
Max Telford (John Murray (UK)
Most of us can imagine a tree of life; some can even sketch one out. Branches coming off branches coming off branches, each describing a turn in evolutionary history. Over here are the molluscs. Over there, the apes. Look closer in that general area and you might even find us, Homo sapiens.
But do any of us truly marvel at this giant tree, as we should? As zoologist Max Telford’s The Tree of Life: Solving science’s greatest puzzle makes clear, it is a wondrous thing. We can follow its branches backwards in time to reveal the characteristics of animals for which there is no fossil record. It can even take us to the starting point of current life, known as LUCA, the last universal common ancestor.
Advertisement
The Tree of Life, then, is a millennia-spanning science-history book in the spirit of Thomas Halliday’s blockbusting Otherlands, though it is notably chattier, more prosaic. That’s no bad thing. The tree of life itself is deceptively complicated, so a straightforward guide is a boon.
Telford lays out those complications, one by one. The first swallow of the northern hemisphere spring is easily mistaken for the similar-looking swift. This book will teach you that, in fact, they are as distant “as a hummingbird is to an owl”. Trickily, the two birds developed similar appearances along quite separate branches.
That sort of basic confusion is just the start. What about the characteristics by which organisms should be grouped? Which traits are homologous and which are merely similar? And what does “homologous” mean? Piecing it together is, in Telford’s words, “an unfathomable challenge”.
Thankfully, as Telford explains, modern researchers have ever greater resources – including genetics. Charles Darwin compared wings and bones; we compare proteins, nucleotides and ribosomal RNAs, using such complex science it tests the bounds of Telford’s conversational style. Indeed, the middle stretch of the book sags under the weight of so much hard information.
Still, it all prepares us for a brilliant finale, in which he traces the 4 billion years or so from LUCA to Homo sapiens – and beyond. “The tree of life is only part grown,” he writes, “much more than a sapling but still some way from maturity.” Let us do what we can to tend it.
Peter Hoskin is books and culture editor at Prospect magazine
New Scientist book club
Love reading? Come and join our friendly group of fellow book lovers. Every six weeks, we delve into an exciting new title, with members given free access to extracts from our books, articles from our authors and video interviews.