This was an extremely interesting book, although I can’t say that it was an easy read for me; I think I was coming to it about 55 years too late. I struggled with the scientific language, although I appreciate that the author did a great job of making the concepts of evolutionary biology as accessible as possible for the lay reader. His style was engaging and at times amusing, and I appreciated the personal touches about his own research. This gave an insight into the controversies and academic disagreements that added a human touch to the book, especially around the chapter ‘The Diet of Worms’, where the author describes ‘the story of…the acoelomorphs and Xenoturbella…where I will indulge myself by talking about these and some lesser-known worms that have been my passion for more than thirty years.’
I doubt I will be able to retain much of the scientific information, but there is also a good deal of interesting history of the development of the study of evolution and the impact of genetics. The most impressive aspect I do take from this read is timescales; when you come to a chapter entitled ‘The first three billion years’ it does take the breath away, especially when compared to the traditional estimate of human lifespan as three score years and ten. Then there are the aspects of scale in the size of the organisms being researched, and our ability to examine microscopic forms of life. And again, on the question of the number of species in existence today:-
‘Conservatively…at least 8 million species alive today are unknown to us - the great majority in fact.’
Finally I suppose what made the most impact for me was the philosophical aspect of evolution: from page 203 of the hardback edition:-
‘The humbling reality is that evolution has no aim; the evolution of humans had no inevitability at all, and our path up the tree could have been snuffed out on a billion different occasions…on the vast scale of the tree of life, our species is a single leaf, a very recent arrival, and one that may not be around for long.’ Hence Shelley in ‘Ozymandias’
“ ‘Look on my Works, ye Mighty, and despair !’
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare
The lone and level sands stretch far away.”
And finally, from the last chapter ‘Unknown Unknowns and the end of the affair’ - ‘We can make one safe prediction, however: the only real certainty for the future of the tree of life on earth is that it will one day stop growing.’ But after all, what a tree it is!