Palaeocast – Détails, épisodes et analyse

The iguanodontians were an incredibly successful group within the Cretaceous. They could reach incredible sizes, with the largest species even matching the proportions of some sauropods, and they also had an incredible palaeogeographic range, meaning that their remains are found all over the world today. In the late Jurassic, they were a lot less diverse and much smaller, so the late Jurassic and early Cretaceous are key times for understanding the evolution of this group.

Cariocecus bocagei is a newly described iguanodontian from the Early Cretaceous of Praia do Areia do Mastro, Portugal. Whilst it is only know from a partial skull, there are numerous useful characteristics that help identify it as a new species and fill in our understanding of iguanodontians in this important time in their evolution.

Joining us in this episode is Dr Filippo Bertozzo of the Royal Belgian Institute of Natural Sciences.

Found in the fossil record between the Jurassic and the middle Miocene, Notosuchia was a highly diverse and strange group of crocodylomorphs, most notable for their terrestrial lifestyle.

Joining us for today's episode is Dr Yohan Pochat-Cottilloux from the Laboratoire de Géologie de Lyon, who specialises in the study of crocodylomorphs. Together, we will explore the wide range of scientific methodologies that have so far been used to study the lives of these strange reptiles and discuss how they may have looked and behaved.

The Ediacaran Period is host to the first large and complex multicellular organisms known in the fossil record. This 'Ediacaran Biota' has long eluded definitive placement on the tree of life, seemingly falling between even the most fundamental of its branches. At the core of this taxonomic issue are their unique body plans, not seen replicated in any other kingdom.

Amongst the researchers trying to unravel the mystery of these organisms is Dr Frances Dunn of the University of Oxford. Frankie has been researching the developmental biology of the Ediacaran Biota in the hope that we can learn more from how these forms grew, as opposed to what they eventually grew into.

Terror birds, or phorusrhacids as they are known scientifically, are a group of large, flightless birds that lived during the Cenozoic, and truly lived up to their name. Known for their large, powerful skulls, and enormous beaks, these birds are unlike the flightless birds we have alive today. Despite their strange appearance and unique morphology, terror birds aren't well known in popular culture. What were they doing? How big did they get? What did they eat?

In this episode, we talk to a leading terror bird expert, Dr Federico "Dino" Degrange from the Centro de Investigaciones en Ciencias de la Tierra (CICTERRA) in Córdoba, Argentina to get answers to these questions. We discuss some of his recent research, and what we know (and don't know) about phorusrhacids today.

Between the weird and wonderful rangeomorphs of the Ediacaran Period and the world-famous palaeocommunities of the Burgess Shale, the 'Early Cambrian' is host to a 'waste basket' of fossils untied by their small size and shelly construction.

These small shelly fossils (SSFs) aren't just a single group of animals, but represent several different invertebrate phyla. Further compounding the difficulty of their identification, each SSF, termed a 'sclerite', is part of a larger composite skeleton known as a 'sclerotome'. Whilst some complete sclerotomes have been preserved, many SSFs still represent multiple jigsaws thrown together and the pictures lost.

Piecing the SSFs back together and building a picture of the Earliest Cambrian is Dr Marissa Betts of the University of New England, Australia. Her work on the SSFs have provided a new framework for the regional stratigraphy of Australia and in this interview, we discuss why this was necessary, how she went about it and finally, what we know about the animals themselves.

Between the weird and wonderful rangeomorphs of the Ediacaran Period and the world-famous palaeocommunities of the Burgess Shale, the 'Early Cambrian' is host to a 'waste basket' of fossils untied by their small size and shelly construction.

These small shelly fossils (SSFs) aren't just a single group of animals, but represent several different invertebrate phyla. Further compounding the difficulty of their identification, each SSF, termed a 'sclerite', is part of a larger composite skeleton known as a 'sclerotome'. Whilst some complete sclerotomes have been preserved, many SSFs still represent multiple jigsaws thrown together and the pictures lost.

Piecing the SSFs back together and building a picture of the Earliest Cambrian is Dr Marissa Betts of the University of New England, Australia. Her work on the SSFs have provided a new framework for the regional stratigraphy of Australia and in this interview, we discuss why this was necessary, how she went about it and finally, what we know about the animals themselves.

Fossilisation of organic material was long thought to result in the complete loss of original content. However in the last 20 years, several high-profile publications reported the discovery of proteins, blood vessels, blood cells and even DNA. But for as long as these arguments have existed, so too has a counterargument as to the validity of the discoveries.

In this episode, we're joined by Dr Evan Saitta of the Field Museum of Natural History, Chicago, lead author of a recent paper seeking to discover and evaluate the preservation of putative original organic materials within dinosaur bones.

One of palaeontology's great themes of questioning is the rise of novelty: how new structures and functions arise in specific lineages. In this episode we speak with Neil Shubin, Professor of Organismal Biology at the University of Chicago, who has been studying novelty in the context of the vertebrate transition from water to land.

Neil studies the fossil record of early tetrapods, the first vertebrates with limbs, to understand what changes underpinned this great transition. The other half his lab uses molecular techniques on living organisms to see how changes to the development of appendages (and their underlying genetic architecture) effected the shift from a fin to a limb.

In this interview, we hear about his fieldwork in the Arctic and Antarctic, how palaeontologists decide where to look for key fossils, why development matters, and about his deep involvement in science communication.

Undoubtedly, Megalodon is the world's most famous extinct shark is and in this episode, we hear everything we know about this taxon, its ecology and how it got to be so big. Its ultimate extinction is also considered, not in isolation, but placed in the wider context of the entire marine ecosystem.

Joining us is Dr Catalina Pimiento of  Swansea University.