Natural Straw Man

There was a just down-right bizarre op/ed in Sunday’s New York Times . Here’s the penultimate paragraph:

Unfortunately, humans seem to forget this fact when we find ourselves turning to nature to guide us through difficult choices, such as arguments about whether life begins at conception, or over the proper structure of the family. Or, more recently, regarding the morality of cloning. Whether we’re talking about raising bigger cattle or growing life-saving organs or trying to “live forever,” both sides like to stress their abilities to judge what is “natural.” Judging from Komodo dragons, lizards and sharks, the answer seems to be that for reproduction, almost anything goes.

Who, exactly, makes the type of argument coming in for criticism here? I don’t know any natural law thinker who does anything remotely similar to this. Caricaturing natural law arguments, of course, is always easier than wrestling with the real thing.