The central question of this fascinating book is the precise role of energy in the living world.
Biology is in an interesting state of flux, with some visionary scientists believing that all biological processes are explainable by the laws of physics and mathematics. Meanwhile another group believes that quantum mechanics provides the best explanation for life process and a minority who think that we need to look elsewhere for an explanation of biological organization and function. In the middle is a very large group of teachers are researchers who are unfamiliar with the debates that are raging at scientific conferences and in the scholarly journals.
This is far from being an idle discussion: it has enormous implications for our understanding not only of biology, but also of health and disease. Wherever your sympathies lie in this ongoing debate, it is useful and important to know the current state of play in each of these different camps.
This book is an extremely well written and enthralling account of scientific discovery, that focuses on the efforts of a determined band of investigators who believe that they can - simply by using the currently known laws of physics and mathematics - build a unified theory of how living organisms function.
The idea that energy might be a unifying concept is not new. One of the first to discuss it was D'Arcy Wentworth Thompson who published a classic book on the topic - On Growth and Form - in 1917. In that book Thompson explored the effects of body size on life. Since larger animals need to expend more energy to do their day-to-day jobs, he began the study of metabolic rate and the way in which it sets the tempo for life processes. If metabolism slows, then so do all the processes in cells and organs. There is an almost linear relationship between metabolic rate and animal size: unicellular organs produce and require little energy; a leopard or elephant requires an enormous amount. That much is obvious. But what is less obvious is that there is a precise mathematical formula, first discovered in the 1930s, that relates body mass and energy use.
This initial observation has been expanded over the years and some theorists now consider that metabolic energy is the common denominator in determining animal form and biodiversity.
For example, larger animal species require more food and land, and are therefore more vulnerable to extinction than smaller creatures. An argument that has been applied to the extinction of the dinosaurs and the eventual emergence of small, mobile proto-mammalian species. I was interested to learn that some biologists working in animal conservation have discovered a mathematical law linking the specific area within a region and the number of species that it can sustain. On the other hand, the simple formula linking body mass and metabolic rate is the most parsimonious explanation for the quickest way for an organism to keep its cells supplied with energy, given the way in which the geometry of transportation systems change with size.
Although this a book about biology, it is easy to see that many of the same principles apply in countless other situations, including supply lines for an army, or the provision of men and materials in a game of chess or soccer.
This book explores a number of important idea, though I remain doubtful that all biological phenomena can be explained so neatly. I still tend to favor the group of biologists who think that the ultimate solution to biological form and function requires a new - and a yet poorly defined - organizing principle.
This is science writing at its best, and I highly recommend the book to anyone interested in human and animal biology.