I wish I had been more attentive to an item I glimpsed on television some weeks ago. Its general drift, as I recall, was that an environmental scientist had been richly rewarded by the results of a super-scrupulous scan of a very tiny area. Instead of studying the ecology of (say) a mountain range, or a peninsula, he crept on hands and knees over a single paddock, magnifying-glass in hand like a caricature of Sherlock Holmes. (It was something like that.) This intensive scrutiny identified two species up till now unknown to science, several creatures not thought to occur within…