Elephants are the largest living land mammal and today our planet is home to three species: the African bush elephant, the African forest elephant, and the Asian elephant.

But a hundred thousand years ago, in the chilly depths of the Ice Age, multiple species of elephant roamed the earth: from dog-sized dwarf elephants to towering woolly mammoths.

These gentle giants' evolutionary story and its parallels with that of humankind has long fascinated Dr Tori Herridge, a senior lecturer in evolutionary biology at the University of Sheffield, where - as a seasoned science broadcaster - she's also responsible for their Masters course in Science Communication.

Tori has spent much of her life studying fossil elephants and the sites where they were excavated; trying to establish facts behind relics that are far beyond the reach of Radio Carbon Dating. To date she's discovered dwarf mammoths on Mediterranean islands, retraced the groundbreaking Greek expedition of a female palaeontologist in the early 1900s, and even held an ancient woolly mammoth’s liver. (Verdict: stinky.)

But as she tells Professor Jim Al-Khalili, this passion for fossil-hunting is not just about understanding the past: this information is what will help us protect present-day elephants and the world around them for future generations.

Presented by Jim Al-Khalili