万物简史 第525期:丰富多彩的生命(21)（在线收听） |
Goodness knows what the results would be if anyone attempted a similar exercise with the planet's estimated 20,000 types of lichens, 50,000 species of mollusk, or 400,000-plus beetles. 要是有人试图对这颗行星上的大约2万种地衣、5万多种软体动物或40万种以上甲虫做类似的工作，天知道会有什么结果。 What is certain is that there is a great deal of life out there, 有一点是肯定的，世界上存在着大量生命，
though the actual quantities are necessarily estimates based on extrapolations — sometimes exceedingly expansive extrapolations. 虽然实际数量只能根据推断——有时候是漫无边际的推断——来进行估计。
In a well-known exercise in the 1980s, Terry Erwin of the Smithsonian Institution saturated a stand of nineteen rain forest trees in Panama with an insecticide fog, 20世纪80年代，在一次著名的实验当中，史密森学会的特里·欧文在巴拿马雨林里用杀虫剂喷洒了19棵树，
then collected everything that fell into his nets from the canopy. 然后捡起从树上掉进他网里的一切东西。
Among his haul (actually hauls, since he repeated the experiment seasonally to make sure he caught migrant species) were 1,200 types of beetle. 在他的捕获品当中（实际上是几次捕获品，因为他按季节重复了这个实验，以确保逮住迁移的物种），有l200种甲虫。
Based on the distribution of beetles elsewhere, the number of other tree species in the forest, 根据别处甲虫的分布情况、森林里别的树生物种的数量、
the number of forests in the world, the number of other insect types, and so on up a long chain of variables, 世界上森林的数量、别的昆虫的种数等等变量，
he estimated a figure of 30 million species of insects for the entire planet — a figure he later said was too conservative. 他估计整个地球上有3000万种昆虫——他后来说，这个数字还很保守。
Others using the same or similar data have come up with figures of 13 million, 80 million, or 100 million insect types, 别人利用同样的或类似的数据得出的昆虫数量是1300万种、8000万种或l亿种。
underlining the conclusion that however carefully arrived at, such figures inevitably owe at least as much to supposition as to science. 这清楚地说明，得出一个结论无论多么仔细，这样的数字少说也是推测和科学平分秋色。这是必然的。
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