London underground source of new insect forms London underground source of new insect forms To: Ban-GEF@lists.txinfinet.com, GENTECH@ping.de Subject: London underground source of new insect forms From: MichaelP <papadop@PEAK.ORG> Date: Wed, 26 Aug 1998 06:51:16 -0700 (PDT) Content-Type: TEXT/PLAIN; charset=US-ASCII Resent-Message-ID: <"99waf.A.i_E.NTB51"@data.free.de> Resent-Sender: gentech-request@data.free.de London Times August 26 1998 A NEW species of mosquito is evolving on the London Underground in a development that has astonished scientists. The insects are believed to be the descendants of mosquitoes which colonised the tunnels a hundred years ago when the Tube was being dug. When they went below ground they were bird-biting pests. But over a century, deprived of their normal diet, the mosquitoes have evolved new feeding behaviour, dining on mammals including rats and mice - and human beings. They now plague maintenance workers.

Kate Byne and Richard Nichols of Queen Mary and Westfield College in London have carried out tests to see if the Tube's mosquitoes, which have been named molestus, are now different from Culex pipiens, the bird-biting species which entered the Underground last century. To their amazement they found that it was almost impossible to mate those living above ground with those in the subterranean world, indicating that the genetic differences are now so great that the ones underground are well on their way to becoming a separate species. This usually happens only when species are isolated for thousands rather than tens of years. The team, whose findings are reported in BBC Wildlife magazine today, have also found genetic differences between mosquitoes on different Tube lines. They believe this is due to the draughts dispersing the insects along but not between lines. During the Second World War the insects attacked Londoners sheltering from Hitler's bombs. Roz Kidman Cox, the magazine editor, said: "It's a remarkable story of evolution. The scientists say that the differences between the above and below-ground forms are as great as if the species had been separated for thousands of years." The conditions on the Underground are probably ideal for mosquitoes to breed rapidly and frequently throughout the year.

Temperatures can be balmy and the network is prone to penetration by water creating pools of stagnant water for breeding. There are more than 1,600 varieties of mosquitoes which live from the Arctic tundra to the tropical rain forests. ** NOTICE: In accordance with Title 17 U.S.C. Section 107, this material is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes. ** BBC News | Europe | New London underground mosquitoes emerge Wednesday, August 26, 1998 Published at 07:45 GMT 08:45 UK World: Europe New London underground mosquitoes emerge Scientists believe they have discovered a new breed of mosquito deep in the London underground railway network. The insects appear to have mutated from the bird-biting form that colonised the underground when it was built in the last century to a variety that nips rats, mice and maintenance workers. The scientists say the underground mosquitoes are reluctant to mate with their outdoor cousins, indicating that they have become a separate species -- a process that normally takes thousands of years rather than decades.

From the newsroom of the BBC World Service Humans are 'creating new species' including a tough breed of mosquito | Daily Mail Online comments We are all familiar with how human activities are driving the extinction of species around the world. But although you might not expect it, this is not the only effect our activities have on the animal kingdom. Humans are in fact causing the rapid evolution and making new species of plants and animals emerge, according to a new study. As the common house mosquito adapted to the environment of the underground railway system in London, it established a subterranean population. Now named the 'London Underground mosquito', it can no longer interbreed with its above ground counterpart and is effectively thought to be a new species HOW MANMADE SPECIATION WORKS The process can take place by accident, through the emergence of new ecosystems like urban environments, or through the domestication of animals and crops. Unnatural selection caused by hunting can lead to new traits emerging in animals, which can eventually lead to new species. The deliberate or accidental relocation of species can lead to hybridization with other species. The study, led by the University of Copenhagen, outlined many examples of the process of man-made speciation, where human activities lead to the introduction of a new species.

The process can take place by accident, through the emergence of new ecosystems like urban environments, or through the domestication of animals and crops. Unnatural selection caused by hunting can lead to new traits emerging in animals, which can eventually lead to new species. The deliberate or accidental relocation of species can lead to hybridization with other species. This has meant more new plant species in Europe have appeared than are documented to have become extinct. RELATED ARTICLES Share 97 shares Since the last Ice Age, 11.500 years ago, it is estimated that 255 mammals and 523 bird species has gone extinct (like the Dodo, pictured) , often due to human activity. In the same period, humans have relocated almost 900 known species and domesticated more than 470 animals and close to 270 plant species Recent genetic data for the damselfly in Central America suggests forest fragmentation has led it to diverge into more than one species One example of such animals is the 'London Underground Mosquito'. As the common house mosquito adapted to the environment of the underground railway system in London, it established a subterranean population.

The London Underground mosquito can no longer interbreed with its above ground counterpart and is effectively thought to be a new species. But this does not mean our activities are benefitting global diversity as much as they are harming them, the authors said. 'The prospect of "artificially" gaining novel species through human activities is unlikely to elicit the feeling that it can offset losses of "natural" species,' said lead author Dr Joseph Bull. 'Indeed, many people might find the prospect of an artificially biodiverse world just as daunting as an artificially impoverished one.' 'We also see examples of domestication resulting in new species. According to a recent study, at least six of the world's 40 most important agricultural crops are considered entirely new' said Dr Bull. Although it is not possible to quantify exactly how many speciation events have been caused through human activities, the impact is potentially considerable, the study says. 'In this context, "number of species" becomes a deeply unsatisfactory measure of conservation trends, because it does not reflect many important aspects of biodiversity,' said Professor Martine Maron from the University of Queensland. 'Achieving a neutral net outcome for species numbers cannot be considered acceptable if weighing wild fauna against relatively homogenous domesticated species.

'However, considering speciation alongside extinction may well prove important in developing a better understanding of our impact upon global biodiversity. We call for a discussion about what we, as a society, actually want to conserve about nature.' The researchers warn current extinction rates may soon lead to a 6th period of mass extinction. Since the last Ice Age, 11.500 years ago, it is estimated 255 mammals and 523 bird species has gone extinct, often due to human activity. In the same period, humans have relocated almost 900 known species and domesticated more than 470 animals and close to 270 plant species. MAMMALS WERE ALMOST WIPED OUT WITH THE DINOSAURS Over 90 per cent of mammal species were wiped out by the same asteroid that killed the dinosaurs 66 million years ago. A recent study published in the Journal of Evolutionary Biology , showed just four of the 59 species examined survived, meaning 93 per cent became extinct across the Cretaceous-Paleogene boundary.

The scientists analysed the published fossil record from western North America from two million years before the asteroid hit, until 300,000 after the calamitous event. They compared species diversity before and afterwards to estimate the severity of the event and how quickly the mammals recovered. The extinction rates were much higher than previous estimates based on more limited data sets, explaining why the severity of the extinction event was previously underestimated. However, the researchers also discovered mammals recovered more quickly than previously given credit for.

Heredity - Culex pipiens in London Underground tunnels: differentiation between surface and subterranean populations Heredity (1999) 82, 7–15; doi:10.1038/sj.hdy.6884120 Culex pipiens in London Underground tunnels: differentiation between surface and subterranean populations Katharine Byrne 1 , 2 and Richard A Nichols 1 1 Queen Mary and Westfield College, University of London, Mile End Road, London E1 4NS, UK Correspondence: Byrne Katharine, Conservation Genetics Group, Institute of Zoology, Regents Park, London NW1 4RY, UK E-mail: k.byrne@ucl.ac.uk 2Present address: Conservation Genetics Group, Institute of Zoology, Regents Park, London NW1 4RY, UK Revised 5 December 1997; Accepted 3 March 1998. Top of page Abstract Genetic variation was quantified between surface-dwelling populations of Culex pipiens and the so-called molestus form found in the London Underground (the Underground) railway system.

The molestus form is a commercially important biting nuisance and in the southern part of its range is also a disease vector. The surface and subterranean populations were genetically distinct, with no evidence of gene flow between closely adjacent populations of the different forms, whereas there was little differentiation between the different populations of each form. The substantially reduced heterozygosity in the Underground populations and the allelic composition suggest that colonization of the Underground has occurred once or very few times. Breeding experiments show compatibility between the Underground populations but not with those breeding above ground. There is evidence of greater gene flow and a mixing of molestus and pipiens traits in the south of the species range. This paper considers the processes that may allow establishment of reproductive isolation in the north of the species range but not in the south. Keywords: Discussion Levels of genetic differentiation The initial assignment of two population types based on laboratory mating behaviour suggested that there were two distinct groups, which correlated to hypogeous (enclosed) and epigeous (open) breeding sites. The genetic data also show significant support for the division of the London population of C. pipiens into two subgroups, pipiens and molestus, which correspond to the different breeding behaviour in the laboratory.

This result is readily apparent from the ordination of GST values, which clusters the populations into two groups. The separation into two distinct clusters indicates that gene flow between the two is absent or limited. Each subterranean population was paired with a surface population close by, so appreciable gene flow over a few hundred metres would have been sufficient to produce a thorough intermingling of the two categories of population in the ordination. Two observations suggest that even where molestus and pipiens populations are in contact gene flow is limited or, conceivably, absent. First, the Oval population ( , Fig. 1 ), clusters with the surface populations on the criteria of genetic distance and postmating and premating reproductive isolation, despite being underground (although open to the sky). Similarly, a previous study by Chevillon et al. (1995) found that mosquitoes collected from what they termed 'open hypogeous sites' were not differentiated from epigeous populations. Secondly, the Beckton population ( , Fig. 1 ) is clearly flying on the surface to reach its human victims.

Although the breeding sites beneath houses have been blocked, other sites have not yet been located by the pest control authorities; one possibility is the large containers on an adjacent but inaccessible derelict industrial site. The genetic data only give a hint of gene flow: Beckton clearly clusters with the Underground populations, but it does show higher heterozygosity than the Underground populations, which might be a consequence of limited gene exchange with the local surface populations. The Underground populations are much less tightly clustered than those overground, suggesting that gene flow is more limited or genetic drift relatively stronger. The significant genetic differentiation between lines (see Table 4 ) can be explained as a consequence of the shaping of gene flow by the tunnel system. Whereas the lines run through tunnels connected principally at the interchange stations, the piston-like action of trains within a tunnel creates a strong draught that may move the adults between breeding sites on the same line. This picture of isolation contrasts with genetic studies from more southerly populations (France, Spain and Italy), where there is more evidence of extensive gene flow between pipiens and molestus populations.

The penetration of insecticide-resistance genes into hypogeous populations ( Rivet & Pasteur, 1993 ; Chevillon et al., 1995 ) provides the most straightforward case. This transmission of resistance alleles is not necessarily an indication of frequent gene exchange, as the strong selection pressure imposed by insecticide use could have established resistance in the hypogeous populations from a very small number of successful migrants. More straightforward evidence comes from Italy ( Urbanelli et al., 1981 ). Three types of population were found on the basis of genetic surveys of allozyme loci: those consisting solely of C. pipiens pipiens, others consisting solely of C. p. molestus and also populations which were intermediate and were presumed to have arisen by hybridization of the other populations. Reproductive isolation The lack of demonstrable gene flow between the two forms in London may, in part, be explained by the implications of the breeding experiments, in which no offspring were recorded from crosses between Underground and surface populations. The ability to mate in confined spaces (stenogamy) may be a major contribution to premating reproductive isolation.

Intriguingly, the Oval population, which seems to be an essentially overground population living underground (but below open sky) produced one (F1) egg raft. The F2 eggs, however, failed to hatch. The genetic distances measured by the present study between the Underground and surface populations (0.07–0.24) would suggest that the relationship between the two population types is between that of local populations and subspecies (see Ayala, 1975 ). However, genetic distances may not be useful in populations where demographic effects are the dominant factor in the population history; for example, they do not reliably separate domestic livestock breeds (see, e.g. MacHugh et al., 1997 ). Using Nei's formula (see Nei, 1987 ), the estimated time since separation of the surface and Underground populations is 100 000 years, even using the correction for drift in one population. This time-scale is, of course, inconsistent with the known history of the tunnels, most of which are less than 100 years old.

A second illustration of the imprecise nature of such estimates of separation time is provided by the Mogden population, which has only existed as a caged population for 10 years and yet is as distinct as molestus and pipiens. These differences can be explained as a combination of severe genetic drift and the effects of selection in a caged environment. This laboratory history may be analogous to that of populations that adapt to a subterranean life in the wild: they may also be presumed to have experienced strong selection and substantial genetic drift. Origin of the Underground populations Two possible sources were considered for the colonization of the London Underground—local London surface populations and long-distance migrants from Mediterranean populations. Long-distance migrants Populations of C. pipiens from the Mediterranean region, especially those from North Africa, show similarities to molestus populations from Britain. In particular, they have reduced polymorphism and higher frequency of some alleles associated with the Underground populations ( Villani et al., 1986 ). Little evidence has been found to support the proposal that the London Underground was colonized from this source. The alleles found in the Underground do not include any that are otherwise found only outside Britain.

Only Got-1 is fixed for an allele that is rare on the surface but that is frequent in molestus-type individuals from other areas ( Chevillon et al., 1998 ). The identity of alleles was confirmed by cross-checking with control strains provided by M. Raymond. Local colonization The data are more consistent with local populations being the source of molestus populations in the Underground. However, Fig. 1 shows that there is no association between individual Underground populations and local surface populations, which suggests that multiple independent colonizations are unlikely or, at least, that such events are rare. The most parsimonious explanation is a single colonization. This would explain the fixation of a single allele at multiple allele loci such as the esterases. The similarity of the Underground populations to the more distant Beckton population (nearest Underground line 4 km) raises the possibility that adaptation to the underground environment may have occurred only once, and that the established subterranean populations are the source for subsequent colonizations. Adaptation, population fragmentation and reproductive isolation The distinction between pipiens and molestus forms appears to increase with latitude. This pattern can be interpreted in terms of the interplay of deterministic and stochastic processes that can lead to reproductive isolation.

The requirement for a winter diapause at high latitudes may play a pivotal role. In North Africa (below 38°N) the above-ground populations are diapause-incompetent, a pattern that may be related to day length ( Zimmerman et al., 1985 ). At the other extreme of the range, northern European subterranean populations become isolated from the surface populations with the onset of diapause in the surface form in the Autumn. Gene flow is therefore restricted for two reasons. First, there is a shorter period when breeding in the two forms overlaps. Secondly, if subterranean populations set up satellite populations above ground, they will not survive the winter and will only have a limited life during which they could act as stepping-stones for gene exchange. These trends vary in a predictable way from the south to the north of the range. The intervening northern Mediterranean populations show the expected evidence of intermediate gene flow and this would explain the diminished differentiation into molestus and pipiens forms. Two stochastic processes also come into play in the north of the range. Genetic drift will tend to fix molestus traits in subterranean populations.

The consequent linkage disequilibrium with eurygamy above ground and lack of diapause below ground will further hamper gene flow throughout the genome. In addition, the establishment of different clones of the Rickettsia-like bacterium Wolbachia pipientis can provide the coup de grâce to gene flow by leading to incompatibility of matings between differently infected populations. The crossing types are sufficiently labile to change from place to place and through time in the same population ( Raymond et al., 1986 ; Magnin et al., 1987 ). Indeed C. pipiens shows a high number of incompatible cytotypes relative to other insects, despite the unexceptional degree of genetic divergence between their strains of Wolbachia, which may indicate interactions between Wolbachia and Culex genomes ( Guillemaud et al., 1997 ). This combination of factors can explain why gene flow is negligible or absent between the two forms in the populations that were studied. As it appears plausible that colonization of the London Underground has occurred only once, the reproductive isolation could have accumulated in the few hundred generations since then.

Conversely, in the south of the range, where climate promotes more frequent gene flow, this may be sufficient to prevent the establishment of reproductive isolation, even though the pleiotropic effects of selection in the underground environment are the same. BBC - Earth - The unique mosquito that lives in the London Underground The unique mosquito that lives in the London Underground When construction of the London Underground began in the 19th Century, there was an unexpected consequence: evolution By Katie Silver 24 March 2016 Regular riders of the London Underground may bemoan the iconic and occasionally fierce tube mice . But there is another, smaller animal living in the Underground that is perhaps even more at home in the subterranean network – since it actually evolved in the unique conditions of the tube environment. The London Underground mosquito is a genetically distinct subspecies. It was first reported during the Blitz of World War Two, when the Tube's tunnels were used as overnight bomb shelters. Over the course of the war, almost 180,000 people sheltered in the Underground. They were ravaged by all sorts of insects. "The Tube then was a very different place than it is now," says Steven Judd , Head of Environment for the London Underground.

With standing water and different pest controls, flies, ticks, lice and fleas were a lot more common than they are now, he says. After the war, other than the odd complaint of biting made by maintenance workers, the mosquito received scant attention. That was until almost 50 years later when a London-based doctoral student decided to study these subterranean biters. Over the course of the war, almost 180,000 people sheltered in the Underground Katharine Byrne collected mosquitoes from seven sites across the 180km (110 mile) network. She found they were fundamentally different from their surface-dwelling relatives. While the above-ground Culex pipiens bit only birds, the Culex pipiens molestus – named for their tendency to molest – had a taste for human blood. "The Culex is a very common mosquito," says biologist Bruno Gomes from the Liverpool School of Tropical Medicine. "There are hundreds or thousands of types of them and they're not very harmful." While they look the same as Culex pipiens, the molestus mosquitoes behave in a different way.

Aside from being bird-biting, the above-ground midge-like flies hibernate in the winter, need blood to lay their eggs and require a lot of space in which to mate. The new subspecies does not require any of these. "These differences can be interpreted in a straightforward way as adaptations to a subterranean life," wrote Byrne . Since there were no birds to feed on, they began feeding on mammals, mostly rats and humans. They mated in closed areas, because they had to – and they lost their tendency to hibernate in winter because there are no obvious seasons underground. The tunnels were largely sealed off from the surface, and some of the mosquitoes found themselves trapped underground Byrne also found the underground mosquitoes are now so distinct they can no longer interbreed with other mosquitoes. "There are differences in both the mating behaviour and the reproductive biology," says David Reznick , a biologist at the University of California in Riverside. While the surface mosquitoes form big swarms in order to pair off and breed, underground ones are not as abundant so it is just individuals who choose each other to mate. After the London Underground system's construction, the tunnels were largely sealed off from the surface, and some of the mosquitoes found themselves trapped underground.

It was this physical barrier, Byrne wrote, that caused the divergent evolution of the two populations. It was "evolution by natural selection but in a speeded-up form," writes Tom Quinn in his book London's Strangest Tales . It's unclear if it evolved there or was brought into the Underground system With one species breeding above ground and the other below, for some 100 years, the stage was set for a new subspecies to evolve. Scientists say that it might have taken just a few hundred generations to do so. "People usually think of speciation as being very slow and as something you can't see happening," says Reznick. "But in this example, you can sort of see it happening. It's a relatively recent phenomenon and you can see a clear start date" – when construction of the London Underground began in 1863. Not everyone is convinced though. "It's unclear if it evolved there or was brought into the Underground system… from the freight and fruit movement into the docks of London," says Judd. There is not enough research to give us an indication, he adds.

It is also found in metropolitan Tokyo and in the New York subway This might come as a surprise, given that there is actually a diverse array of species available to study in the London Underground network. Mice, foxes and even tortoises have been found below ground, says Judd. They live amongst tunnel fluff, made up of human hair and clothes fibres, and tunnel dust: carbon that comes from the train's brake shoes. "In 2015 we had no customer complaints related to biting incidents, with 1.3 billion passengers travelling on the system," he says. What is clear is that the molestus mosquito is not unique to the London Underground, says Gomes. It is actually found in all sorts of human underground constructions, from water systems to the basements of large houses. It has been found in similar enclosed environments, such as caves and sewers, across Western Europe, particularly temperate countries such as Spain and Portugal. It is also found in metropolitan Tokyo and in the New York subway. Still, Reznick argues there are a number of genetic factors that suggest the underground mosquito first evolved in London.

Mice, foxes and even tortoises have been found below ground For instance, Byrne's research involved sampling 12 surface mosquito populations near Underground sites. She compared the genetic makeup of overground and underground mosquitoes and found their alleles, or gene variants, to be incredibly similar. "If they [the subterranean mosquitoes] had come from Spain, you would expect them to have distinct alleles to those above ground," says Reznick. The underground insects should then have been most closely related to Spain's above-ground mosquitoes. But this was not the case: London's underground and overground mosquitoes are each other's closest relative. What's more, the Underground mosquitoes are all quite genetically similar. "If you have a big population of humans and then 20 go and colonise an island somewhere, the colonisers will only have genes that are a small subset of the initial population," says Reznick. A few hundred years in the right circumstances can form a new species The underground mosquitoes are so similar to each other that it "suggests a small number of genetic individuals created this population", he says. Reznick says finding the molestus mosquito in other countries only further demonstrates how incredible the process of speciation is.

It "shows that the capacity of surface mosquitoes to invade the underground exists elsewhere with the tendency to evolve other species", he says. It has also shown that speciation does not have to be a painstakingly slow process taking place over tens of thousands to hundreds of thousands of generations, as Darwin first speculated. "A few hundred years in the right circumstances can form a new species," says Reznick. He points to the example of the marine stickleback fish in Anchorage, Alaska, which are changing genetically to adapt to freshwater environments following an earthquake in the 1960s which created new lakes there. Given that a generation in these fish lasts about a year, Reznick says speciation is occurring within 50 generations. And, unlike the London Underground mosquito, the marine and freshwater sticklebacks do not have such a distinct physical barrier between them. "This is all happening without geographic isolation," he says. I just love that it happened on Darwin's own turf and began almost the same year he wrote his book Still, with no one having examined the London Underground mosquito since Byrne in the late 1990s, he says work needs to be done to bring our understanding up to scratch.

"The genetic tools that they were using aren't the ones we'd use today. The truth is – it would be nice if someone studied the mosquitoes more closely." While Reznick has followed this speciation process in a number of organisms – from moths to flies to invasive plants – the London Underground mosquito has such a special spot in his heart that he devoted a chapter to the insects' evolution in a 2010 book he wrote on the subject of Darwin's 1859 classic Origin of Species. "I just love that it happened on Darwin's own turf and began almost the same year he wrote his book." This story is a part of BBC Britain – a series focused on exploring this extraordinary island, one story at a time. Readers outside of the UK can see every BBC Britain story by heading to the Britain homepage ; you also can see our latest stories by following us on Facebook and Twitter . Peripatric Speciation - Speciation... Speciation... Hybrids and sources PERIPATRIC SPECIATION Peripatric speciation occurs when a small group of individuals break off of the main group to form a new species.

Similar to allopatric speciation, the two groups are separated by physical barriers such as mountain ranges or waterways, making it almost impossible for the two groups to interbreed. In the smaller group that had been isolated from the parent group, there would usually be a special gene among them. This special gene could allow the particular species to develop thicker fur, longer limbs or even, in extremely rare cases, an entirely new body part! This special gene which is rare among the main group will drift to fixation due to the small number of individuals that had been isolated over the course of a few generations. This unique characteristic is what will separate and distinguish this smaller, new species from the main, parent group. As the population of the sub-group grows, more changes will begin to develop, often being characteristics that help the animal to adapt to its new environment. After several more generations, the new species will become reproductively isolated from the main species and peripatric speciation has occurred. A great example of peripatric speciation is the London Underground mosquitoes The London Underground mosquito is a form of mosquito found in the London Underground. Biologists named the London Underground mosquito Culex pipiens f. molestus due to its edacious biting.

This mosquito, was first discovered in the London Underground system, and can be found in various underground systems around the world. From being a local above-ground Culex pipiens, it gradually adapted to human-made underground systems. Recent evidence suggests it is a southern mosquito variety related to C. pipiens that has adapted to the warm underground spaces of northern cities. The evidence for this particular mosquito being a completely different species from C. pipiens comes from research done by Kate Byrne and Richard Nichols. The species have very different behaviours and are exceedingly difficult to mate. More specifically, the C. p. f. molestus, can breed all-year round, is cold intolerant and bites rats, mice, and humans, whereas the above-ground species is also cold tolerant but hibernates in the winter and bites only birds. When these two varieties were cross-bred, the eggs were infertile, suggesting reproductive isolation. So Basically: 32 Things You Did Not Know about Mosquitoes 32 Things You Did Not Know about Mosquitoes GO Aug 8, 2007 18:06 GMT · By Stefan Anitei · Share: These are the strangest females invented by nature.

But they do not ruin the life of their own males but ours. Mosquitoes are insects of the Order Diptera (thus related with the flies, even "mosquito" is a Spanish word meaning "little fly"), suborder Nematocera ("with thin antennae") and belong to the Culicidae family. 1. Mosquitoes came into being during the Jurassic Epoch, over 175 million years ago, so dinosaurs did experience the 'mosquito nightmare'... 2. There are over 3,000 varieties of mosquitoes, from the Arctic tundra to the tropical rain forests, and from the sea level to the height of Himalaya. In fact, all that mosquitoes require to remain active are temperatures over 55 ?F (12.7 ?C). Thus, they are practically anywhere, even in the desert oases, even if the highest diversity of species is encountered in wet and warm areas. 3. Most are active at dawn and dusk, sheltering during the day in dense vegetation, houses, farms but for many tropical species they are midday food. 4. Mosquitoes vary in their size: they reach 1.6-12.5 mm (0.5 inch).

Fossil mosquitoes were even 5 cm (2 inch) long. 5. Mosquitoes do not bite, they suck. 1,200,000 mosquitoes would be necessary to completely drain the average human of blood. Well, unless you die before, but of irritation. 6. An experiment in the Canadian tundra found that people who bared arms, legs and torsos reported approximately 9,000 bites per minute from swarming, newly hatched mosquitoes. In two hours, an individual could lose 50 % of his blood. 7. Only the female bites and she does this on humans but also on other vertebrates, from elephants to mice and turtles, sucking their blood. This food is necessary for the development of the ovaries and maturing of the eggs. Some species can develop without the female ingesting previously blood, but when the opportunity appears, they will do it (like in some Culex). A sole blood droplet ensures the growth of hundreds of mosquito eggs. The most exposed persons to mosquito bite are those of blood types 0 and A and younger persons. 8. The males do not bite; they eat just plant juices and nectar. 9.

The sting of the mosquito may look simple but on microscope it is extremely complicated; it is formed of 6 pieces: two tubes, a salivary one and a feeding one, surrounded by two sharp mandibles and two scalpels with saw-like teeth. All 6 pieces are wrapped in a sheath that protects them on all their length. The sting is implanted into the skin for a few mm till it reaches a minute blood vessel. 10. Mosquitoes possess olfactive and thermic organs onto their hairy pair of antennae and the three pairs of legs that head them to the their victim based on their expelled carbon dioxide, warmth and sweat. 11. Eyes occupy most of a mosquito`s head. These compound-lensed organs deliver infrared images of heat emanated from a body. 12. Male mosquito "ears" have as many sensory cells as human ears, they help males identify and pursue the females. When a mosquito tracks down the whine of the opposite sex, it begins to synchronize its own pitch to fit that of the potential mate. Males can "relate" to girl frequencies in a second or two. Females take several times longer to synchronize. 13.

Mosquitoes can mate in midair, often in just 15 seconds from approaching to fare-thee-well. 14. Mosquitoes can smell their dinner from up to 50 meters (166 ft). Mosquitoes can travel 40 miles (64 km) looking for a meal. 15. To detect you, mosquitoes use the carbon dioxide you exhale. People with high concentrations of steroids or cholesterol on their skin surface attract mosquitoes and this is a genetic trait. Mosquitoes are also attracted by uric acid present in the sweat and movement. Practicing sports in a mosquito-infested area is a bad idea as increased exhaled carbon dioxide (due to panting) and uric acid (due to sweating) turns you into a mosquitoes' magnet. 16. The blood has the ability to clot, so, through the salivary tube, the mosquito female pumps anti-clotting chemicals that keep the blood fluid, so she can suck it easily. The saliva also has an anesthetic chemical. The saliva that remains inside the skin is extremely irritating for the victim after the anesthetic effect is gone, causing an unbearable itch. 17. Do not scratch the bitten place.

The best solution is alcohol, which eases the pain. 18. The greatest problem of the mosquito bite is not the itch, but the parasites that mosquitoes, mostly in tropics, can transmit through their saliva. Anopheles mosquitoes transmit malaria, a blood parasite that kills up to 3 million people annually (over one million just in Africa) and infects 300 million people each year on the tropics. The Aedes mosquitoes are vectors for many viruses like those of the yellow fever, hepatitis or encephalitis. Dengue and West Nile viruses are also transmitted by mosquitoes. In fact, mosquitoes are considered the animals responsible for the highest number of human deaths worldwide annually. But remember: they do not transmit HIV, as the virus would die in the mosquito`s digestive system. 19. Mosquitoes can fly between the rain droplets and with 1.5-2.5 km (0.9-1.6 mi)/h at most 5 minutes at once with a wing rhythm of 250 beats/seconds! This rhythm determines their buzz and they would like not to generate it; otherwise their presence would be undetectable till they bite.

Mosquitoes can make various aerial stunts, like turns, loopings, forced landings, dives. Unlike other insects, mosquitoes and flies have just one pair of wings (not two), the second being turned into two organs that detect altitude and acceleration, allowing the insect to adapt permanently to the flight's parameters. 20. Their step on the victim is so smooth that it cannot be detected. They can even step on spider webs without the spider to feel anything!... 21. They have the rare ability of walking on the water. Only a type of water bug is known to do this (except mosquitoes). 22. In temperate zones, adult females winter in various sheltered places and when the winter is gone, they start feeding with blood and another mosquito generation is on the way. 23. Mosquitoes larvae are aquatic and as little as the water from garbage cans, old tiles, barrels, washbasins, wet basements, bathrooms, kitchens, balconies is enough to ensure their development, and combating the mosquito population in an area can result a tough task. As the larvae breathe oxygen from the air, they are not affected by the water quality. 24.

The mosquito eggs are very resistant to drought and cold, being able to resist till five years in cold and dry ground till the next warm rain and in a week, the larvae go out from the eggs. 25. There are other insects from Nematocera that look like mosquitoes, are found also around waters and are completely harmless, as their females do not suck blood and they ingest just plant sap, like midges from Chironomidae, Tipulidae (crane flies) while other diptera that do not look quite like a mosquito, from Simuliidae (black flies), Ceratopogonidae (biting midges), Glossinidae (tsetse flies) families (only some examples) but DO bite for blood and transmit extremely severe parasites, like sleeping sickness and worms that provoke river blindness, filariasis or elephantiasis. 26. The world`s largest statue of a mosquito is a local attraction in Komarno, Manitoba, the Mosquito Capital of Canada. ("Komarno" means in Ukrainian "mosquito"). The steel statue was made in 1984 and has a wingspan of 15 feet (5 m). 27.

In 1998, researchers discovered a new mosquito species in the London Underground, evolved from ancestors that flew in when the tunnels were dug 100 years ago. Once bird feeders, they now enjoy a menu of rats, mice and human blood. They do not interbreed with their aboveground counterparts. Their DNA actually varies from one subway line to another. 28. Central America`s so-called Mosquito Coast (a thin strip of land along the Caribbean in Honduras and Nicaragua) is not named after the insect, but after the indigenous Miskito Indians. 29. In Abuja, Nigeria, in 2000 the world`s biggest mosquito net was unveiled, as part of a national campaign against malaria and other insect-borne diseases. Two hundred children fit under it. 30. The best mosquito repellent is DEET, but other solutions are lemon eucalyptus oil (traded as Repel) and soybean oil, citronella, cedar, peppermint, lemongrass and geranium. Mosquito traps can also offer protection. They emit mosquitoes attracting factors, like carbon dioxide, heat, moisture and others, trapping or destroying mosquitoes.

When located in good breeding spots, they can knock mosquito populations down. 31.A radio station from Poland used an odd method of combating mosquitoes. Radio Zet emitted a continuous ultrasound signal, which even if not heard by the human ear, imitated the bat sonar and could be heard by mosquitoes. This kept away of this radio channel listeners any mosquito. 32.Some plants with prickly scent can chase away the mosquitoes, like the garlic.

Question: In 1998 a new breed of mosquito was discovered on which underground system?
Answer: London