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in principle you ought to be able to go to experts in each area of specialization； ask howmany species there are in their fields； then add the totals。 many people have in fact done so。
the problem is that seldom do any two e up with matching figures。 some sources put thenumber of known types of fungi at 70；000； others at 100；000—nearly half as many again。 youcan find confident assertions that the number of described earthworm species is 4；000 andequally confident assertions that the figure is 12；000。 for insects； the numbers run from750；000 to 950；000 species。 these are； you understand； supposedly the known number ofspecies。 for plants； the monly accepted numbers range from 248；000 to 265；000。 thatmay not seem too vast a discrepancy； but it’s more than twenty times the number of floweringplants in the whole of north america。
putting things in order is not the easiest of tasks。 in the early 1960s； colin groves of theaustralian national university began a systematic survey of the 250…plus known species ofprimate。 oftentimes it turned out that the same species had been described more than once— sometimes several times—without any of the discoverers realizing that they were dealing withan animal that was already known to science。 it took groves four decades to untangleeverything； and that was with a paratively small group of easily distinguished； generallynoncontroversial creatures。 goodness knows what the results would be if anyone attempted asimilar exercise with the planet’s estimated 20；000 types of lichens； 50；000 species ofmollusk； or 400；000…plus beetles。
what is certain is that there is a great deal of life out there； though the actual quantities arenecessarily estimates based on extrapolations—sometimes exceedingly expansiveextrapolations。 in a well…known exercise in the 1980s； terry erwin of the smithsonianinstitution saturated a stand of nineteen rain forest trees in panama with an insecticide fog；then collected everything that fell into his nets from the canopy。 among his haul （actuallyhauls； since he repeated the experiment seasonally to make sure he caught migrant species）were 1；200 types of beetle。 based on the distribution of beetles elsewhere； the number ofother tree species in the forest； the number of forests in the world； the number of other insecttypes； and so on up a long chain of variables； he estimated a figure of 30 million species ofinsects for the entire planet—a figure he later said was too conservative。 others using thesame or similar data have e up with figures of 13 million； 80 million； or 100 millioninsect types； underlining the conclusion that however carefully arrived at； such figuresinevitably owe at least as much to supposition as to science。
according to the wall street journal； the world has “about 10；000 active taxonomists”—not a great number when you consider how much there is to be recorded。 but； the journaladds； because of the cost （about 2；000 per species） and paperwork； only about fifteenthousand new species of all types are logged per year。
“it’s not a biodiversity crisis； it’s a taxonomist crisis！” barks koen maes； belgian…bornhead of invertebrates at the kenyan national museum in nairobi； whom i met briefly on avisit to the country in the autumn of 2002。 there were no specialized taxonomists in thewhole of africa； he told me。 “there was one in the ivory coast； but i think he has retired；” hesaid。 it takes eight to ten years to train a taxonomist； but none are ing along in africa。
“they are the real fossils；” maes added。 he himself was to be let go at the end of the year； hesaid。 after seven years in kenya； his contract was not being renewed。 “no funds；” maesexplained。
writing in the journal nature last year； the british biologist g。 h。 godfray noted that thereis a chronic “lack of prestige and resources” for taxonomists everywhere。 in consequence；“many species are being described poorly in isolated publications； with no attempt to relate anew taxon2to existing species and classifications。” moreover； much of taxonomists’ time istaken up not with describing new species but simply with sorting out old ones。 many；according to godfray； “spend most of their career trying to interpret the work of nineteenth…century systematicists： deconstructing their often inadequate published descriptions orscouring the world’s museums for type material that is often in very poor condition。” godfrayparticularly stresses the absence of attention being paid to the systematizing possibilities ofthe internet。 the fact is that taxonomy by and large is still quaintly wedded to paper。
2the formal word for a zoological category； such as phylum or genus。 the plural is taxa。
in an attempt to haul things into the modern age； in 2001 kevin kelly； cofounder of wiredmagazine； launched an enterprise called the all species foundation with the aim of findingevery living organism and recording it on a database。 the cost of such an exercise has beenestimated at anywhere from 2 billion to as much as 50 billion。 as of the spring of 2002； thefoundation had just 1。2 million in funds and four full…time employees。 if； as the numberssuggest； we have perhaps 100 million species of insects yet to find； and if our rates ofdiscovery continue at the present pace； we should have a definitive total for insects in a littleover fifteen thousand years。 the rest of the animal kingdom may take a little longer。
so why do we know as little as we do？ there are nearly as many reasons as there areanimals left to count； but here are a few of the principal causes：
most living things are small and easily overlooked。in practical terms； this is not always abad thing。 you might not slumber quite so contentedly if you were aware that your mattress ishome to perhaps two million microscopic mites； which e out in the wee hours to sup onyour sebaceous oils and feast on all those lovely； crunchy flakes of skin that you shed as youdoze and toss。 your pillow alone may be home to forty thousand of them。 （to them your headis just one large oily bon…bon。） and don’t think a clean pillowcase will make a difference。 tosomething on the scale of bed mites； the weave of the tightest human fabric looks li