The Fossil Files

Sometimes the answer to palaeontological mysteries can actually be right in front of our faces, if only we know how, or where, to look. This week we take a look a two cases by the Fossils Files' own Susie, Rob and Jane. Firstly, we reveal how the eyes and skeletons of early vertebrates were right in front of us, hidden in Silurian Scottish fish fossils, but only observable when we applied high powered X-ray analysis to them. Secondly, we look at the mystery of the missing European ceratopsian dinosaurs. Turns out these horned dinosaurs were there all along after a new discovery from the Cretaceous of Hungary shook up the family tree.  So this week the Fossil Files gets a bit self-involved as we discuss about our own research. The first paper was by Jane Reeves (behind the scenes contributor to The Fossil Files), with Rob Sansom and colleauges in Manchester and California, published in Proceedings of the Royal Society B in January 2026 "Early vertebrate biomineralization and eye structure determined by synchrotron X-ray analyses of Silurian jawless fish" https://doi.org/10.1098/rspb.2025.2248 The second paper was by Susie Maidment, Richad Butler, Steve Brusatte, Luke Meade, and colleauges in Hungary, Germany and Romania published in Nature in January 2026 "A hidden diversity of ceratopsian dinosaurs in Late Cretaceous Europe" https://doi.org/10.1038/s41586-025-09897-w Another paper we mention when talking about fossil fish came out the same week of Jane's paper in Nature by Xiangton Lei and colleagues published in Nature in January 2026 "Four camera-type eyes in the earliest vertebrates from the Cambrian Period" https://doi.org/10.1038/s41586-025-09966-0 Wide screen art by Matt Dempsey. 

Life nearly died 252 million years ago in a mass extinction at the end of the Permian. It was long thought that it took 10s of millions of years into the Triassic for life to recover and get back to a 'new normal'. That was until a new and very muddy fossil site from the high Arctic revealed a staggering diversity of predators and tetrapods in the earliest Triassic seas. This week we take a look at the new findings and its implications for life's ability to recover from major extinctions.  This week's paper is "Earliest oceanic tetrapod ecosystem reveals rapid complexification of Triassic marine communities" by Aubrey Roberts, published in Science in November 2025 DOI: 10.1126/science.adx739 An accessible summary can be found here. You can see lots of nice pictures and get some extra context from some slides by Jørn Hurum here Wide screen art by Robert Back. 

Lead is a well known pollutant affecting human health over the course of our urbanisation and industrialisation. But what about before this? Analysis of a range of fossil hominid teeth from the Pleistocene reveals that lead poisoning might have been a ubiquitious part of our deep evolutionary history. Furthermore, lab experiments looking at the effect of lead exposure on human and neanderthal brain development reveals the interplay between this pollutant and 'the language gene' (FOXP2). Together, this suggests that the development of language, socialisation and ultimate evolutionary success of humans might be related to our ability to overcome lead poisoning.  This week's paper is "Impact of intermittent lead exposure on hominid brain evolution" by Renaud Joannes-Boyau and colleagues published in Science Advances, October 2025. https://doi.org/10.1126/sciadv.adr1524 Wide screen art by Mark Witton

Having large body sizes conferred all sorts of advantages on dinosaurs, but it potentially made breeding a bit complicated. This week we take a look at some weird pathologies in fossil hadrosaurs (duck billed dinosaurs and friends) and what they might tell us about their amourous habits - do broken backs provide evidence of rough housing in the bedroom?  This week's paper is "Deciphering causes and behaviors: A recurrent pattern of tail injuries in hadrosaurid dinosaurs" by Filippo Bertozzo and colleagues, published in IScience November 2025 https://doi.org/10.1016/j.isci.2025.113739 The widescreen artwork is by Troco.  

Part 2: Around 66 million years ago an enormous asteroid barrelled into the earth and wiped out  ichthyosaurs, pterosaurs, and dinosaurs*. Debate has raged back and forth as to whether the dinosaurs were already in decline before this mass extinction or were still going strong. This week, Susie and Rob are joined by Prof. Steve Brusatte to take a look at what vertebrates were doing just before the asteroid hit. In part 2 we discuss what would have happened if the asteroid had missed, Steve's new upcoming book, Jurassic World, and Nannotyrannus.  *except birds of course. Widescreen artwork by Natalia Jagielska

Around 66 million years ago an enormous asteroid barreled into the earth and wiped out  icthyosaurs, pterosaurs, and dinosaurs*. Debate has raged back and forth as to whether the dinosaurs were already in decline before this mass extinction or were still going strong. This week, Susie and Rob are joined by Prof. Steve Brusatte to take a look at what vertebrates were doing just before the asteroid hit. We discuss his new paper on fossil vertebrates from New Mexico, its implications for scenarios of dinosaur evolution and extinction, and what is life is like for a working palaeontologist, digging up Cretaceous fossils.  This week's paper is "Late-surviving New Mexican dinosaurs illuminate high end-Cretaceous diversity and provinciality" by Andrew Flynn, Steve Brusatte and colleagues, published in Science in October 2025. https://doi.org/10.1126/science.adw3282 *except birds of course. Widescreen artwork by Natalia Jagielska

Artificial Intelligence seems to be changing everything, everywhere, all at once. But how will the science of studying the very old be transformed by the technology of the new? In this episode Susie and Rob take a look at the risks and opportunities for palaeontology with the application of AI: palAIontology. Can we use AI to find, identify, and classify fossils?  The paper's discussed this week are: "Artificial intelligence in paleontology" by Congyu Yu and colleagues published in Earth Science Reviews May 2024 https://doi.org/10.1016/j.earscirev.2024.104765 and "Early humans and the balance of power: Homo habilis as prey" by Marina Vegara-Riquelme and colleagues published in Annals of the New York Academy of Sciences in September 2025  https://doi.org/10.1111/nyas.15321

In the last of our series from the massive Society of Vertebrate Paleontology meeting, Susie and Rob finally manage to catch up for a gossip. In this episode with get a disgusting taste of rotting crocodile experiments with Stephanie Drumheller of the University of Tennessee, an insight into the Dinosaur battle bus education project that has been travelling the Mongolian steppe with Bolor Minjin of the American Museum of Natural History and the Institute for the Study of Mongolian Dinosaurs, and finally how engineering approaches can help us figure out what fossil organisms were up to long after their death with Emily Rayfield, University of Bristol. 

New fossil discoveries keep coming thick and fast, but we managed to sit down with the researchers as they present them. In this episode Susie and Rob catch up (in person!) on their second day in Birmingham and talk to the researchers tackling important transitions in vertebrate evolution: the transitions of moving onto land, into the sea, into the air. This includes Emily Hillan of University of Chicago and her discovery of a new specimen of the walking fish (?) Tiktaalik, Dave Hone of Queen Mary University London on his new research on pterosaurs and spinosaurs, Dean Lomax about his new research on ichthyosaurs and his latest book, and Luke Muscutt of Imperial on his swimming plesiosaur robot. 

The Fossils Files are on Tour! Susie and Rob are in Birmingham for the massive Society of Vertebrate Paleontology conference which has made a rare trip to Europe. We will be meeting and chatting with palaeontologists from all over the world and bringing you the latest discoveries and hot gossip. On day 1 we join the Nanotyrannus craze and chat to co-author of that study, James Napoli of Stoney Brook NY. The amazing "Duelling Dinos" specimen has been released the world by the North Carolina Museum of Natural Sciences and has sent dinosaur fans aflutter with its implications for tyrannosaurs. We also catch with Yara Haridy of the University of Chicago. She has been revealing lots of new insights into vertebrate origins and evolution with high powered synchrotron analyses. With also catch up Steve Brussatte of the University of Edinburgh as a preview of a longer episode coming up.  For more information on Nanaotyrannus: https://naturalsciences.org/calendar/news/nanotyrannus-confirmed/ And for more information on vertebrate origins, check out our earlier episode "Our deep origins and the vertebrate that wasn't"

A newly discovered fossil from the Cretaceous of Mongolia tells us an interesting story about the purported head butting behaviour of dinosaurs. Pachycephalosaurs are famous for their thick domed heads but it has been disputed how or when this evolved. The beautifully preserved Zavacephale rinpoche has a well preserved skull and dome but also loads of details of the body and tail as well. What is suprising is that this individual is much smaller, and occurs much earlier, than other pachycephalosaurs. We take a look at this new fossil and what this means for interpreting the evolution of dinosaur behaviour.  This week's paper is "A domed pachycephalosaur from the early Cretaceous of Mongolia" by Tsogtbaatar Chinzorig and colleagues from Mongolia and North Carolina, published in Nature in September 2025. https://doi.org/10.1038/s41586-025-09213-6 Wide screen palaeoart by Masaya Hattori.

Cordyceps is a weird fungus that can take over the brain of ants and spiders causing them to go zombie and commit suicide in order to spread disease. Weirder still, some new fossils from the Cretaceous have directly captured this nightmarish behaviour for the first time. We take a look at these interesting fossils, their potentially shady origin story, and their implications for reconstructing evolution of this unsual parasitic behaviour. Side-note: did fungus cause the extinction of dinosaurs? The main paper discussed this week is by Yuhui Zhuang and colleagues "Cretaceous entomopathogenic fungi illuminate the early evolution of insect–fungal associations" published in Proceedings of the Royal Soceiy B in June 2025, (https://doi.org/10.1098/rspb.2025.0407), free version here.    

Discovery of the smallest ever dinosaur acheived quite a splash when it was publised on the front cover of Nature in 2020. The new critter, Oculodentavis, was the size of a hummingbird and reconstructed as close to Archaeopteryx on the lineage to birds. In this episode, Susie and Rob take a look at how this story quickly started to unravel as it turned out Oculodentavis might been something else altogether. This how episode also shed some light on a dark underbelly of an ethical problem for palaeontologists - what if your fossils are coming from a war zone and potentially funding ethic violence?  The main paper discussed this week is by Lida Xing and Jingmai O'Connor and colleagues "Hummingbird-sized dinosaur from the Cretaceous period of Myanmar" published in Nature in 2020, now retracted (https://doi.org/10.1038/s41586-020-2068-4). A brief accessible summary of what happened afterwards can be found here by Krister Smith in Current Biology "It's a bird, it's a plane, it's Oculudentavis!" (https://doi.org/10.1016/j.cub.2021.06.017). A summary of the situation with Myanmar amber fossils including discussion of the paper by Emma Dunne and colleagues can be found in Science "Violent conflict in Myanmar linked to boom in fossil amber research, study claims" by Rodrigo Pérez Ortega (doi:10.1126/science.adf0973) Wide screen palaeoart by Stephanie Abramowicz.

In the first of two episodes on notorious fossil fails, Rob and Susie take a look at how a serious case of mistaken identify unfolded for some Ediacaran 'fossils'. Herein lies a cautionary tail for all relating to pareidolia: our very human tendency to perceive patterns in random shapes and lines, or why we might see jesus is a piece of toast or a smiley face in a cut pepper. This takes us to unexpected destination for hunting for dinosaur fossils: the moon! Image 1: A look at some 'Ediacaran fossils' from the Bhimbetka cave in India and some other structures found there. Image 2: "Fossilised embryo of a dinosaur inside the egg on the moon". Yes you read that right. The main papers discussed this week is by Greg Retallack and colleagues "Dickinsonia discovered in India and late Ediacaran biogeography" published in Gondwana Research in 2021 (https://doi.org/10.1016/j.gr.2020.11.008) with follow up articles by Joseph Meert and colleagues "Stinging News: 'Dickinsonia' discovered in the Upper Vindhyan of India not worth the buzz" published in Gondwana Research in 2023 (https://doi.org/10.1016/j.gr.2023.01.003) and SK Pandey and colleagues "Dickinsonia tenuis reported by Retallack et al. 2021 is not a fossil, instead an impression of an extant 'fallen beehive'" published in 2023 in the Journal of the Geological Society of India (https://doi.org/10.1007/s12594-023-2312-2). The final paper is by Hari Mohan Saxena and Jagmohan Saxena "Dinosaur eggs with fossilized embryos on the moon" 'published' in the New York Science Journal (http://www.dx.doi.org/10.7537/marsnys160823.030). Wide screen Ediacaran image by John Sibbeck.

Perhaps the weirdest dinosaur ever has just been described in Nature, by The Fossil Files' own Susie Maidment. In a worldwide EXCLUSIVE*, Susie gives as the unvarnshed truth about how this spikey Jurassic weirdo came to be found, what makes it different, and peek under the hood as to how palaeontological research like this is conducted. The story weaves in the local and scientific communities in Morroco, funding crises, a global pandemic, dodgy fossil collectors, international law, and a lot of hard work.  The paper is "Extreme armour in the world's oldest ankylosaur" by Susannah Maidment and colleagues, published in Nature August 27th, 2025. https://doi.org/10.1038/s41586-025-09453-6 *Not exclusive Widescreen artwork: Matthew Dempsey

This new discovery is WEIRD. Mirasaura (the 'marvellous lizard') has been described from the Triassic of France, and it has mad projections coming out of its back, far longer than its body. We take a look at what these projections were, and were not (i.e. not feathers), their implications for the evolution of integumentary structures, and our own historically bad haircuts. The paper is "Triassic diapsid shows early diversification of skin appendages in reptiles" by Stephan Spiekman and colleagues, published in Nature in July 2025. https://doi.org/10.1038/s41586-025-09167-9 Wide screen art: Gabriel Ugueto

Squid are a really important part of marine ecosystems, but their fossil record is close to non-existent - their squishy bodies are just really unlikely to be fossilised. In this short bonus episode we take a new look at the squid fossil record. 'Digital fossil mining' reveals a massive diversity of squid in Creataceous oceans. How did the scientists do it and what does this mean? The paper is "Origin and radiation of squids revealed by digital fossil-mining" by Shin Ikegami and colleagues of Hokkaido University, Japan. https://doi.org/10.1126/science.adu6248

The origin of our own group, the vertebrates, has received quite the shake up. One of the important fossil players has been found to be an invertebrate imposter, and this completely changes our understanding of this evolutionary episode. We take a look at why and when, and how this boils to down to a interesting question all about teeth. Did our entire skeleton come from teeth on the outside of our bodies, even before jaws existed? Is this why we now get tooth ache?  The paper is "The origin of vertebrate teeth and evolution of sensory exoskeletons" by Yara Haridy and colleagues, published in Nature in May 2025. https://doi.org/10.1038/s41586-025-08944-w Wide screen art: Brian Engh.     

Pterosaurs dominated Mesozoic skies but it has always been a mystery where these flying reptiles came from. This week Susie and Rob discuss Pterosaur controveries and a cool new study that attempts to solve the problem of where and how they originated. How can you do this? By looking at the climate and locations of where pterosaurs lived and their closest relatives - the weird looking lagerpetids -, we can make predictions about how pterosaurs lived, thrived, and died. And maybe even where we should be looking for them... Figure 4 from paper shows the authors predictions where in the Triassic world would have the right climate for Pterosaurs to live (left column) and Lagerpetids to live (right column). The paper is "Climate drivers and palaeobiogeography of lagerpetids and early pterosaurs" published by Davide Foffa and colleauges in Nature Ecology and Evolution, June 2025. https://doi.org/10.1038/s41559-025-02767-8 Widescreen artwork: Gabriel Ugueto

Why do we collect fossils and who were the first fossil collectors? Cretaceious fossils have been found in a cave in Northern Spain alongside the Neanderthals that were living there 46,000 years ago. Were Neanderthals collecting fossils and if so why? This week Susie and Rob examine those claims and discuss fossil collecting and the recent surge in private trade in dinosaur fossils.  Because we are children, we also giggle at possibly one of the earliest fossils collected, the Erfoud Manuport as well as the Makapansgat pebble.  The paper is "Were Neanderthals the First Collectors? First Evidence Recovered in Level 4 of the Prado Vargas Cave, Cornejo, Burgos and Spain" by Marta Navazo Ruiz and colleagues from the University of Burgos. https://doi.org/10.3390/quat7040049 We also go on to discuss the Stegosaur fossil Apex sold, purchased and loaned to the American Museum of Natural History (AMNH) and the sale of a Ceratosaurus fossil by Utah's Museum of Ancient life.