Missing the Link

Ida, the 47 million-year-old primate fossil, was an important discovery. But not for the reasons this book assumes

This is a book that, unfortunately, does not undersell itself. Let’s start with the title. It seems categorical: ‘the link’ that uncovers our earliest ancestor. Anyone with the slightest knowledge of evolutionary biology will know that it makes no sense to speak of ‘the link’. It is, at most, ‘a link’. Equally, it makes no sense to talk of our earliest ancestor. That could be anything from the earliest recorded human in a lineage to a mould of slime that may have existed millions of years ago. But we are not dealing with doubt and ambiguity here. We are outside the realm of science, we are in Matrix territory.

Let’s backtrack to 20 May 2009, when this ‘link’, a fossil named Ida, was unveiled at New York’s American Museum of Natural History. ABC News signed up for exclusive access on its primetime news, The History Channel released a movie titled The Link and 100,000 copies of the book were shipped out only after confidentiality agreements were signed. The title is in keeping with the hype. In the same way the hype took attention away from an important fossil discovery, the title does disservice to what is a competent account of the evolution of anthropoids, the category of primates to which we, as mammals, belong.

If you will, the book is a search for our grandparents, the point where anthropoids emerged among primates. The story begins with the Eocene era some 56 million years ago. Already, the dinosaurs had been wiped out by an asteroid collision some eight million years earlier. After the subsequent cooling, the earth had warmed up again and temperatures were what we are likely to face if global warming becomes a reality. During this era, some 47 million years ago, a primate less than two feet tall and not even a year old walked up to the edge of a vast lake that periodically released methane. Gassed to death, it sank to the organic waste at the bottom. The waste eventually became shale, preserving the body in immaculate shape.

This fossil reveals a telling moment in the evolution of anthropoids. It seems to possess characteristics in between those of earlier primates and later anthropoids, as close as we may ever get to a grandparent in the long history of evolution. It was eventually discovered in Germany in 1983, after which it lay in the drawer of a private dealer and was finally uncovered by Jorn H Hurum of the University of Oslo in 2007. Realising its importance—the most complete fossil primate ever found, including skeleton, soft body outline and contents of the digestive tract—he set up a team of leading scientists to study it.

This book sets out to document their work. Hurum named the fossil Ida, after his daughter. We know the primate was a female, because the fossil lacks a bone called baculum. The penis in all primates, except one, is reinforced by this bone and its absence in humans is an interesting aside in the book.

Tudge tells his story well, marshalling the paleontological evidence in a way that would interest a non-specialist. Of course, the book does not live up to the promise on the cover. No book could. But if you are interested in part of the story of how we became human, this should be on your reading list.

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