Book Review: The Runes of Evolution
/The Runes of Evolution:How the Universe Became Self-Awareby Simon Conway MorrisTempleton Press, 2015The new book from Simon Conway Morris, The Runes of Evolution, is a vast thing (a bit deceptively so, since Templeton Press has somewhat cannily opted, wonderfully, to print the text in double columns), six hundred pages long with three hundred pages of close-typed End Notes, and it's a testament to the brilliance of the author that such lengths quickly become inviting rather than forbidding. Both at the University of Cambridge and on television shows and lecture circuits, Morris has had a career of teaching the complexities of science, and in many ways The Runes of Evolution is his masterpiece, perfectly capturing the seemingly easy way Morris mixes mind-boggling scientific range with friendly, accessible prose.The book's subject is one that has preoccupied the author for a long time but which tends to get only glancing references in other works on evolution: convergence, the phenomenon observed countless times in nature where specific body forms or other adaptations (everything from specialized noses to infrared light detection) are arrived at independently by the forces of environmental pressure and natural selection at unconnected times in unconnected species: fish and oceangoing mammals streamlining in many of the same ways, for instance, or echolocation being developed by many species, or the most spectacular example, flight itself, which has been independently achieved four different times in the history of life on Earth, although often through the same means:
In the case of birds, the path to the skies is clearer [than that of the Pterosaurs], but at first sight the convergences between at least the birds and the bats might seem to be superficial. Both flap their wings, and that is the end of the story? Not quite, when it comes to digestive physiology they show some intriguing similarities. The intense metabolic demands for flight are evidently also linked to a striking decrease in the size of the genome. This not only occurred independently in the birds and bats, but tellingly also in the extinct pterosaurs.
“The prospect of a more general theory of biology will depend on teasing out what unites form rather than divides it,” Morris writes (noting, winningly, that “In the history of life, things not only change but they get decidedly more interesting”), and although The Runes of Evolution ranges into every detail of living things, one of the main unifying themes in these pages is the convergent evolution of minds, of higher cognition, which is always a dire gamble in evolutionary terms, since big brains take longer to grow than small brains and tend to gobble up enormous amounts of metabolic energy while being far less obviously useful than, say, bristling muscles or sharp fangs. Morris seems interested in all instances of convergence in the natural world, but the convergent development of intelligence seems to fascinate him particularly – even though (or because?) it leads mankind, in his view, into isolated territories. The pathway may be familiar:
It verges on parody to suppose that the story of vertebrate brain evolution is how a nubbin of a brain in a primitive fish, who only had trilobites to talk to, had successive layers of neural tissue plastered on top of it, ultimately to provide the crowning glory of the human neocortex. Not that anybody disputes that there has been striking elaboration, but this beguiling story of slow but relentless evolutionary improvement misses a deeper point.
But the deeper point, to which he recurs again and again, is that “although cognitive worlds are bubbling all around us, only we actually know.” This appears to be the somewhat self-aggrandizing gist of his book's subtitle “How the Universe Became Self-Aware”: that so far as is known, the universe – with all its abundant forces of evolution – has only evolved the particular theorizing, self-regarding capacities of the human brain once. Other species, he grants (thankfully – in the 21st century, far too many such books don't even make such a minimal concession), have developed formidable intelligence, but they haven't gone that one extra step:
For Darwin the mystery of mysteries was the origin of species, but for us it is the nature of mind. Convergence helps us to stake out the territory. Giant brains and cognitive sophistication have evolved multiple times. Obvious manifestations are learned vocalizations, toolmaking, and social play. Less tangibly, sleep, mirror self-recognition, and even an awareness of death are as much tantalizing as informative. All are patently a product of evolution, and the differences that separate us from apes, crows, dolphins, and maybe even octopus are paper thin. This is what Darwin taught, but now we stand alone.
The fallacy underlying all this will be well-known to logicians (who'll use it anyway because at the end of the day they're still human – most of them, anyway), but at least this tendency to equate the hyper-speciality of humanity with the longed-for end goal of all species is always under blankets of control in Morris' book; this is much more a free-wheeling inquiry into the nature of evolution's tool kit than it is a triumphalist narrative of the homo sapiens brain as it Byronically contemplates the universe. And along the way, Morris is never far from a nerdy witticism or cheerful phrase (as when he protests against the usual characterization of sharks as “archaic hoodlums,” or when he writes a line at which all gardeners will smile: “As will be familiar from a garden snail or slug locomotion is achieved by a muscular foot lubricated by mucus, most obvious from the shiny trail as the brute heads toward the lettuces”). The skill our author has developed in a career of intelligently explaining things is evident on every page of The Runes of Evolution, and the book brims with as many questions as answers. The fact that only humans will read it – or care to – is just a hard compromise it needs to make with reality.