Writing before the impact of human behavior on the climate was understood, Darwin seems nonetheless to have anticipated its stark reality. He could not have known about the mass extinctions of the twenty-first century, but he would have been unsurprised-if also horrified-by the May 2019 UN report predicting that one million species will go extinct within the next decades. In this and scores of other similarly haunting passages, Darwin depicts the future as a closed door to most of Earth’s inhabitants. And of the species now living very few will transmit progeny of any kind to a far distant futurity for the manner in which all organic beings are grouped, show that the greater number of species in each genus, and all species in many genera, have left no descendants, but have become utterly extinct. Judging from the past, we may safely infer that not one living species will transmit its unaltered likeness to a distant futurity. Darwin returns to it, with great eloquence, in the penultimate paragraph of On the Origin of Species: It is integral to the workings of any ecosystem, indeed the only thing we can count on. That tangled fate is clearly at play in a section of Chapter 4 titled “Extinction Caused by Natural Selection.” Here Darwin says: “as new forms are produced, unless we admit that specific forms can go on indefinitely increasing in number, many old forms must become extinct.” 1Įxtinction is a correlated development, the system-wide housekeeping done by a planet with finite resources. Darwin insists there can be no survivals without a matching number of extinctions, a volatile endgame making evolution not the self-evident triumph of those destined to come out on top, but endlessly fluctuating, with winners and losers continually recalibrated, their fates tangled up to the end.
It does not seem to be an autonomous process, and it is never without its ugly twin. Survival is chancy, circuitous, the effect of complex adaptation, and by no means guaranteed. Complications arise right away, for evolution does not seem to be a straight path for anyone, not even those who win out. It is a ringing tautology, but there would have been no need for Origin if things were that simple. Those who are the fittest-most equipped to survive-survive. Featuring sure winners chasing superlatives, there is no surprise in its outcome. In the fifth (1869) edition of On the Origin of Species, Darwin added a subtitle, “The Survival of the Fittest,” to his pivotal Chapter 4, “Natural Selection.” Taken from Herbert Spencer’s Principles of Biology (1864), this muscular phrase gives the impression that evolution is also a muscular reflex, a straight path from effortless strength to effortless victory.
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