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, evolve into trees. Since their emergence around 400 million years ago after low lying plants started to develop stronger stems and grow taller and more upright, trees have transformed our planet, so creating ecosystems, altering the atmosphere and setting the stage for the world as we know it today.

With

Jenny McElwain

Christopher Berry

And

Bill Baker

Produced by Conor Garrett

Reading list:

David Beerling: The Emerald Planet: How Plants Changed Earth's History (Oxford University Press, 2008)

C.M. Berry, ‘Palaeobotany: The Rise of the Earth’s Early Forests’ (Current Biology 29, 2019)

Christopher M. Berry and John E.A. Marshall, ‘Lycopsid forests in the early Late Devonian paleoequatorial zone of Svalbard’ (Geology 43:12, 2015)

N.S. Davies, W.J. McMahon and C.M. Berry, ‘Earth’s earliest forest: fossilized trees and vegetation-induced sedimentary structures from the Middle Devonian (Eifelian) Hangman Sandstone Formation, Somerset and Devon, SW England’ (J. Geol. Soc. 181, 2024)

P. Geisen and C.M. Berry, ‘Reconstruction and Growth of the Early Tree Calamophyton (Pseudosporochnales, Cladoxylopsida) Based on Exceptionally Complete Specimens from Lindlar, Germany (Mid-Devonian): Organic Connection of Calamophyton Branches and Duisbergia Trunks’ (International Journal of Plant Sciences 174 (4), 2013)

A. Groover and Q. Cronk (eds), Comparative and Evolutionary Genomics of Angiosperm Trees: Plant Genetics and Genomics (Crops and Models, vol 21. Springer, 2017), especially ‘The Evolution of Angiosperm Trees: From Palaeobotany to Genomics’ by Q.C.B. Cronk and F. Forest

Jennifer McElwain, Marlene Hill Donnelly, and Ian Glasspool, Tropical Arctic: Lost Plants, Future Climates, and the Discovery of Ancient Greenland (University of Chicago Press, 2021)

Harriet Rix, The Genius of Trees: How Trees Mastered the Elements and Shaped the World (Vintage, 2026)

W.E. Stein et al., ‘Mid-Devonian Archaeopteris roots signal revolutionary change in earliest fossil forests’ (Current biology, 30:3, 2020) pp.421-431

William E. Stein, Christopher Mark Berry, Linda VanAller Hernick and Frank Mannolini ‘Surprisingly complex community discovered in the mid-Devonian fossil forest at Gilboa’ (Nature 483, 7387, 2012)

Max Telford, The Tree of Life: Solving Science's Greatest Puzzle (John Murray, 2026)

K.J. Willis, J.C. McElwain, The Evolution of Plants (Oxford University Press, 2014)

James Woodford, The Wollemi Pine: The Incredible Discovery of a Living Fossil from the Age of the Dinosaurs (The Text Publishing Company, 2005)

Alexandre R. Zuntini et al, ‘Phylogenomics and the rise of the angiosperms’ (Nature vol. 629, April 2024)

Spanning history, religion, culture, science and philosophy, In Our Time from BBC 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.