In this episode from our centenary series exploring 100 ideas in genetics, we’re uprooting the tree of life - asking whether we should believe our eyes or our sequencing machines when it comes to deciding what makes a species. Plus, the greatest comebacks of all time - we look at the science of de-extinction and find out whether Jurassic Park could ever become a reality. Full show notes, transcript, music credits and references online at GeneticsUnzipped.com) Follow us on Twitter @GeneticsUnzip) Genetics Unzipped is written and presented by Kat Arney with additional research by Emily Nordvang, and produced by First Create the Media )for the Genetics Society) - one of the oldest learned societies in the world dedicated to supporting and promoting the research, teaching and application of genetics. Production by Hannah Varrall.