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 tendancy 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!

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.