In Our Time28 Kesä 2007

The Permian-Triassic Boundary

Melvyn Bragg and guests discuss the Permian-Triassic boundary. 250 million years ago, in the Permian period of geological time, the most ferocious predators on earth were the Gorgonopsians. Up to ten feet in length, they had dog-like heads and huge sabre-like teeth. Mammals in appearance, their eyes were set in the side of their heads like reptiles. They looked like a cross between a lion and giant monitor lizard and were so ugly that they are named after the gorgons from Greek mythology – creatures that turned everything that saw them to stone. Fortunately, you’ll never meet a gorgonopsian or any of their descendants because they went extinct at the end of the Permian period. And they weren’t alone. Up to 95% of all life died with them. It’s the greatest mass extinction the world has ever known and it marks what is called the Permian-Triassic boundary. But what caused this catastrophic juncture in life, what evidence do we have for what happened and what do events like this tell us about the pattern and process of evolution itself?With Richard Corfield, Senior Lecturer in Earth Sciences at the Open University; Mike Benton, Professor of Vertebrate Palaeontology in the Department of Earth Sciences at the University of Bristol; Jane Francis, Professor of Palaeoclimatology at the University of Leeds

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Seashells

Misha Glenny and guests discuss a familiar feature of our beaches: seashells, from their astonishing shapes and patterns that teach us about Earth’s oceans, to the ways that humans have treasured shel...

30 Heinä 53min

Vigée Le Brun

Misha Glenny and guests discuss the French portrait painter Élisabeth Vigée Le Brun (1755 - 1842). From her teens she delighted her high society subjects in and around Paris, notably Marie Antoinette ...

23 Heinä 56min

The Delian League

Misha Glenny and guests discuss the origins and evolution of an alliance which transformed the geopolitics of the classical world: the Delian League. Since the start of the 5th Century BCE, city state...

16 Heinä 54min

Machado de Assis

Misha Glenny and guests discuss one of the towering figures of Brazilian and world literature, Machado de Assis (1839 - 1908). He was the descendant of slaves and built his career while slavery was s...

9 Heinä 53min

The Global Story - The soft power superpower, with Roman Mars

As 4th July approaches, we think you’ll like this episode of The Global Story. All week, The Global Story podcast is exploring the surprising and often hidden ways the US has shaped the modern world. ...

3 Heinä 27min

The Evolution of Trees

Misha Glenny and guests discuss the earliest evidence we have of the existence of trees and how even plants we might have on windowsills or as vegetables in gardens can and do, in the right conditions...

2 Heinä 54min

The Welsh Marches

At the Hay Festival, Misha Glenny and guests discuss the impact of the Norman invasion on the people and land of Wales and across the modern border with England in what became known as The Welsh March...

25 Kesä 52min

The Levellers

Misha Glenny and guests discuss the group which came to be known as the Levellers and emerged during what would become arguably one of the bloodiest and most turbulent periods of English history. Afte...

18 Kesä 55min