Sam's guest on this week's Book Club podcast is the palaeobiologist Thomas Halliday, whose book Otherlands: A World In The Making takes us on an extraordinary journey through the whole history of life on earth. Thomas tells Sam why tyrannosaurus rex didn't eat diplodocus, why if you had to live in a swamp the carboniferous might be a good time to do it, and gives a jaw-dropping sense of what the night sky looked like when the earth was young.
