Favourite science writing: Sleeping with Neanderthals

It helps that it's an utterly intriguing subject: what defines us as human? But really, Elizabeth Kolbert could make anything interesting, and this feature-length article, ostensibly about the attempt to sequence the Neanderthal genome, uses her trademark personal insight and riveting narrative style.

Kolbert so skillfully manages the tricky task of weaving several concurrent stories through the one feature, that the reader is hardly aware of the jumps in a long piece that flows without crossheads or text-breakouts. Through it, she includes a profile of palaeogeneticist Svante Pääbo, the unfolding genetic and developmental story of human evolution, and the creation of fast-throughput genetic analysis, all infused within the central philosophical and scientific question of what it means to be human. Why are we so special? What enabled us to take over the world while our cousins are caged in zoos or extinct?

She begins the piece with a report from Leipzig in Germany, immediately contrasting Pääbo's cutting-edge research facility with the city's Soviet-era buildings and the ape cages at Leipzig zoo. Within the first paragraph, she has shown us the different ways we've lived in the space of just one generation, and how it is starkly at odds to the lot of our living ape cousins. It's a device she continues to wield to great effect throughout the piece.

A sympathetic portrait of Pääbo reveals him to be a remarkable character, and certainly this reader is rooting for him as he attempts this extraordinary task in the face of crushing setbacks: we're told that the nucleotides that make up DNA start to disintegrate in the first hours after death, and certainly within 5,000 years, but that Neanderthals went extinct more than 30,000 years ago; we learn of early exaltations before the realisation that the DNA he's sequenced was contaminated with human – perhaps his own – DNA; and his shocking discovery that all non-Africans alive today contain a significant portion of Neanderthal DNA in our genomes.

In other words, they were so similar to us that we desired them. We shared our beds with them and produced half-Neanderthal, half-human children.

Kolbert takes us on a philosophical tour of the early responses to the first discoveries of Neanderthal remains in the early 20th century - they were described as hairy beasts, with the differences between them and us exaggerated – to her visit to a Neanderthal cave dwelling, where she handles the tools they crafted; to the zoo, where she watches apes and children performing tasks set by researchers to reveal their intelligence. Through it all, she makes it impossible not to feel the same recognition and empathy for these creatures as one more usually directs at our fellows.

So, what makes us human? The answer, according to Pääbo, may be some sort of gene for "madness" that sent us on a trajectory of exploration that led to Moon voyages, but left our relatives in their mundane, unchanged lives. "If we one day know that some freak mutation made the human insanity and exploration thing possible, it will be amazing to think that it was this little inversion on this chromosome that made all this happen and changed the whole ecosystem of the planet and made us dominate everything," he says.

Gaia Vince is a freelance science reporter based in London. She blogs at Wandering Gaia

Enter the Wellcome Trust Science Writing Prize in association with the Guardian and the Observer