Human beings have turned wolves and buffaloes into tame dogs and cows, but in the tiny mosquito we have met our match.



Malaria, spread by mosquitoes, has killed half the members of our species who ever lived. And then there are dengue fever, yellow fever, encephalitis, elephantiasis and dozens of other mosquito-borne viruses named after places from the West Nile in Africa to Australia's Ross River.



When it is not lethal - the mosquito has not yet transmitted disease to a single human in New Zealand - it is still, at the very least, a nuisance.



Indeed, our local exemption from mosquito-borne disease may be temporary, a quirk due to our own late arrival here.

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New Zealand had only 12 native species of mosquito before humans turned up. Japan has 67, England 32.



Four more species have arrived as stowaways in the past 160 years. All four can transmit diseases to humans, and researcher Jose Derraik said it was only a matter of time before they did so here.



Yet remarkably, only female mosquitoes bite, and only a few of those live long enough to bite a second time and so potentially carry disease from their first victim to their second.



Despite the fear they strike in us, the life of the average mosquito is dangerous and short. They lay their eggs as batches of 200 or more, tied together in a miniature boat the size of half a grain of rice.



Each egg hatches to produce a tiny larva with a long, worm-like body that hangs head-down in the water, using its "whiskers" to drag microscopic food into its mouth. After 12 days, the larva splits to reveal the pupa, which has taken shape inside it.



Andrew Spielman and Michael D'Antonio in their book Mosquito describe the pupa as "comma-shaped". A worm-like body curves downwards in the water, but the head, now on top, is swollen into an enormous bubble from which, two days later, the mosquito emerges.



After this brief gestation, the creature misses out completely on childhood and adolescence and plunges almost immediately into mating.



In most species, newborn females at least get a few hours' rest before sex begins. But, write the Americans Spielman and D'Antonio, "a shocking exception to this rule is an exotic mosquito in New Zealand called Opifex fuscus, which develops in pools of salt water along the coast.



"Rapacious males stake out the watery places where mosquito pupae are present," they write.



"As the pupae begin to open, the males will skim across the water like submarine-hunting aircraft. When a pupa rises to break the surface of the water, the male races to the spot.



"He seizes the pupa, and the force of his attack can cause it to split open. The mosquito inside is helpless, because his or her legs have not yet freed themselves.



"If the emergent mosquito is a male, the marauder lets go. If it is a female, an event that is essentially a rape ensues, with the male assuring that the female is impregnated in its first moment of adult life."



The female needs just one more ingredient to nourish her eggs: blood.



Instinctively, she is drawn, first by scent and then by vision, to the nearest flesh.



First she probes for the right place. Then she sinks her long proboscis into the victim's skin and sucks. In 90 seconds she sucks up two to three times her own weight. She must then rest to digest it.



An hour or so later, she is finally ready to lay her eggs and start the cycle again.



Avoiding mosquitoes


* Cover up with long sleeves and trousers.


* Don't linger near stagnant water.


* Don't let stagnant water collect in old cans, gutters, drains or puddles around the house.


* Use mosquito repellents.