Actually, as a test case, wasps are not very taxing. Although they serve to swell the catalogue of Daily Mail bogies, along with soccer hooligans and Germans, they really don't do us a lot of harm. To be sure, they sting people and sometimes people die because they are allergic, and that is immensely sad. But the "fault" in such cases (if "fault" is an appropriate concept) lies not with the creature but with the human immune system. Like all our biological attributes, our immune system has evolved by natural selection; and evolution by natural selection achieves wonderful results but it does not work to human specification and carries no guarantees. Our immune system does a brilliant job in beating off infection (without it we are merely meat and could rot in one hot fortnight) but sometimes it over-reacts: to pollen, to soap powder, to nylon, to nettles, and occasionally to insect stings. It is a pity, but that's life.
What matters is whether wasps sting people gratuitously; out of malice, or for the fun of it. If they did, we would have a right to take a hard line on them. Well, sometimes it may look that way: "We were just sitting in the garden but we all got stung" as Wendy Cramer of Twickenham told the Sunday Telegraph in August 1995. In such a case (if the good family Cramer really were sitting around as peaceably as they say) we have simply to concede that the behaviour of wasps - like our own immune systems - has evolved, and that evolution does not guarantee perfection.
But again, on the whole, natural selection has done a good job. It has in general geared the aggressiveness of all wild creatures precisely to the level it needs to be. For although we may care to demonise whatever stings and bites - hornets, snakes, sharks, tigers, wolves, spiders - no creature could survive in the world if it were gratuitously vicious. To be sure, cats may play with mice and killer whales with sealions, apparently for no better reason than to hone their reflexes. But unless there is a hopeless mismatch (cats against mice, spiders against bean-flies) then attack involves risk, and natural selection is bound to punish any creature that takes unnecessary risks. A creature that takes more risk than is really required will, in the end, miss out to one with finer judgement.
So it would be most unlikely, indeed impossible, to imagine except through mistake that any wild creature, wasp or otherwise, would attack any other creature unless the attack was necessary for its own survival or that of its kin. The only animals that do take what may seem to be outlandish risks are males in pursuit of mates (when often there is no alternative to high risk, and the risk is justified by high reward) and domestic creatures that are bred or trained to be hyper-aggressive, like fighting dogs. But fighting dogs really are an aberration - the product not of natural but of artificial selection, in effect bred to be insane. As the French Lord Rambure commented before Agincourt (Henry V, III, vi): "That island of England breeds very valiant creatures; their mastiffs are of unmatchable courage". Yet, as the Duke of Orleans pointed out, those "valiant creatures" are just "Foolish curs, that run winking into the mouth of a Russian bear, and have their heads crushed like rotten apples!" Natural selection could not have produced creatures as daft as that, whether dogs or wasps.
Wasps do not eat people, and neither do they see us as impediments to marriage. So when they strike, it is because they are provoked, as in: "A family's country ramble turned to horror when a little girl fell head first into a wasp's nest" (Daily Mail, 11 August 1994). Not at all pleasant from the human point of view; but not from the wasps' either.
The standard advice when wasps come by is to ignore them; and at least 99.9 per cent of the time, it works very well. Dammit, I would sting you, or at least poke you sharply with whatever was to hand, if you waved your arms and shouted the way people do at wasps. I do take my own advice on this. Last year wasps nested in the Virginia creeper over the front door. On the hottest days they deployed themselves prettily, though with only desultory defensiveness, like the Household Cavalry. Did we panic, like conscientious readers of the Daily Mail? We did not. I and my family merely spoke to them Prince Charlesishly, and they treated us with the disdain that such naffish behaviour deserves. Natural selection worked in this case, as it usually does: no threat, no response. Live and let live. This year the offspring of that nest have built their papery barracks elsewhere, and good luck to them.
But if wasps have potential to do us serious harm and they render us no indispensable good, does it not make sense to do them in? Well, it depends what is meant by "sense". Human beings might occupy this planet for at least another million years and on balance it seems a good idea to try to do so in the company of other creatures. To do this, we have actively to conserve them: we have messed up the world far too much simply to leave what is left to its own devices. We do have to be a little pragmatic: it was surely a good idea to eliminate the smallpox virus. But arguments based purely on pragmatism are very fragile.
Thus "environmentalists" who seek to impress governments that conservation is worthwhile, and the occasional governments that seek to persuade taxpayers to put their money behind it, commonly resort these days to the notion that other creatures are a "resource", generally preceded by the epithet "vital". Thus, we are told, wildebeest attract tourists, Madagascar periwinkles provide drugs to treat cancer (and what other medicinal goodies might lurk out there?), and mangroves provide nurseries for commercial fish.
We are also told, for good measure, that biodiversity leads to ecological stability, and that species-impoverished ecosystems are liable to collapse. Unfortunately the answer to both lines of argument is the one that met those of Lord Copper: "Up to a point".
Thus, wildlife reserves that are protected only by economic arguments must logically fail when challenged by more profitable enterprise. Wilderness may indeed attract foreign currency - but what happens when some prospector finds oil or gold, which attracts even more? Wild plants do provide drugs, but in general the cheapest and surest route to chemical novelty is in the laboratory. Mangroves may shelter fish but mangroves grow on tropical coasts which generate far more cash when turned into marinas, especially when you add a casino. By contrast, for people, mangroves are among the most hostile environments on Earth.
As for the stability argument, the best we can say is "not proven" or at least, "not simple". Tropical forest, with millions of species, is famously prone to collapse while the cedar and sequoia forests of North America look set for 10,000 years although there is only one species of tree per county. No; in the end, the only argument for conservation that is truly robust is the one that makes the totally arbitrary statement that other creatures matter. Why? Because they do.
And that, in the end, is why we need wasps. They sting people, they do not do much for us, but it is a privilege to share the planet with them none the less. If we cannot see that, then nothing is safe.
Colin Tudge's latest book, 'The Day Before Yesterday', will shortly be available in paperback from Pimlico.
What do you think?
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