Palaeocast

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.