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The Mariana Trench

Misha Glenny and guests discuss what explorations are revealing of the life and geology at the bottom of the deepest oceanic trench in the world, much deeper than Everest is high.

Misha Glenny and guests discuss one of the wonders of the natural world. In 1875 in the western Pacific, the crew of HMS Challenger discovered the Mariana Trench which turned out to be deeper than Everest is high, by two kilometres. Trenches like Mariana form when one tectonic plate slips under another and heads down and there are around fifty of them globally. While at one time some thought it was too dark and deep for life there and others wildly imagined monsters, the truth has turned out to be much more surprising.

With

Heather Stewart,
Director of Kelpie Geoscience and Associate Professor at the University of Western Australia

Jon Copley
Professor of Ocean Exploration and Science Communication at the University of Southampton

And

Alan Jamieson
Director of the Deep Sea Research Centre at the University of Western Australia

Producer: Simon Tillotson

Reading list:

Susan Casey, The Underworld: Journeys to the Depths of the Ocean (Doubleday, 2023)

Jon Copley, Deep Sea: 10 Things You Should Know (Orion Books, 2023)

Hali Felt, Soundings: The Story of the Remarkable Woman Who Mapped the Ocean Floor (Henry Holt & Co, 2012)

M.E. Gerringer, 鈥楶seudoliparis swirei: A newly-discovered hadal liparid (Scorpaeniformes: Liparidae) from the Mariana Trench鈥� (Zootaxa 4358 (1), 161-177, 2017)

A.J. Jamieson, The Hadal Zone: Life in the Deepest Oceans (Cambridge University Press, 2015)

A.J. Jamieson et al., 鈥楢 global assessment of fishes at lower abyssal and upper hadal depths (5000 to 8000 m)鈥� (Deep-Sea Research Part 1. 178: 103642, 2021)

A.J. Jamieson et al., 鈥楩ear and loathing of the deep ocean: Why don鈥檛 people care about the deep sea?鈥� (ICES Journal of Marine Science. 78: 797-809, 2020)

A.J. Jamieson et al., 鈥楳icroplastic and synthetic fibers ingested by deep-sea amphipods in six of the deepest marine environments on Earth鈥� (Royal Society Open Science, 6, 180667, 2019)

A.J. Jamieson et al., 鈥楤ioaccumulation of persistent organic pollutants in the deepest ocean fauna鈥� (Nature Ecology and Evolution. 1, 0051, 2017)

V.L. Vescovo et al., 鈥楽afety and conservation at the deepest place on Earth: A call for prohibiting the deliberate discarding of nondegradable umbilicals from deep-sea exploration vehicles鈥� (Marine Policy. 128, 104463, 2021)

J.N.J. Weston et al., 鈥楴ew species of Eurythenes from hadal depths of the Mariana Trench, Pacific Ocean (Crustacea: Amphipoda)鈥� (Zootaxa. 4748(1): 163-181, 2020)

In Our Time is a 麻豆社 Studios Production

Spanning history, religion, culture, science and philosophy, In Our Time from 麻豆社 Radio 4 is essential listening for the intellectually curious. In each episode, host Misha Glenny and expert guests explore the characters, events and discoveries that have shaped our world.

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58 minutes

Last on

Sun 25 Jan 2026 23:00

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of the University of Southampton

of the University of Western Australia听

of the University of Western Australia听


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Broadcasts

  • Thu 22 Jan 2026 09:00
  • Sun 25 Jan 2026 23:00

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