The Fossil Files

Why did T. rex have such small arms? Revealed

Tyrannosaurus rex is perhaps the most famous dinosaur and maybe even the most famous fossil animal. It has long been a source of curiosity as to why is has such small arms though. What could the possible function be? This week we take a look at a new paper has taken a quantitative approach to this age long-thorny problem to investigate the evolutionary changes that might have led to such unusual anatomy. Indeed it happened not just one, but five times in the theropods. Let's find out why and how! This week's paper is "Drivers and mechanisms of convergent forelimb reduction in non-avian theropod dinosaurs" by Charlie Scherer and colleagues published in Proceedings of the Royal Society in May 2026. https://doi.org/10.1098/rspb.2026.0528 [https://doi.org/10.1098/rspb.2026.0528] Wide screen art by Arvalis/Saurian.

Digging for dinosaurs and the battle against poaching: Susie reports from the field [Preview]

Digging up dinosaur fossils is a complicated and unpredictable business. But how does it feel to be one of the scientists on the ground doing the exploring? What can you do when you are in a race to find dinosaur fossils before they are extracted and lost to the black market? In this episode Susie is in the field in Morocco to report the trials and tribulations of the team's dino hunting seasons. She takes us on a journey from exciting new dinosaur finds, disappointing setbacks when their quarry was raided, and their work with the local and national authorities to get the site protected for future generations. This is a preview of one of our bonus episode, the full version of which is available on our patreon for subscribers https://www.patreon.com/cw/FossilFiles [https://www.patreon.com/cw/FossilFiles] In this episode we hear from the team which includes Ahmed Oussou and Kawtar Ech-Charay of Sidi Mohamed Ben Abdellah University Fez, Richard Butler from the University of Birmingham, and Simon Wills and Pim Kaskes from the Natural History Museum London. You can find out more about Susie's work in episode 9, "The Spicomellus special".

The Fossil Files is one year old: The best bits so far

The Fossil Files is one year old! Thank you everbody for your support! To mark the occasion, Susie and Rob take a look back at the last year and put together some of their favourite moments to highlight the best of The Fossil Files (so far) The episodes covered are: Episode 10. Fossil Fails: A Precambrian beehive and dinosaurs on the moon (September) Episode 3. Is de-extinction a scam? (July) Episode 6. Where did Pterosaurs come from? (August) Episode 12. Cretaceous zombie ants (October) Episode 9. The Spicomellis special (September) Episode 5. Were Neanderthals the first fossil collectors? (July) Episode 19. Dinosaurs were doing fine (before the asteroid), with Steve Brusatte (December) Episode 17. AI & the future of palaeontology (December) Episode 2. Dinosaur poos from Poland (June) Episode 20. Back-breaking and baby making, the disturbing bedroom habits of hadrosaurs (January) Episode 28. How to get a Species of Human Named after you (March) Episode 32. Were giant super intelligent octopuses the top predators of the Cretaceous? (May)

The Mysterious Devonian Giant that may be an unknown branch of life

400 million years ago, before the rise of forests, the land was covered in mossy carpets, loomed over by weird 8 meter tall columns called Prototaxites. These weird giants have long been thought to be some sort of fungus body, slowly digesting rotting matter. A new paper has taken a detailed look at some well preserved fossils from the Devonian of Scotland and reveals that this enigmatic giant wasn't a fungus, wasn't a plant, wasn't an animal, and wasn't a bacterium... it was something else. This week Susie and Rob take a look at the strange world of the Devonian giant Prototaxites and speculate what it might, or might not, have been. In other fungus news, we also take a look at a paper using fungal microfossils to suggests that dinosaur extinction could have been a multi-phase event, before and after the asteroid impact at the end of the Cretaceous. The main paper discussed this week is "Prototaxites fossils are structurally and chemically distinct from extinct and extant Fungi" by Corentin Loron and colleagues from the University of Edinburgh, published in Science Advances in January 2026 https://doi.org/10.1126/sciadv.aec6277 [https://doi.org/10.1126/sciadv.aec6277] The other paper is "Fungal proliferation before and after the Cretaceous–Paleogene mass extinction event in North America" by Rosanna Baker and colleagues published in PNAS in May 2026 Fungal proliferation before and after the Cretaceous–Paleogene mass extinction event in North America https://doi.org/10.1073/pnas.2536899123 [https://doi.org/10.1073/pnas.2536899123] Wide screen art by M Humpage

Were giant super intelligent octopuses the top predators of the Cretaceous?

Cretaceous oceans have long been accepted as a dangerous place full of massive mosaurs and other predators. Now some new fossils from Japan have upended this with the suggestion that the "top dog" was not any vertebrate, but instead giant octopuses that were far larger than any invertebrates alive today. This has generated a lot of Kraken related headlines (and social media posts), but is everything as it seems? This week Susie and Rob take a look at these claims and ask: were super intelligent giganto-octopuses the top predators in Cretaceous? Get your salt shaker to hand, because you mind need to take it with a pinch of salt. This weeks paper is "Earliest octopuses were giant top predators in Cretaceous oceans" by Shin Ikegami and colleagues published in Science in April 2026 https://doi.org/10.1126/science.aea6285 [https://doi.org/10.1126/science.aea6285] Another paper mentioned is "Synchrotron data reveal nautiloid characters in Pohlsepia mazonensis, refuting a Palaeozoic origin for octobrachians" by Thomas Clements and colleagues, published in Proceedings of the Royal Society B in April 2026 https://doi.org/10.1098/rspb.2025.2369 [https://doi.org/10.1098/rspb.2025.2369] Widescreen art by HodariNundu