, we delve into the journal Scientific Reports and the article “Collective behaviour in 480-million-year-old trilobite arthropods from Morocco.” by Jean Vannier of the Université de Lyon and his colleagues. This title doesn’t have a ton of jargon, but it presents a great chance to look at INVERTEBRATE animals…gathering into a conga line. Two examples of Ampyx priscus lines from the Fezouata Shale of Morocco. Image modified from Figure 2 of Vannier et al. (2019). Well, not an actual conga line…but the fossil trilobite fossils in this paper are definitely situated in a single-file lines. These specimens of the species Ampyx priscus come from an amazing fossil deposit in Morocco. They teach us about the anatomy of trilobites, but they preserve important clues about the behaviors of ancient animals. Join us as we learn how and why trilobites—and living invertebrates—gather together in collective behaviors. Dig Deeper… To read the original open-access paper, check out this link! This popular article by LiveScience details the discovery. For a classic Past Time episode about trilobites, check out our interview with paleontologist Brenda Hunda! To learn more about trilobites, check out this laboratory exercise from an undergraduate paleontology course at Kansas University by Drs. Michelle Casey and Bruce Lieberman. To see some modern invertebrate conga lines, join Jacques Cousteau in this classic documentary about the spiny lobster! Conga lines begin around the 33:00 mark.
37 minutes | Nov 25, 2019
Episode 33 – The Story of the Sloth
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 HAUPT, an ally in sloth paleontology and science podcasting! Ryan Haupt: Master of Sloth A Ph. D. candidate at the University of Wyoming, a fellow with the Geological Society of America, a researcher at the Smithsonian Institution, AND a podcaster…Ryan Haupt is a busy guy. His research focuses on the roles of sloths in both ancient and modern ecosystems. Balancing studies of sloth biology in the jungles of Panama and laboratory work on ground sloth bones and teeth, Ryan was the perfect guest to teach us in this episode of Past Time. He might even throw in some sloth coprolites (fossil feces) for the heck of it! Together, Ryan and I explore over thirty million years of sloth history and HOW we know what we know about extinct sloth species. Ryan studied sloths in the jungles of Panama. This photo shows him holding a mother sloth complete with a baby gripping her chest! Science…Sort Of Ryan helps lead the team on the popular science podcast Science…Sort Of! He is one a huge team of ‘paleo-pals’ that produce the series, which focuses on scientists from all fields: from physics to chemistry to geology to biology! Science…Sort Of presents scientific ideas to a broad audience in a free-form conversational format. The series has featured noted science communicators like astrophysicist Neil deGrasse Tyson, science writer Carl Zimmer, and yours truly! But Ryan and his friends what scientists of all backgrounds on the podcast, to get their stories out to the largest possible audience! DIG DEEPER – Science…Sort of. Explore the podcast at their website: https://sciencesortof.com/ Follow them on Facebook and Twitter! If you like what you hear, you can support the podcast on Patreon and receive updates and special rewards! Sloth Conservation and Research Check out the Sloth Conservation Foundation. Ryan is a member of the board for the foundation. Visit your closest museum. If you are in North OR South America, it almost certainly has some fossils of a ground sloth! For the best of ground sloth fossils, visit the American Museum of Natural History (New York, NY). SO MANY SLOTHS! The sloth display at the Hall of Mammals at the American Museum of Natural History includes several giant ground sloths! Photograph by Wikimedia user Dallas Krentzel (CC License 2.0). Click here for a classic Past Time episode featuring Thalassocnus, the sloths that swam in the Pacific Ocean off the coast of Peru. For the episode field guide, click here. Acknowledgments To check out the giant ground sloth model that gave its likeness to our cover image, visit the Virginia Museum of Natural History in Martinsville, Virginia. Jungle background image from Wikimedia user Dirk Vander Made (Creative Commons 1.0 license).
24 minutes | Jul 20, 2019
Episode 32 – The Changing Face of Crocodiles
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 produce the wide array of crocodile snout shapes we see today and in the fossil record. Increase the rate of snout growth in an embryonic croc, and you can produce an adult with a narrow, tubular snout like an Indian gharial or an African slender-snouted crocodile. Slow that process down, and you can produce an adult with a short, rounded snout like a broad-snouted caiman or an African dwarf crocodile. THE QUEST FOR CROCODILE SKULLS – Paleontologist/Developmental biologist Zachary Morris spritzes water over an incubator filled with Alligator eggs. Our guest this week is Zachary Morris, a Ph.D. student at Harvard University who studies growth in crocodylians. He wields both the fossil record and the skeletons of modern crocodylians—from tiny embryos to giant adults—to study that very topic. To examine the shape changes in the skull of crocodylians through the growth process, Zach has traveled the world to collect eggs, embryos, juveniles, and adults to build 3D models of skull anatomy. He delved into the collections of museums around the world to find nests and eggs of rare crocodiles that were collected by explorers hundreds of years ago. Zoos were also a critical resource for eggs of breeding species. DIG DEEPER – Further reading and links – The original paper by Zach and his research team was published in the journal Proceedings of the Royal Society B in Spring 2019. To learn more about Zach and his research, visit his research site. To see all the snout shapes that exist in modern crocodylians and their fossil cousins, check out this amazing review by crocodylian expert Dr. Christopher Brochu. If you’re interested in visiting ALL the crocodylian species in the world, travel to Florida for a visit to the St. Augustine Alligator Farm. It’s not so much a farm as a glorious reptile zoo with a deep dedication to the research and conservation of endangered reptile species. For more information on reproduction in modern crocodylians—from mating rituals to nesting to parenting strategies—the IUCN Crocodylian Specialist Group produced this amazing summary. Media Credits – Image of a hatching baby crocodile from an etching by Heath. Used under CC 4.0 license courtesy of Wellcome Images https://commons.wikimedia.org/wiki/File:A_young_crocodile_hatching_from_the_egg._Etching_by_Heath._Wellcome_V0021210.jpg Image of African Dwarf Crocodile from Wikimedia and a photograph by Charlie Marshall. Used under a CC 2.0 license. https://commons.wikimedia.org/wiki/File:Pygmy_Crocodile_at_Bristol_Zoo_(17987351179).jpg Image of African Slender-Snouted Crocodile from Wikimedia and a photograph by Tim Strater. Used under a CC 2.0 license. https://commons.wikimedia.org/wiki/File:Pantserkrokodil_(14783902910).jpg
12 minutes | May 17, 2019
Episode 31 – The First Frogs of the Age of Dinosaurs!
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 scientists to the story of life. However, we don’t often address the specific specimens that help tell that story. Even one little bone can reveal great truths. A SINGLE SPECIMEN. A BIG DISCOVERY. Meet DMNH 2018-05-0002, an eyelash-sized bone from the 213-million-year-old Chinle Formation of eastern Arizona. The bone is housed in the fossil collections of the Perot Museum of Nature and Science in Dallas, Texas. DMNH 2018-05-0002 (I refuse to abbreviate!) is a right ilium (pelvic bone) of a frog that was likely only a few centimeters long in life. This fragile treasure is the oldest evidence for a frog on the entire North American continent, predating the next fossil by 30 million years! One little bone leads to a huge expansion in the story of frogs, the most abundant group of amphibians on Earth! Dr. Michelle Stocker holds up DMNH 2018-05-0002 embedded in matrix and wax. It’s THAT small. Image from vt.edu These amazing frogs were published in Biology Letters by Virginia Tech paleontologist Michelle Stocker, a world-renowned expert on Triassic ecosystems. Dr. Stocker and her team have done a lot of recent work on MICROVERTEBRATES, the bones and teeth of tiny animals. Microvertebrate fossil sites are those that preserve large quantities of tiny (~1 centimeter and smaller) bits, and they can tell us a lot about the smaller animals in an environment. Some paleontologists use sifting and fine-mesh screens to collect bones out of these sediments. In this case, Dr. Stocker and her team prepared bones out of blocks of sediment using microscopes and extremely fine tools. Hat-tip specifically to Ben Kligman, a Virginia Ph.D. student who is pioneering these refined preparation techniques! Images of the Chinle frog fossils described by Stocker et al. (2019). DMNH 2018-05-0002 is featured in the top row. The lower images include other frog ilia and jaw fragments found in the collections of Petrified Forest National Park and the Museum of Northern Arizona. DIG DEEPER (Links and Reading) The Perot Museum of Nature and Science in Dallas, Texas is a world-class museum with incredible collections of Cretaceous vertebrates from Texas, Alaska, and across the western United States. Obviously, there are some Triassic treasures in the collection, too! The exhibits include classic American dinosaurs like Alamosaurus, Tyrannosaurus, and Tenontosaurus and some newcomers like Convolosaurus, Nanuqsaurus, and Ugrunaaluk. The original scientific paper in Biology Letters by Dr. Michelle Stocker and her colleagues describes the Chinle frogs, including DMNH 2018-05-0002 and a series of other tiny frog fragments from Triassic Arizona. For general audiences, Virginia Tech put out a press release describing the discovery, including a video featuring Dr. Stocker. Petrified Forest National Park (PEFO) is an amazing park in eastern Arizona. Named for the fossilized remains of ancient forests from the Triassic Period, PEFO contains some of the largest fossil exposures from the Triassic Period of North America. DMNH 2018-05-0002 was found just to the south of the park, but some additional Triassic frog bits have been found in the PEFO fossil collections! Seriously, go to PEFO if you like beautiful and desolate vistas! VT Paleobiology is a collaborative effort of all of the Virginia Tech paleontologists, including Dr. Stocker. Their research ranges from Cambrian invertebrates, to Triassic ecosystems, to Cretaceous tyrannosaurs, and beyond! ACKNOWLEDGMENTS The amazing artwork used for the promo image is a painting by paleo-artist Andrey Atuchin commissioned for this study. Check out his artwork at Deviantart and Twitter! Frog sound effects from freesound.org user flapknot.
27 minutes | Dec 13, 2018
Episode 30 – SVP Recap, guest-starring I KNOW DINO
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 of exciting new discoveries in natural history, and they also made friends with another pair of paleo-podcasters: Garrett and Sabrina of I Know Dino! Dig Deeper For more about the SVP meeting, visit the society website at www.vertpaleo.org. Anyone can attend, provided they register for the meeting. To learn more about (and subscribe to!) I Know Dino, check out their official website at www.iknowdino.com. You can subscribe to their podcast on iTunes, like them on Facebook, and follow them on Twitter! To read all about real dinosaur lungs, you can read the original paper by Xiaoli Wang and colleagues in the journal Proceedings of the National Academy of Sciences! Be sure to subscribe to Past Time on iTunes, follow us on Twitter, like us on Facebook, and subscribe to our revitalized YouTube channel!
12 minutes | Oct 4, 2018
Episode 29 – First of the Four-Footed Giant Dinosaurs!
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 a murky early history… This Past Time episode features a brand new species of sauropod cousin from the Early Jurassic of South Africa: Ledumahadi mafube. Described in a new paper in the journal Current Biology, Ledumahadi is part of a group of dinosaurs traditionally called “prosauropods.” Unlike the straight, column-like legs of true sauropods, Ledumahadi has strong but flexed arms and legs that lacked weight-bearing adaptations of its later cousin. Despite these anatomical differences, this new colossus achieved a mass over 12 tons, upending our classic understanding of the evolution of gigantic size! REFERENCES The original paper on Ledumahaadi mafube was published in the journal Current Biology and is available at this link. The University of the Witwatersrand put out a great press release and Youtube video about this awesome find, so check those out too! For more great research on the early days of the giants, check out lead author Dr. Blair McPhee’s research profile. To check out some great sauropod cousin specimens, check out the specimens on display at the Evolutionary Studies Institute in Johannesburg, South Africa. For more general information on sauropod cousins and the true sauropods, I recommend Dr. Tom Holtz’s overview of the group on his University of Maryland website. You can also check out a classic Past Time episode on growth in the super-giant sauropods featuring friend of the show Dr. Mike D’Emic. The awesome art used for our promo image is work by Viktor Radermache, an up-and-coming paleoartist who has also worked on other finds out of the Evolutionary Studies Institute. Check out this cool interview with him for some more science and artwork. I added myself to the artwork in the front under Creative Commons 4.0. Sound effects from this episode are used under Creative Commons 3.0 licenses and were produced by AlexTriceratops123 (‘Elephant Growls’), Souchav (‘kid-playing-in-a-swimming-pool’), sonicport (‘stream6’), and maj061785 (‘stomp.’). These are available through freesound.org.
50 minutes | Aug 21, 2018
Episode 28 – PAST TIME reviews Jurassic World Fallen Kingdom!
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, television, or books adhere to modern science. Dr. Elizabeth Jones taught us that science fiction can have a major impact on scientific advances, as Jurassic Park helped give rise to modern techniques that revealed all sorts of molecules in ancient fossil remains. Although it is far less…science-y…than the original Jurassic Park, Jurassic World Fallen Kingdom may one day have an impact on future paleontologists. This also presented a great opportunity to get some scientific queries from a non-scientist. My partner for this episode is Tommy Dembeck, an old friend from my days as an undergraduate at McDaniel College with whom I discuss sci-fi endlessly. He is also endlessly curious. Of all the laypeople I know who have never worked in a university or museum setting, Tommy has the best questions about biology and prehistory. I would love to have him back for a future episode…there are always shark movies to talk about! I’ve uploaded the full audio of our discussion to this blog post if you want to hear more of our Jurassic World Fallen Kingdom thoughts in two parts! http://www.pasttime.org/wp-content/uploads/2018/08/JurassicWorld_Tommy_Part1.mp3 http://www.pasttime.org/wp-content/uploads/2018/08/JurassicWorld_Tommy_Part2.mp3 FURTHER READING Check out our previous episodes on… “Genes and Jurassic Park“, in which Matt discusses his thoughts about the movie and genetic engineering. …and “New History of Ancient DNA,” which features an interview from Dr. Elizabeth Jones about the history of molecular paleontology and the impacts of science fiction! Visit the Jurassic World website for updates on the movies, games, and other media (for better or for worse). Adam really likes that Jurassic World Alive mobile game…it’s not great, but it actually has Concavenator!
32 minutes | Jul 27, 2018
Episode 27 – Machairoceratops: An Extinct Horned Dinosaur Under Threat!
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 found was cut from Grand Staircase-Escalante National Monument, threatening our chances of making new discoveries about dinosaur evolution there. Join us on this episode to meet one of our favorite ceratopsian researchers, marvel at the grandeur of Machairoceratops, and mourn the loss of protections for some incredible vertebrate fossil sites. Hunting Horned Dinosaurs with Eric Lund! We want to thank our guest on this episode, Eric Lund, for clearing up some of our ceratopsian confusion! Although we interviewed him while he was a student at Ohio University, he’ll be finishing up his PhD while he works in his new position in the Paleontology Research Lab at the North Carolina Museum of Natural Sciences. You can follow him on Twitter at @Bwana_Lund. And be sure to check out the scientific article he led about Machairoceratops cronusi in the journal PLOS ONE! Dig Deeper… On this episode, Eric Lund introduces us to the incredibly fossil-rich and scientifically significant Kaiparowits Plateau of Grand Staircase-Escalante National Monument. You can learn more about it in this New York Times article from 2015 and download an awesome poster about the dinosaurs of the monument designed by Blue Aster Studio. Check out the original paper for free in the science journal Plos One! The spectacular paleo-art featured in the promo image was painted by paleoartist Mark Witton. Check out his blog and art gallery. We also touch on the idea of ownership of vertebrate fossils, which tell the story of the evolution of our planet, and the laws surrounding these shared resources in the United States. This How Stuff Works article explains the debate about fossil ownership, and this webpage from the Society of Vertebrate Paleontology explains the Paleontological Resources Preservation Act. It may be confusing for a paleontology podcast to wade into politics, but when you’re talking about a fossil found in a national monument, it is impossible not to. Everyone you hear on this episode is a member of the Society of Vertebrate Paleontology (SVP), and one of the goals of SVP is “To support and encourage the discover, conservation and protection of vertebrate fossils and fossil sites” (SVP Code of Ethics). In line with this Code of Ethics, SVP is taking legal action to prevent the cuts to two national monuments that would endanger significant vertebrate fossil sites. SVP explains its position with useful maps and graphics here, and this interview with Dr. P. David Polly, the outgoing President of SVP, provides more information.
16 minutes | Jul 13, 2018
Episode 26 – Colobops: the tiny reptile with a big bite!
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 long. However, intensive research and three-dimensional modeling revealed that it possessed cavities for its jaw muscles larger than any other reptile of that size—living OR extinct! Colobops likely nipped at the heels of some of the earliest dinosaurs and crocodile cousins in North America. Dig Deeper The original paper can be read for free in the journal Nature Communications! Adam’s co-author Bhart-Anjan Bhullar, professor of Geology at Yale University, helped produce a great video on the discovery with Yale University’s press office. The brilliant reconstruction of Colobops was hand painted by paleoartist and Geology Ph.D. student at Yale Michael Z. Hanson. Mike will be appearing in an upcoming episode of Past Time on the early days of bird evolution. If you want to see the original Colobops specimen, travel to the Yale Peabody Museum in New Haven, Connecticut!
4 minutes | Jun 28, 2018
Episode 25 – Ceratosaurs: Story of a Predatory Dinosaur Dynasty!
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 like Masiakasaurus, Limusaurus, and Elaphrosaurus—ceratosaurs included top-of-the-food-chain carnivores and slender, fleet-footed herbivores. For this episode, I delve into a cool new paper summing up the current knowledge on these awesome beasts! References Read the original paper by paleontologist Rafael Delcourt for free in the journal Scientific Reports! For some awesome skeletal mounts of ceratosaurs, you can visit museums around the world. See Ceratosaurus at the Natural History Museum of Utah in Salt Lake City and Carnotaurus at the Natural History Museum of Los Angeles and the Museo Argentino de Ciencias Naturales B. Rivadiva in Buenos Aires! The great traveling exhibit Ultimate Dinosaurs-Giants of Gondwana has a number of ceratosaur skeletons too! Please add a comment if you have another ceratosaur museum to suggest!
9 minutes | May 3, 2018
Episode 24 – Dinosaurs and crocodiles in the Land Before Egypt!
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 much harder to come by. Indeed, most of the fossils record of Cretaceous dinosaurs and their contemporaries were collected during a small number of expeditions in the early twentieth century by German paleontologist Ernst Stromer. Ernst Stromer during an early twentieth century expedition to the Bahariya Oasis. The identity of his Egyptian associate is unknown. Please message us if you have any ideas! Stromer’s work focused on the “middle” part of the Cretaceous Period: between ~100–90 million years ago. Most of those discoveries—including the original type specimens of dinosaurs like Spinosaurus, Carcharodontosaurus, and Aegyptosaurus—were destroyed in bombings during World War II. For over sixty years, no substantive further discoveries of Mesozoic Egyptian fossils occurred. In the early 2000s, American paleontologists Matthew Lamanna and an international team returned to the Bahariya Oasis and discovered a variety of new dinosaurs, including a supergiant titanosaur Paralititan stromeri now housed in the Cairo Geological Museum. The Mansoura University Vertebrate Paleontology project highlighted in this episode extends those efforts into new fossil deposits into the Quseir Formation of the Western Desert of Egypt, preserving fossils from much later in time than those of the Bahariya Oasis. The Quseir fossils are some of the best records of terrestrial backboned animals from the end of the Cretaceous Period from the whole of Africa. This was also at a time when Africa was an island continent, isolated without land connections with other continents. That makes Africa prime real estate for finding unique fossil ecosystems. Dr. Heham Sallam leads the Mansoura University Vertebrate Paleontology (MUVP) team to the new frontier of vertebrate paleontology in Egypt. Educated at Oxford University, Hesham is one of the first native Egyptians to lead a scientific paleo project. He is training a large number of students in the science of vertebrate paleontology and Mansoura University. His current graduate students include Sana El-Sayed, Eman Abd El Aziz, and Sara Saber. Ms. El-Sayed holds the distinction of being the first woman paleontologist from the Middle East to lead a scientific publication, which described a giant catfish from the early Cenozoic. Sara Saber published the most recent MUVP paper describing the Cretaceous crocodile relative Wahasuchus, which is featured in this paper. The leaders of the recent publications out of the Mansoura University paleontology program. Top: Hesham Sallam, displaying the type specimen of Mansourasaurus. Lower Left: Sara Saber, who described Wahasuchus. Lower right: Sana El-Sayed, who described the giant Eocene catfish Qarmoutus. The award-winning MUVP team is not only developing field expeditions in the Western Desert and the Fayum Depression, but also the laboratory side of the process. The fossils of Mansourasaurus and Wahasuchus are housed in the collections of Mansoura University. There is a new fossil preparation facility, and the scientists have access to CT scanning technology as well. I am very excited to see more dinosaurs and all sorts of fossil beasts pulled from the Egyptian sands by this team. Left: Life reconstruction of Mansourasaurus by Andrew McAfee of the Carnegie Museum of Natural History. Right: A sampling of the fossil bones recovered from Mansourasaurus from the original paper by Sallam et al. A line drawing of the skull of Wahasuchus from the original paper by Saber et al. Blue bones include the original type skull. Green bones are based on additional specimens. Further Reading – On the Mansoura University program: The Mansoura University Vertebrate Paleontology website outlines the current work by the team. If you are a student interested in Egyptian paleontology, send them an e-mail! http://islandafrica.org/muvp.htm Sallam was interviewed about the progress of Egyptian paleontology in the past century by Daily New Egypt. https://dailynewsegypt.com/2018/01/10/hesham-sallam-tells-egypts-tale-fossil-remains/ Sana El-Sayid, who led the project describing a new catfish fossil from the Fayum Depression, was also interviewed about her experiences as a paleontologist by Discovery Magazine. http://blogs.discovermagazine.com/deadthings/2017/03/03/egypts-catfish-hunter-sanaa-el-sayed/#.WukmGNPwbaY On Mansourasaurus: The original paper describing Mansourasaurus was led by Dr. Sallam and published in the journal Nature Ecology & Evolution. A pdf copy can be accessed at the link: https://www.researchgate.net/profile/Hesham_Sallam/publication/322766471_New_Egyptian_sauropod_reveals_Late_Cretaceous_dinosaur_dispersal_between_Europe_and_Africa/links/5a709e7daca272e425ed297d/New-Egyptian-sauropod-reveals-Late-Cretaceous-dinosaur-dispersal-between-Europe-and-Africa.pdf Paleontologist and blogger Brian Switek outlined the nitty-gritty of the Mansourasaurus discovery in his Laelaps blog. https://blogs.scientificamerican.com/laelaps/paleo-profile-the-mansaoura-lizard/ Hesham also published a personal account of the Mansourasaurus discovery in the Nature https://natureecoevocommunity.nature.com/users/78412-hesham-sallam/posts/29712-mansourasaurus-a-story-from-the-land-of-pharaoh-and-dinosaurs The only good videos of the Mansourasaurus discoveries were a loooong series of interviews with Hesham and other Mansoura University paleontologists from Egyptian TV. Note that these are in Arabic. https://www.youtube.com/watch?v=yZ9JqY2ZvfU&list=PL_EUIOTK5yDItsLCfSbyp0OhnQI_57wEN Licensed material used in the episode and associated images: Egyptian folk music by Mohamed El-Sayed. Mansourasaurus call modified from Elephant sound effects by ULTRABROS123 (Youtube). Alligator bellow from astronomica via freesounds.org.
14 minutes | Mar 22, 2018
Episode 23: Meet the Echinoderms! Adventures with Ancient Sea Stars!
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! Yale University Ph.D. student Elizabeth Clark, holding examples of modern-day echinoderms. The animal on the left is a sea star (Asteroidea), while the animal on the right is a brittle star (Ophiuroidea). This episode would not have happened with Elizabeth Clark, graduate student in the Geology Department at Yale University and my gateway to echinoderms. As a part of the lab of Derek Briggs, Liz has studied a wide range of topics on echinoderm paleontology and biology. You can check out the original scientific paper on her Ordovician asteroid in Biology Letters and the Yale News story about the discovery. The original specimen of Protasterina flexuosa featured in the study is pictured below. It actually lived alongside the Flexicalymene trilobites featured in our previous invertebrate episode. You can see their fossils (and hundreds of thousands of others) at the Cincinnati Museum Center in Cincinnati, Ohio. The ventral side of Protasterina flexuosa. From left to right: 1) a three-dimensional model of CT scan data, 2) the model with the water vascular system inside, 3) the water vascular system in 3D. Scurrying with Sea Stars, Crawling with Crinoids, and Battling with Brittle Stars! I had a lot of fun watching echinoderms locomote while making this podcast. I really cannot believe the diversity of movement styles they adopted throughout their history. A lot of this system is built on the water vascular system and associated tube feet, but many species explore different methods for motion. Check ‘em out below! Sea star (Asteroidea) stranded on a beach, but working its arms and tube feet like crazy to reach the shoreline. Brittle stars (Ophiuroidea) walking around the seafloor AND battling over a shrimp dinner! A sea urchin (Echinoidea) walks across the glass surface of an aquarium, exposing its tube feet. This video features many sea cucumbers, scurrying around and vacuuming up the sea floor in search of dinner. It also features an unusual symbiosis, in which a fish lives inside of the sea cucumber’s anus. A bizarre type of sea cucumbers, sea pigs have very large tube feet that let them walk like insects! Clearly not using tube feet here! Sea cucumbers can also propel themselves by flexing and extending their whole bodies to swim! Crinoids, the plant-like echinoderms that anchor themselves to the sea floor, don’t seem like good candidates for moving around… …but they can move like any other echinoderm when they want, using their arms to walk… …and others flex their feather-like arms to swim! Echinoderm armies! Sea stars, brittle stars, sand dollars, and urchins battle it out and shape the reefs and landscapes. Further Reading: Liz Clark’s paper on the Protasterina specimen: Clark, E. G., Bhullar, B.-A. S., Darroch, S. A. & Briggs, D. E. Water vascular system architecture in an Ordovician ophiuroid. Biology Letters 13, 20170635 (2017). Fossil Focus is a recurring article produced by the Palaeontological Association. Some of its past articles have featured families of echinoderms: https://www.palaeontologyonline.com/articles/category/fossil-focus/ Echinoblog covers all aspects of modern-day echinoderm research and zoology. Lots of cool images of modern-day species. http://echinoblog.blogspot.com/ Scripps Institute of Oceanography also covers the details of the fossil record of echinoderms, back to their origin over 540 million years ago. Just like Liz said, there are a LOT more fossil echinoderm species than living ones. Consider this site an introduction to the topic. https://scripps.ucsd.edu/centers/echinotol/about-echinoderms/fossil-record-of-echinoderms/ Licensed material used in the episode and associated images: Epic ophiuroid arm theme: “Epic” from bensound.com. CC 3.0 license. “Aquarium” by Camille Saint Saens, performed by Aitua from http://freemusicarchive.org/music/Aitua/Carnaval_des_Animaux/Aitua_-_07_Camille_Saint_Saens_-_Carnaval_des_animaux_-_VII_Aquarium . CC 4.0 license.
14 minutes | Dec 8, 2017
Episode 22: Matheronodon, a new dinosaur with a different kind of bite!
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 Reports! If you’d like to learn more about Rhabdodontidae, the small but successful family of dinosaurs to which Matheronodon belongs, check out the papers in the reference list below. The head of Matheronodon, complete with gigantic teeth in its jaws. This illustration by Lukas Panzarin reconstructs the whole head similar to other rhabdodonts, like Rhabdodon and Zalmoxes. Museum of Matheronodon The original specimen (pictured below) is housed at the Musée du Moulin Seigneurial in Velaux, France. I looked up the museum online, and it looks really cool. Built in an old olive mill, the exhibits include Cretaceous in Provence displays. The displays include specimens of Matheronodon contemporaries, including the sauropod Atsinganosaurus velauciensis, the crocodile Allodaposuchus, and ancient turtles. If I get a chance to visit, I’m hoping the Matheronodon teeth and jaws will be there too! Figure 1 of the paper by Godefroit et al. (2017), illustrating the right maxilla of Matheronodon with its giant teeth. Ali Nabavizadeh and his biting dinosaur commentary Our guest this episode was Dr. Ali Nabavizadeh, who was not actually involved in the study. But, he is one of the most knowledgable scientists working on dinosaur jaws! His work focuses on the evolution of eating in herbivorous animals. His early work focused entirely on dinosaurs, but he has branched out into other plant-eating reptiles and mammals. Ali’s work was featured on a classic episode of Past Time on just how different dinosaur bites could be. You can visit his research website, and, if you are a student at the Cooper Medical School at Rowan University, he might be your anatomy professor! Follow him on Twitter for something to chew on! FURTHER READING The new paper describing Matheronodon. Godefroit, P., Garcia, G., Gomez, B., Stein, K., Cincotta, A., Lefèvre, U. & Valentin, X. 2017. Extreme tooth enlargement in a new Late Cretaceous rhabdodontid dinosaur from Southern France. Scientific Reports, 7, 13098. An older paper led by Dr. Godefroit on Zalmoxes, a much more completely known rhabdodont from Cretaceous Romania. Godefroit, P., Codrea, V. & Weishampel, D. B. 2009. Osteology of Zalmoxes shqiperorum (Dinosauria, Ornithopoda), based on new specimens from the Upper Cretaceous of Năălaţţ-Vad (Romania). Geodiversitas, 31, 525–553. A paper led by Hungarian researcher Attila Osi about the biggest and smallest rhabdodonts from Europe. Osi, A., Prondvai, E., Butler, R. & Weishampel, D. B. 2012. Phylogeny, histology and inferred body size evolution in a new rhabdodontid dinosaur from the Late Cretaceous of Hungary. PLoS One, 7, e44318. Dr. Nabavizadeh’s paper on the diversity of chewing in the ornithschian dinosaurs. Nabavizadeh, A. 2016. Evolutionary trends in the jaw adductor mechanics of ornithischian dinosaurs. The Anatomical Record, 299, 271–294. Be sure to check out Past Time on Twitter and Facebook. Give us a review on iTunes if you get the chance too!
27 minutes | Oct 13, 2017
Episode 21: New History of Ancient DNA
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 College London, about her work digging through the murky early history of ancient DNA and the dynamic scientists who are trying to figure out how fossils sometimes preserve more than bone. Dr. Elizabeth Jones recently defended her dissertation work at University College London on the historical roots of ancient DNA research. She also has experience as a field paleontologist. Here, she’s on an excavation looking for more traditional fossilized bone rather than molecular fossils. One of Dr. Jones’s amazing contributions to the history of science is her work interviewing the people who have been thinking about and trying to recover ancient DNA. As a historian of science, she can put look at larger trends in how ideas get passed around between scientists, and how media and public interest affects the scientific process. One key distinction to remember is there is a difference between researchers who are interested in recovering ancient DNA to study what it might tell us about ancient populations or the relationships of ancient animals to modern animals. There’s a whole separate field of researchers who are trying to figure out how to resurrect extinct animals using ancient DNA and cloning technology. These fields feed interest in each other, but they involve different techniques, different philosophical questions, and different research questions. Dr. Jones calls Ancient DNA research a “celebrity science” because each new revelation gets tons of media attention. Listen to our discussion to learn more about where the field started and what might be on the horizon! Dig Deeper! An article summarizing all the amazing insights Neanderthal DNA has revealed: https://www.theverge.com/2017/10/9/16448412/neanderthal-stone-age-human-genes-dna-schizophrenia-cholesterol-hair-skin-loneliness An article covering Dr. Mary Schweitzer’s work on dinosaur proteins: http://www.sciencemag.org/news/2017/09/i-don-t-care-what-they-say-about-me-paleontologist-stares-down-critics-her-hunt
34 minutes | Sep 25, 2017
Episode 20: Digging the Dawn of Dinosaurs – Paleontology at Ghost Ranch
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 of the strangest reptiles that ever lived. I’ve been proud to be a part of the Ghost Ranch field crew for nearly a decade now! Paleontologist Adam Pritchard excavating around a mini plaster jacket, likely containing some kind of tiny reptile fossil. The 2017 Ghost Ranch field crew, standing proud by H4. First off, here are some links to exhibits and museum experiences relating to the Ghost Ranch project, including the recent Hayden Quarry discoveries: The Ruth Hall Museum of Paleontology at Ghost Ranch https://www.ghostranch.org/explore/museums/museum-of-paleontology/ Check out the Ghost Ranch exhibit in the heart of it all, filled with the awesome fossils from the Triassic Period. Includes links for school groups and to join tours of the local fossil sites led by Ghost Ranch staffers! Paleontology at Ghost Ranch Jan-Term courses https://www.ghostranch.org/retreats/category/retreats/archaeology-geology-paleontology/ In addition to summer classes, there is a winter paleontology experience at Ghost Ranch that runs through January. Members of the classes have discovered some amazing, valuable fossils from the Hayden Quarry site! Shelf Life episode about the Ghost Ranch area and dinosaur evolution. https://www.youtube.com/watch?v=567bv6xmuss A video from the American Museum of Natural History on its role in uncovering the amazing discoveries at the Coelophysis I thought it’d also be good to add some links to the MANY books scientific papers that have come out of Ghost Ranch paleontology since the beginning of the twentieth century: Colbert EH. 1995. Little Dinosaurs of Ghost Ranch. Columbia University Press, New York. 232 pp. Popular book on Ghost Ranch dinosaur discoveries by the great twentieth century paleontology Edwin Colbert (who deserves GREAT thanks for his contribution to the discovery of the original Coelophysis. Colbert EH. 1989. The Triassic dinosaur Coelophysis. Museum of Northern Arizona Bulletin 57:1–160. Classic paper on anatomy of the classic Ghost Ranch dinosaur and the history of its discovery. Currently not available online, as far as I can tell. Long RA and Murry PA. 1995. Late Traissic (Carnian and Norian) tetrapods from the southwestern United States. Bulletin of the New Mexico Museum of Natural History 4. http://econtent.unm.edu/cdm/compoundobject/collection/bulletins/id/659/rec/26 Massive tome on the whole diversity of four-footed animals in the Triassic southwest, as it was understood in the 1990s. Lots of good information! Irmis RB, Nesbitt SJ, Padian K, Smith ND, Turner AH, Downs A. 2007. A Late Triassic dinosauromorph assemblage from New Mexico and the rise of dinosaurs. Science 317:358–361. https://scholar.google.com/scholar?cluster=3400428144708398818&hl=en&as_sdt=0,21 The first major scientific publication from the Hayden Quarry project, detailing the dinosaur and dinosaur-cousin parts of the fauna. Nesbitt SJ, Smith ND, Irmis RB, Turner AH, Downs A, Norell MA. 2009. A complete skeleton of a Late Triassic saurischian from the early evolution of dinosaurs. Science 326:1530–1533. https://scholar.google.com/scholar?cluster=6320869846132121740&hl=en&as_sdt=0,21 Description of Tawa hallae, the early theropod dinosaur unique to the Hayden Quarry fauna. Whiteside JH, et al. 2015. Extreme ecosystem instability suppressed tropical dinosaur dominance for 30 million years. Proceedings of the National Academy of Sciences 112:7909–7913. https://scholar.google.com/scholar?cluster=8226127600494641823&hl=en&as_sdt=0,21 Awesome paper on the strange, unstable ecosystem and forest fires recorded in the Hayden Quarry fossil site. Lessner EJ, Stocker MR, Smith ND, Turner AH, Irmis RB, Nesbitt SJ. 2016. A new rauisuchid (Archosauria, Pseudosuchia) from the Upper Triassic (Norian) of New Mexico increases the diversity and temporal range of the clade. PeerJ 4:e2336. https://peerj.com/articles/2336/?utm_source=TrendMD&utm_campaign=PeerJ_TrendMD_0&utm_medium=TrendMD Description of the giant predatory rauisuchian from the Hayden Quarry site. Pritchard AC, Turner AH, Nesbitt SJ, Irmis RB, Smith ND. 2015. Late Triassic tanystropheids (Reptilia, Archosauromorpha) from northern New Mexico (Petrified Forest Member, Chinle Formation) and the biogeography, functional morphology, and evolution of Tanystropheidae. Journal of Vertebrate Paleontology 35: e911186. https://scholar.google.com/scholar?cluster=4784541546423146723&hl=en&as_sdt=0,21 My own paper on the weird, long-necked tanystropheids from the Hayden Quarry. Hit me up if you can’t find a copy. Pritchard AC, Turner AH, Irmis RB, Nesbitt SJ, Smith ND. 2016. Extreme modification of the tetrapod forelimb in a Triassic diapsid reptile. Current Biology 26:2779–2786. https://scholar.google.com/scholar?cluster=12454567957351173151&hl=en&as_sdt=0,21 Last and perhaps least, my recent paper on the crazy arms of Drepanosaurus, the bizarre, giant-clawed reptile. The end of a long day of fieldwork. Everyone gathers at the campground and waits hungrily for dinner. Be sure to like us on Facebook, follow us on Twitter, and give us a review on iTunes if you like the podcast!
12 minutes | Jul 10, 2017
Episode 19: Masrasector—Egypt’s Ancient Slicer!
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 monkey-like relatives! Here’s a link to the original paper in the open access journal PLOS ONE <http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0173527> if you want to take a look at the original fossils. You can even see them in 3D at www.morphosource.org Masrasector means “The Egyptian slicer” because the meat-eater was found in the deserts of Egypt, near the Fayum Oasis southwest of Cairo. The species name, nananubis, means “tiny Anubis,” because the small, fox-sized carnivore resembles the jackal-headed Ancient Egyptian god of embalming and guide through the afterlife. “Tiny Anubis” likely scrambled on the ground, chasing large rodents and small hyraxes through the Fayum wetland. It probably didn’t spend a lot of time weighing the hearts of the dead, but such behaviors don’t fossilize very well. Masrasector nananubis was part of an extinct group of carnivorous mammals called hyaenodonts. If you think of a meat-eating mammal today, like a wolf, tiger, or hyena, you’re thinking of a species from the mammalian order Carnivora. Carnivorans are united by having one pair of specialized meat-slicing teeth on each side of their face. Next time you see a dog or cat yawn, look in the back of their mouth for the scissor-like blades. Hyaenodonts had three pairs of these meat-slicers on each side of their mouths instead of just one, making it easy to recognize them in the fossil record. Hyaenodonts were the only meat-eating mammals in Africa for over forty million years between the extinction of the dinosaurs and the arrival of the first African carnivorans. Carnivorous mammals are rare in modern ecosystems, and this was also true in the past. Fossilization itself is a rare event, which means the chances of a rare carnivore becoming a rare fossil are very low. This means African hyaenodonts are a rare find, and most are only known from a few isolated teeth and jaws. But, Masrasector is known from several nearly complete skulls, dozens of jaws, and pieces of arm bone. A photograph and three-dimensional model of the skull of Masrasector nananubis. With all this material it’s possible to really dig into what Masrasector ate, and how it moved through its environment. African carnivores like lions and hyenas are fascinating, endangered creatures. Hyaenodonts were a separate experiment in how to be a carnivorous African mammal, and they did it successfully for millions of years.Masrasector offers a detailed view of how African hyaenodonts pursued their prey and what their diet was like. The specimens were discovered in a quarry called Locality-41, one of the most fossil-rich places from the beginning of the Age of Mammals in Africa. The first specimens of Masrasector were found at L-41 nearly 30 years ago. For decades, the specimens accumulated as Egyptian and American paleontologists delicately removed the fossils from the salty, clay-like rock they were embedded in. Hundreds of people moved the sediment, prepared the specimens, and protect these delicate fossils, which need to be kept in a humidity-controlled room because the salt and clay they were fossilized in can expand and break the bones. Salt was an important ingredient in the mummification process, which is another reason naming Masrasector nananubis after the god of embalming made sense. Matt and Erik investigate new fossils during fieldwork in the Fayum Depression of Egypt. “The Fayum deposits give us our most detailed insights into the early evolution of Africa’s native mammals, when that continent was still largely isolated from other landmasses,” says Eric Seiffert, co-author on the study and Professor in Integrative Anatomical Sciences at the University of Southern California. “The small carnivorous mammals from the Fayum sites were previously only known from a few jaw fragments and isolated teeth, so the discovery of complete crania and arm bones of Masrasector provides lots of new information that allows us to better understand what these animals looked like, what their adaptations were, and how they might have fit into these ancient ecosystems. Because the specimens are so delicate, many were micro-CT scanned at Duke University to create digital models of the specimens. Now the digital models can be shared widely and studied by researchers around the world, without needing to handle the delicate specimens. With all the anatomical detail provided by the specimens, it was possible to run an analysis using new analytical methods to understand where Masrasector fits in the hyaenodont family tree. The results reveal Masrasector is part of a group of hyaenodonts that were part of African ecosystems for millions of years: Teratodontinae. The oldest species in Teratodontinae is nearly 50 million years old and the youngest shared the landscape with the early relatives of dogs, cats, and mongooses that crossed into Africa when the Arabian Peninsula connected Africa to Eurasia. Teratodontines, were an integral part of African landscape, shaping the same ecosystems where we find our ape and monkey relatives. Then hyaenodonts passed the ecological baton to modern carnivores. All of this Masrasector material helps to sort out their anatomy and relationships, so researchers can piece together what ecological role modern African carnivores inherited from these ancient beasts. To reconstruct the ecology of Masrasector, the researchers took measurements of the arm bones of Masrasector, other hyaenodonts, and modern carnivorans. Because the locomotion of modern carnivorans is known from actually watching them move, the researchers used a classification analysis to predict Masrasector was a ground-based carnivore, like a modern fox or hyena. An illustration of Hyaenodon, a large North American relative of Masrasector by paleoartist Nobu Tamura. This illustration captures the large rectangular skull of hyaenodonts. The discovery of Masrasector nananubis allowed Matt and Dr. Seiffert to delve into the ancient lives of a mysterious group of African carnivorous mammals. With the scans of the specimens and the measurements accessible online, “tiny Anubis” can continue to guide researchers through the evolution and extinction of Africa’s first meat-eating mammals. This study was funded by grants from the National Science Foundation Division of Biological Infrastructure, Division of Behavioral and Cognitive Sciences, and Division of Environmental Biology, The Leakey Foundation, The Explorers Club, Gordon and Ann Getty, and the Society for Integrative and Comparative Biology.
26 minutes | Jun 24, 2017
Episode 18: The Bird Brains and the Dinosaur Expert
17 minutes | Feb 3, 2017
Episode 17: Kingdom of the Monkey Lizard!
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! Painting of Drepanosaurus by paleoartist Victor Leshyk, commissioned for the publication of the New Mexico Drepanosaurus fossils In this episode, Matt interviews Adam about his research into the early days of the Age of Reptiles and the strange non-dinosaurs living 212 million years ago in New Mexico. Come face-to-face with Drepanosaurus, one of the strangest reptiles that ever lived on Earth, and one that has presented an anatomical mystery for over thirty years! Nicknamed “the monkey lizard,”iIt had arms like no other animal, a claw on the end of its tail, and likely lived like a modern anteater! For more information on this project, you can check out Adam’s original article and the news article produced by Yale University!
6 minutes | Aug 30, 2016
A Food Chain in a Fossil: A snake skeleton with its prey still inside!
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 Triceratops bones that match closely with tyrannosaur teeth. However, it’s very rare to run across fossils that preserve an animal’s meal still in its rib cage. It’s far rarer for that meal to still have IT’S last meal in IT’S STOMACH! But that’s just the kind of fossil I talk about on Past Time today: a snake skeleton with a lizard in its stomach region, and that lizard with a partial insect still inside! I couldn’t believe the pictures when I saw them, but paleontologists Krister Smith and Augustín Scanferla have a slam-dunk case that the boa-like snake Palaeopython ate a basilisk lizard Geiseltaliellus. And, before being eaten, that lizard ate a tiny insect. That’s a whole lot of ecosystem preserved in a single fossil! The original fossil with all three links in the food chain illustrated. Hailing from the Messel Pit fossil site in Germany, this nearly complete snake skeleton suggests that Palaeopython ate its prey in very much the same way as modern snakes. Spectacular fossils like this can reveal amazing truths about ancient ecosystems and just how different they were from the world today! Dig Deeper (Links and References): For more on this discovery, check out the original research paper by Krister Smith of the Department of Palaeoanthropology and Messel Research at the Senckenberg Research Institute in Germany and Augustín Scanferla of the Instituto de Bio y Geociencias del NOA (IBIGEO) in Salta, Argentina. Read it at http://link.springer.com/article/10.1007/s12549-016-0244-1. Past Time covered the Messel fossil site in a classic episode with Matt and Adam! Check it out at http://www.pasttime.org/2013/08/episode-6-field-guide-tiny-horses-galloping-crocs-and-fossilized-jungles/. The Guardian newspaper reported on some of the spectacular fossils of Messel, and published some amazing photos of the crocs, birds, mammals, and insects at https://www.theguardian.com/science/gallery/2009/may/19/fossil-ida-missing-link. And check out a much older case of a three-level trophic interaction involving a shark, amphibians, and an ancient fish at this link: http://rspb.royalsocietypublishing.org/content/275/1631/181.short Be sure to like Past Time on Facebook at https://www.facebook.com/pasttimepaleo/ and follow us on Twitter at https://twitter.com/PastTimePaleo!
7 minutes | Aug 15, 2016
Grandma Sharkie: The Greenland Shark is the World’s Oldest Vertebrate Animal!
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 400 years, if not more! Just goes to show that you don’t always need fossils to learn about natural history. Check it out in the latest episode of Past Time! Greenland Sharks are slow-moving predators. They seem to capture seals and other prey items while they are resting. FURTHER READING: Read about the original study at: http://www.sciencemag.org/news/2016/08/greenland-shark-may-live-400-years-smashing-longevity-record More studies on growth in marine animals use bomb radiocarbon, too, including this study of the Great White. The study linked here was the first to use this method on the age of living sharks. For some awesome pictures of the Greenland Shark in nature, check out ARKIVE.org.