I’ve managed to cross another one of the list of books I’ve had for ages but never read, in the form of biochemist Nick Lane‘s The Vital Question I bought this book several years ago and have no idea why I took so long to get around to it. Given how quickly things are moving in the biosciences these days, it may even be a bit out of date now, but as far as I’m concerned it’s better late than never.
I haven’t studied biology since O-level (1979) but did chemistry as one of four subjects in the first year year of Natural Sciences at Cambridge and I remember some organic chemistry. I wish I had done Biology of Cells then, though, not because I would have carried on with it but because it’s much more interesting than the subject I did take, Crystalline Materials. Probably much of what I would have learnt in 1982-3 is out of date now.
The Vital Question doesn’t ask a single big question but tackles a number of interrelated questions that together comprise a big mystery in the origin of life, basically the apparently sudden appearance of eukaryotic life (i.e. organisms with complex cells, including plants and animals) as distinct from simpler the forms, archaea and bacteria. Among the fascinating issues are how eukaryotes evolved, why there is no missing link, and why eukaryotic cells are all built on a similar model, what made reproductive sex the way it is, and why in the midst of life there has to be death.
One of the great advances in biosciences since the time I didn’t study it is a revolution in the understanding and practical application of genetics, especially through fast DNA sequencing, not only in biology but also in other fields such as medicine, archaeology and forensic science. One of the valuable points that Lane makes is that the success of genetics led to an emphasis on the role of information – because that’s what genes represent – to the detriment of other essential factors in living cells, especially energy. The book points to the relationship, familiar to physicists, that information relates to entropy, but makes it clear that entropy on its own is not sufficient to understand the thermodynamics of, e.g., respiration and reproduction.
This is a recurrent theme in the history of science, actually, that the success of one particular way of looking at phenomenon often seems to convince people that it provides the complete picture, when some subsequent study demonstrates that usually turns out not to be the case. None of this is to argue that genes are unimportant. They undoubtedly are, but so are other factors including reaction kinetics and environment.
Anyway, to address this big question, Lane gives us a tour of the processes involved at a significant level of complexity but the book is so well-written that it’s actually a bit of a page-turner. As I explained at the beginning I haven’t studies any biology for over 40 years so I struggled at first with some of the technical words, but there is a full glossary to help. The rather dreary pictures are less helpful, but altogether is a superb introduction.
One of the aspects of this book I enjoyed greatly is the number of digressions. That might put some people off, but I thought it helped to paint a true picture of the richness of life in all its forms as well the constraints imposed on it. I didn’t know for example that while most mammals (including humans) have X or Y chromosomes, birds are different: they have W and Z (note to physicists: not to be confused with the gauge bosons). Moreover, while the reproductive sex usually indicated by XX is female (homomorphic) and XY is male (heteromorphic), the opposite is true for birds and some reptiles: females are heteromorphic (ZW) and males are homomorphic (ZZ). Why this difference arose I have no idea, but Lane makes some interesting observations about how it may be behind how some male birds develop exaggerated pigmentation and plumage.
Another question that struck me reading this book is why the human genome is so small. Or rather, why so many other genomes are much bigger. For reasons I described in a post a few years ago, I actually have a CD with my own genome on it. Come to think of it, I no longer have a CD drive so have no way of reading it. Anyway, the human comprises about 3 billion base pairs. Some apparently much simpler organisms have genomes much larger than that. We humans are much simpler than we tend to think! Why is that?
Obviously it has been my turn to digress…
I thoroughly recommend this book for a number of reasons, including the excellent explanations of biochemical processes and the fact that it’s written with such obvious enthusiasm and desire to communicated. Above all, though, Lane does what a scientist should do, i.e. he’s honest about the huge gaps in our knowledge. He doesn’t pretend to answer all the questions he asks, but demonstrates the importance of tackling the big issues head on and acknowledging what is known, what is unknown, and what is speculation. That’s a lesson for all science communicators!
