The Fish-Tetrapod Transition

The Fish-Tetrapod Transition

Author: BBC Radio 4 November 17, 2022 Duration: 55:33

Melvyn Bragg and guests discuss one of the greatest changes in the history of life on Earth. Around 400 million years ago some of our ancestors, the fish, started to become a little more like humans. At the swampy margins between land and water, some fish were turning their fins into limbs, their swim bladders into lungs and developed necks and eventually they became tetrapods, the group to which we and all animals with backbones and limbs belong. After millions of years of this transition, these tetrapod descendants of fish were now ready to leave the water for a new life of walking on land, and with that came an explosion in the diversity of life on Earth.

The image above is a representation of Tiktaalik Roseae, a fish with some features of a tetrapod but not one yet, based on a fossil collected in the Canadian Arctic.

With

Emily Rayfield Professor of Palaeobiology at the University of Bristol

Michael Coates Chair and Professor of Organismal Biology and Anatomy at the University of Chicago

And

Steve Brusatte Professor of Palaeontology and Evolution at the University of Edinburgh

Producer: Simon Tillotson


Melvyn Bragg and a panel of academic experts gather each week to explore the vast history of scientific thought on In Our Time: Science. This BBC Radio 4 podcast delves far beyond simple explanations, instead tracing the long and often winding paths of discovery that shaped our understanding of the world. Each episode focuses on a single idea, from the concept of zero to the theory of plate tectonics, unpacking its origins, the controversies it sparked, and the key figures who championed or challenged it. You’ll hear lively, in-depth conversations that place science firmly within its human and historical context, revealing how principles we take for granted today were hard-won through centuries of debate, accident, and insight. The discussions are rigorous and accessible, designed for the curious mind eager to appreciate not just what we know, but how we came to know it. By treating science as a deeply historical endeavour, this series offers a richer appreciation of the discipline itself. Tune in for a thoughtful and engaging journey through the experiments, the arguments, and the brilliant flashes of imagination that have defined our quest for knowledge.
Author: Language: English Episodes: 100

In Our Time: Science
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