How have the evolutionary forces that shaped animal sex and behaviour influenced the ways humans conserve, study and coexist with other species? As the Zoological Society of London, the precursor to the zoo, celebrates its 200th anniversary, Adam Rutherford is joined by three guests whose work uncovers the scientific, historical and ethical threads connecting humans with the wider animal world.

Biologist Lixing Sun introduces his new book On the Origin of Sex - the Weird and Wonderful Science of how our Planet is Populated, uncovering how mating strategies and reproductive behaviour evolved across species. From Californian Condors to clownfish, the dazzling array of ways in which the animal kingdom procreates is both baffling and astonishing.

Cultural historian Elsa Richardson, from the University of Strathclyde, discusses her latest research into the archives of Edinburgh Zoo, revealing a rich and little‑known record of early zoological observation, public spectacle and the shifting moral landscapes of how people have imagined, displayed and interpreted animal behaviour.

And Sarah Forsyth, Curator of Mammals at ZSL, reflects on the history of the organisation and offers insights into the crucial conservation work that the Zoo is involved in today. From field programmes to breeding initiatives, Sarah explores how modern zoos can help safeguard species and shape our understanding of animals in a rapidly changing world.

Producer: Natalia Fernandez