Nature does nothing in vain
Man alone among living things knows that he has evolved. Man alone is able to decide what direction or directions he desires his own future evolution to follow, and can set about acquiring the knowledge he needs to achieve the desired results.
–Thomas Goudge, Ascent of Life
According to recent scientific findings, we are responsible for the elimination of three species every hour, a rate approaching that holocaust of species associated with the age of dinosaurs.1 Secretary General of the United Nations Ban Ki Moon recently declared that “the global response to these challenges [of biodiversity] needs to move much more rapidly.”2 But even if we could significantly reduce gas emissions and put a halt to global warming, biodiversity is likely to continue declining. It takes on average a million years for a species to branch off and distinguish itself; no new phyla have surfaced for over one hundred million years. Our phenomenological experience of biodiversity is thus almost exclusively one of decreasing numbers. Where Darwin once saw an entangled riverbank teeming with life, our vision of the earth’s future landscape is as desolate as the moon.
But perhaps such worries are unwarranted? Insofar as evolutionary theory commits us to some degree of interspecific competition, it seems counterproductive to preserve and prolong the life of each and every species. Who is to say that two million species is not preferable to twenty? Moreover, why not strive to preserve variation within a specific species, especially given that the taxonomic units themselves are so contested? Since subspecies are potential species, perhaps our attention is better placed there.
Numbers aside, there are many arguments in favor of preserving, if not enhancing, biodiversity. Some are consequentialist, appealing to values instrumental to the welfare of Homo sapiens, such as the medical potential of tropical plants. Other arguments are deontic, appealing to intrinsic values, such as the beauty of the wilderness or the sanctity of life. None are entirely persuasive, however, for the simple reason that they assume we can, in some meaningful sense, alter the pace of the evolutionary process and thus ensure greater longevity either for humans or for other species. Implicit in these arguments is the belief that we can step outside of a realm called ‘Nature’: that human agency can be partitioned and treated as a separate sphere that does not follow the same deterministic chains found in the biological realm.
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