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No. 43: Jan-Feb 1986

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The Biological Diversity Crisis

If life fills all available energy niches, life must be capable of transforming itself (or of being transformed) into a multitude of different energy transducers or energy utilizers. E.O. Wilson has outlined the diversity of terrestrial life in a recent issue of BioScience. The earth, it appears, is a veritable Gene sis Machine; and it is only one planet among a possible infinitude.

So many terrestrial species have already been described that one could easily believe that biological collectors roaming the planet's wild places have just about completed their task. Some recent totals: 47,000 species of vertebrates, 440,000 plants, and 751,000 insects. But we may not even be close to grasping life's diversity on earth! We do well in counting the large mammals and birds, but most insects and microscopic forms of life have escaped description. To illustrate, in 1964, the British ecologist C.B. Williams, combining intensive local sampling and mathematical extrapolation, extimated the insect population as 3 million species. However, by 1985, this figure has been raised ten-fold to 30 million species.

Why the huge jump? For the first time, entomologists had found a way to efficiently sample the canopies of tropical forests. This rich stratum between the sunlight and gloomy forest floor 100+ feet below had been largely neglected before. The slick tree trunks and the attacking swarms of wasps and stinging ants deterred the insect counters. What the collectors did was to fire projectiles with ropes over the high branches and then haul up canisters of a knockdown gas. Insects rained down -- a cloudburst of new species -- neatly collected on sheets spread out below. Such techniques led to the 30-million figure. As Wilson put it, "The pool of diversity is a challenge to basic science and a vast reservoir of genetic information."

(Wilson, Edward O.; "The Biological Diversity Crisis," BioScience, 35:700, 1985.)

Comment. Are there other "hot spots of diversity" waiting to be discovered? Probably, but they will be under our feet, in the deepest waters -- places we do not frequent or suspect. We do know of an ancient mudbank that gave birth to multitudes of new and fantastic creatures. See below.

From Science Frontiers #43, JAN-FEB 1986. 1986-2000 William R. Corliss