Why should we care? If you’ve seen one look-alike bat, or rat, or parasitic wasp, haven’t you seen them all? In fact, our own lives sometimes depend on recognizing the subtle differences. For instance, South American night monkeys of the genus Aotus used to be regarded as a single species. Then a primatologist found that they really belong to nine separate species that differ in their susceptibility to malaria. That mattered because scientists relied on Aotus as a laboratory animal for malaria studies—and did not realize they could be getting bogus results, and putting human lives in peril, by inadvertently testing malaria treatments on a species that might not be vulnerable to the disease in the first place.
But what really drives scientists to the far ends of the earth in search of new species is something far less pragmatic. Visiting New Caledonia as a young man, the evolutionist and ant taxonomist E. O. Wilson realized that “not just the ants but everything I saw, every species of plant and animal, was new to me.” Years later, the memory made him confess: “I am a neophile, an inordinate lover of the new, of diversity for its own sake.” His greatest desire was to live in a place “teeming with new life forms,” wrote Wilson, now 81. All he wanted was “not years but centuries of time” to take its measure.
Richard Conniff’s The Species Seekers will be out this fall.