Neanderthal Man: In Search of Lost Genomes

Svante Pääbo is the director of the Department of Genetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. He is one of the founders of the field of paleogenetics and, with his team, was responsible for sequencing the Neanderthal genome in 2010 (the Neanderthal Genome Project). He was awarded the Nobel Prize in Physiology or Medicine in 2022 "for his discoveries concerning the genomes of extinct hominins and human evolution" (according to the Nobel Prize press release).

His book, Neanderthal Man: In Search of Lost Genomes, 2014, relates the story of the years leading up to this achievement, which is written as a personal memoir focusing on the details of the scientific method that was developed.

One of the difficulties the team was confronted with from the start of their work was the limited ancient material for DNA analysis. However, the greatest problem to solve was finding methods for avoiding contamination while extracting ancient DNA from fossils, bones and teeth. The smallest amount of DNA from archaeologists, researchers, or lab technicians would contaminate the ancient DNA and reveal false results. But Pääbo was given enough support to set up his own institute in Leipzig, and his creation of a “clean room” – an isolated laboratory designed to eliminate any possible contamination – is now the standard for working with ancient material. There is quite a detailed description of how this laboratory was eventually developed through trial and error.

Part of the story is about the balance between taking the time for thorough experimenting and the rush to publish the results before another research team does. And Pääbo was very insistent on thorough research and experiments. But in the months leading up to the publication of the paper revealing that the Neanderthal genome had been successfully sequenced, Pääbo was very nervous about a team in California, who he believed was not as thorough, beating him to publication.

Referring to a colleague’s paper about DNA samples from extinct mammoths, Pääbo writes, “Hendrik’s paper also illustrated a dilemma in science: doing all the analyses and experiments necessary to tell the complete story leaves you vulnerable to being beaten to press by those willing to publish a less complete story that nevertheless makes the major point you wanted to make. Even when you publish a better paper, you are seen as mopping up the details after someone who made the real breakthrough.”

While the sequencing of the Neanderthal genome was a significant achievement, the information it has so far revealed about the Neanderthals themselves has also been groundbreaking. Perhaps the most interesting is that it confirmed that there was interbreeding between Neanderthals and Homo sapiens and also with Denisovans (another hominin species discovered through these DNA studies). It has also provided new information about the origins, dwellings, and migration patterns of early hominins, including Homo sapiens.

Throughout the book, there are detailed descriptions of the work being done to search for successful methods to test bone and tooth specimens that could be trusted and reproduced. Some of these descriptions were extremely technical, but Pääbo gives examples to help the non-specialist reader understand what was being done.

Perhaps a minor criticism is the title of the book. First, I don’t understand why it’s called Neanderthal Man, when the information involves all Neanderthals. And, second, the book focuses on Neanderthals only in the last few chapters. Most of the book details the development of the field of paleogenetics and the specific work done by Pääbo’s team. The information learned about Neanderthals (as well as Denisovans) from the sequencing of the genome is only at the end of the book. The book’s subheading, In Search of Lost Genomes, is a better description of the content, but perhaps not as catchy.

That aside, Pääbo ends the book by indicating the further research he and his team have started, and how the method of sequencing ancient genomes is already being used by other scientists. I’m looking forward to further developments to read about.

This book is my choice for the topic of Science for the 2025 Nonfiction Reader Challenge.