The Soom Shale is an Ordovician lagerstätte in the Western Cape of South Africa. Whilst it lacks the diversity of organisms seen in other lagerstätten, such as the Burgess Shale or Chengjiang, it more than makes up for it in the fidelity of preservation. The taphonomic pathway to the fantastic preservation in the Soom Shale is long and complex, reliant not only on local conditions, but also ties into global climatic events. It’s vitally important when interpreting fossils to understand the taphonomy as it provides so much context as to what you can see in fossils and, as equally important, what you can’t. Joining us for this episode is Prof. Sarah Gabbott, a taphonomist from the University of Leicester, UK.

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Episode 119: The Soom Shale

Piecing together the early lives of dinosaurs is difficult due to a lack of fossils from juvenile and embryonic stages. In this episode, Elsa Panciroli talks to Dr Kimi Chappelle, a postdoctoral fellow at the Evolutionary Studies Institute, part of the University of Witwatersrand in Johannesburg, South Africa. Chappelle specialises in sauropodomorphs – the precursors of the giant sauropod dinosaurs like Diplodocus. Her recent work is helping build a picture of their growth and development. Chappelle is a champion of South African palaeontology and nominated as one of the Mail and Guardian’s top 200 young South Africans in Science and Technology. With her colleagues she has published a stunning new study of sauropodomorph embryos from a fossil nest site in South Africa. This new paper visualises and describes their tiny skulls using synchrotron scan data. These fossils provide new information on dinosaur developmental processes, and places South African fossils at the heart of our understanding of their early evolution. Chappelle also talks about the latest work she’s involved with in Zimbabwe, and future research into the growth patterns of the largest dinosaurs to have ever lived.

Episode 118: South African Sauropodomorphs

Lack of diversity is one of the major issues in the sciences in recent times. We’ve discussed diversity in palaeontology in previous podcasts, but in this episode Elsa takes a look at the legacy of racism and colonialism in palaeontology and museum collections, and what efforts are being made to address these issues. Colonial attitudes towards people of non-European descent have meant that their natural heritage was often plundered and sent back to Europe and the United States to fill museum shelves. Researchers continue to benefit from these resources. How should we change our scientific practice to recognise this legacy and avoid making the same mistakes now and in the future? In the first part of the episode, Elsa speaks to Christa Kuljian, a historian of science and author of Darwin’s Hunch, based at the University of the Witwatersrand in Johannesburg. She’ll examine the legacy of racism in science, focusing on palaeoanthropology in South Africa, including figures like Robert Broom and Raymond Dart. We’ll hear how attitudes toward different races shaped the research and conclusions of past generations of scientists. In the second part, Rob Theodore, Exhibitions and Displays Coodinator at the Sedgewick Museum in England, talks about the legacy of colonialism in museum collections. We’ll find out about the ways in which specimens were collected in the past, and how this was related to contemporary events and attitudes. We’ll also find out what moves being taken to decolonise museums and refocus public outreach to recognise the past and move positively into the future.

Episode 117: Decolonising Palaeontology

When we think about the Ice Age or the Pleistocene, we generally think of large animals: wooly mammoths trudging through snow, sabre-tooth tigers taking down their next meal, and big bison out on the steppes. These are really interesting things to think about, but what else can we learn from the Pleistocene other big animals and their extinction? We can also use the Pleistocene (which is relatively similar to the modern world in terms of continental layout, landscapes, and ecological niche availability) to explore questions of palaeoecology, biotic interactions and how changes in the environment can affect the local fauna. The relatively young age of the Pleistocene means that the available data is very different to palaeoecological studies of the Cretaceous or Eocene. This means that it is more appropriate for drawing comparisons to what's happening today or what might happen in the future with climate change. Joining us in this interview is Dr Jacquelyn Gill, an Associate Professor at the University of Maine, who works in palaeoecology. We talk about the different data available, the importance of understanding palaeoecology, including a recent paper from her group on seabird ecology in the Falklands, and what this might mean for the future.

Episode 116: Ice Age Palaeoecology

Part 2. Diatoms are a major group of algae found in waters all around the world. As photosynthetic phytoplankton, they are hugely important ‘primary producers’, integral to nearly every aquatic food chain. They are responsible for a large proportion of the world’s oxygen production, with estimates ranging between 20 and 50%. Diatoms are unicellular plants that produce their cell walls, termed frustules, out of silica. These intricate frustules are what we find preserved in the fossil record and they can contain an absolute wealth of information. In this interview, Prof. Anson Mackay, University College London, joins to discuss his work on the diatoms from Lake Baikal, Siberia. We learn why lakes are such special ecosystems and what diatoms can tell us about the world through studies of their palaeoproductivity over thousands of years.

Episode 115b: Diatoms of Lake Baikal

Diatoms are a major group of algae found in waters all around the world. As photosynthetic phytoplankton, they are hugely important ‘primary producers’, integral to nearly every aquatic food chain. They are responsible for a large proportion of the world’s oxygen production, with estimates ranging between 20 and 50%. Diatoms are unicellular plants that produce their cell walls, termed frustules, out of silica. These intricate frustules are what we find preserved in the fossil record and they can contain an absolute wealth of information. In this interview, Prof. Anson Mackay, University College London, joins to discuss his work on the diatoms from Lake Baikal, Siberia. We learn why lakes are such special ecosystems and what diatoms can tell us about the world through studies of their palaeoproductivity over thousands of years.

Episode 115a: Diatoms of Lake Baikal

Part 2 of 2. The horseshoe crabs (Xiphosura) are a group of large aquatic arthropods known from the East coast of the USA, and the Southern and Eastern coasts of Asia. Despite their name, they are not actually crabs at all, but are chelicerates (the group containing spiders and scorpions). As a group, the horseshoe crabs possess an extremely long fossil record, reaching as far back as the Ordovician Period, some 480 million years ago. Since that time, they would appear to have undergone very little change, leading the horseshoe crabs to become the archetypal ‘living fossils’. Joining us for this two-part episode is Dr Russell Bicknell, University of New England, Australia. We discuss what makes a horseshoe crab, before taking questions from our listeners as to all aspects of horseshoe crab ecology and what we can infer from them about other extinct arthropods.

Ep114b: Horseshoe Crabs

The horseshoe crabs (Xiphosura) are a group of large aquatic arthropods known from the East coast of the USA, and the Southern and Eastern coasts of Asia. Despite their name, they are not actually crabs at all, but are chelicerates (the group containing spiders and scorpions). As a group, the horseshoe crabs possess an extremely long fossil record, reaching as far back as the Ordovician Period, some 480 million years ago. Since that time, they would appear to have undergone very little change, leading the horseshoe crabs to become the archetypal 'living fossils'. Joining us for this two-part episode is Dr Russell Bicknell, University of New England, Australia. We discuss what makes a horseshoe crab, before taking questions from our listeners as to all aspects of horseshoe crab ecology and what we can infer from them about other extinct arthropods.

Ep114a: Horseshoe Crabs

 With palaeontology as popular as it is you will never be short of content online, whether that be articles, blogs, podcasts (of which there are now many others you should also be listening to) or videos. This allows you, the public, to enjoy learning about past life on demand and in a format that best suits you. The only issue with having so many sources of information/entertainment is that the quality can be highly variable and it can be difficult to determine whether any given outlet/channel values more the accurate communication of palaeontological science or the number of viewers/ad revenue they get. Amongst some notable exceptions to this issue is the YouTube channel PBS Eons, who have produced a hugely successful series that also stands up to scientific scrutiny. In this interview, we're joined by Eons host Kallie Moore who discusses everything to do with the show, from how it is researched and shot, to the benefits of using YouTube for outreach. 

Episode 113: PBS Eons

The end-Cretaceous (or K-Pg) extinction is one of the best known mass extinctions in Earth's history, primarily because that is when non-avian dinosaurs disappeared. Although the popular idea is that an asteroid impact was what caused the extinction, the science hasn't actually been that clear. More recently, a second hypothesis has challenged the idea asteroid as the main culprit, suggesting that huge volcanic eruptions in what is now India called the Deccan Traps was responsible. It has also been suggested that dinosaurs were already in decline when these things happened, speeding up the inevitable. In this interview, we speak with Dr Alessandro Chiarenza, a research associate at University College London about his new paper published today in PNAS showing that it really was the asteroid impact that killed the dinosaurs. This new study, based on research he did during his PhD at Imperial College London, uses a large amount of data put into climatic models to analyse different scenarios caused by an asteroid impact, the Deccan Traps volcanism, and a combination of the two. This study showed that the asteroid caused a prolonged impact winter, causing the extinction of the dinosaurs.

Episode 112: Extinction of the dinosaurs

In this episode, in conjunction with the Society of Vertebrate Paleontology (SVP), we investigate issues of diversity in palaeontology, through interviews with Jann Nassif (PhD student at Ohio University, USA) on being transgender in palaeontology; Professor Taissa Rodrigues (Universidade Federal do Espírito Santo, Brazil) and Dr Femke Holwerda (Dr Betsy Nicholls Postdoctoral Research Fellow at the Royal Tyrrell Museum of Palaeontology, Canada) about women in palaeontology; and Gabriel-Philip Santos (Collections Manager and Outreach Coordinator at the Raymond M. Alf Museum of Paleontology at The Webb Schools) about racial diversity. We also spoke with Professor Jessica Theodor (University of Calgary), the Vice President of SVP about what they are doing to increase diversity and address these issues. This episode was recorded in 2019 at the SVP meeting in Brisbane, Australia, but for several reasons has taken us a little while to complete. Given the current discussions and anti-racism activism going on around the world, we thought this was a good time to reflect on some of the issues within our science and the ways in which they are being addressed.

Episode 111: Diversity in Palaeontology

One of the great themes in palaeobiology is the water-land transition, or how and when the ancestors of today’s four-legged terrestrial animals moved to land. Lines of questioning have included understanding the anatomy and biomechanics of the axial skeleton- head and vertebrae (focusing on biting and swallowing) and the appendicular skeleton (focusing on how the earliest tetrapods walked or swam). Our picture of this story has drastically changed in the last three decades, as new fossils have filled in crucial gaps in the tetrapod evolutionary tree. This changing picture really came to the fore with the work of the late Professor Jenny clack, who’s work at Cambridge in early tetrapods from Greenland and elsewhere  brought the water land question back in fashion.  Joining us to discuss Jenny Clack's Legacy in this episode are Prof. Mike Coates and Ben Otoo both of the University of Chicago. 

Episode 110: The Fin-Limb Transition and Early Tetrapod Biodiversity

Early tetrapods include the earliest animals to grow legs, and their closest ancestors. Moving from the water to land required a number of changes within the skeleton and muscular system, related to moving from swimming to crawling, greater pressure on the body after experiencing further effects of gravity without buoyancy, and the difference in feeding with and without water. This transition is commonly referred to as the 'water-to-land' transition. While a significant amount of work has been done on the anatomical changes through this period, there has been less study on the biomechanics. What has been looked at tends to relate to the mechanical changes related to walking on land and the limbs. However, less has been done looking at the skull mechanics and feeding. Early tetrapod work was pioneered by Professor Jenny Clack. She did a lot of early field work and description, understanding this transition better than anyone. Sadly, Professor Clack passed away in March, but has left behind a legacy of other professors, post docs and students around the globe which she inspired. In this episode, we talk to Dr Laura Porro from University College London about her work on early tetrapod feeding and skull mechanics, and how the skull changed over the water-to-land transition, work which was done with and inspired by Jenny.

Episode 109: Early Tetrapod Feeding Mechanics

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Plesiosaurs are some of the most easily recognisable animals in the fossil record. Simply uttering the words ‘Loch Ness Monster’ can conjure a reasonably accurate image of what they look like. Thanks to palaeoart, it’s also fairly easy to envision how they lived: swimming through the open Jurassic seas, picking fish, ammonites and belemnites out of the water. What we don’t imagine are plesiosaurs at the South Pole, nor would we ever picture them swimming amongst icebergs or poking their heads out of holes in the ice to breathe. We’d never think to find them in freshwater either. Even more surprising is that the evidence for this radical vision of polar plesiosaurs is found preserved in the precious mineral opal. In this interview, we’re joined by Dr Benjamin Kear, Curator of Vertebrate Palaeontology at the Museum of Evolution, Uppsala University in Sweden. He paints for us a picture of life at the South Pole and the importance of polar habitats in driving the evolution of the plesiosaurs.

Episode 108: Plesiosaurs

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