Why You Should Plan to Deliver in the Fall

Babies born in spring are slightly more likely to develop anorexia nervosa (an eating disorder characterized by extremely low body weight, distorted body image and an obsessive fear of gaining weight), while those born in the fall have a lower risk, say researchers.

A report published in the British Journal of Psychiatry suggests temperature, sunlight, infection or the mother’s diet could be responsible.

Other academics said the effect was small and the disorder had many causes.

The researchers analysed data from four previous studies including 1,293 people with anorexia.

The researchers found an “excess of anorexia nervosa births” between March and June – for every seven anorexia cases expected, there were in fact eight.

There were also fewer than expected cases in September and October.

Dr Lahiru Handunnetthi, one of the report’s authors, at the Wellcome Trust Centre for Human Genetics, said: “A number of previous studies have found that mental illnesses such as schizophrenia, bipolar disorder and major depression are more common among those born in the spring – so this finding in anorexia is perhaps not surprising.

Screening methods

“However, our study only provides evidence of an association. Now we need more research to identify which factors are putting people at particular risk.”

The report suggests seasonal changes in temperature, sunlight exposure and vitamin D levels, maternal nutrition and infections as “strong candidate factors”.

Dr Terence Dovey, from the Centre for Research into Eating Disorders, at Loughborough University, said: “Anorexia is a very complex multifaceted disorder,” adding that the study looked at just one aspect.

“Should we concentrate screening methods to those born in the winter months? No, we should not. It leaves too much error of margin and the potential significant difference is only small.”

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Using Mosquitoes To ‘Vaccinate’ Against Malaria

Joanne Silberner,NPR

The parasite responsible for the intense fevers, chills, and headaches of malaria is very skilled at hiding in the in the body. That means vaccines don’t work all that well to prevent the disease.

So Dutch researchers are trying a new approach — “vaccinating” people by having them get bitten by mosquitoes carrying the malaria parasite, which is similar to how people get infected in the real world. And it seems that this technique may keep people safe from the disease more than two years later.

The Dutch way is different than the conventional vaccine approach of injecting people with bits and pieces of the malaria parasite, or a parasite that’s been weakened in the lab.

Those traditional approaches haven’t been working all that well in clinical trials. The Plasmodium parasite is notoriously tough to manipulate because it spends most of its time hiding inside red blood cells and liver cells, out of sight of the immune system. That’s one reason why it was able to kill 781,000 people in 2009. Most of those were children in developing countries.

In the Dutch experiment, 10 volunteers were bitten multiple times by malarious mosquitoes. The researchers then gave the volunteers an anti-malaria drug, chloroquine. (And yes, the researchers were very careful to pick a malaria type that can be vanquished by chloroquine, not a variety resistant to the drug.)

A couple of years ago, the researchers reported that this process works in the short run to protect against malaria. But that’s not such a big deal. People naturally infected by malaria build up an immunity that holds for several months.

What’s new is that the researchers went back to six of the volunteers 28 months later. Once again the volunteers allowed themselves to be bitten by malarious mosquitoes. Four of the six did not get infected. And the immune systems of the remaining two put up a fight – their infections were delayed (and quickly treated). The results were published online in The Lancet.

Wondering who would volunteer to be bitten by a malarious mosquito? Study author Robert Sauerwein of Radboud University in the Netherlands says most were university students. And the trial was designed pretty carefully.

A lot more work needs to be done to test this approach. This study was very small – only six people. And the researchers note that they may have stacked the deck a little – they used the exact same strain of malaria to infect, and to re-infect. And they worked with adults with mature immune systems, rather than children.

It’s not clear yet why the experimental vaccination protected longer than infection by mosquito in the field. The anti-malarial drug could have helped. Or maybe it was the intense exposure to multiple bites at the same time. Whatever the reason, they say, it’s worth investigating given how well the malaria parasite has been at outsmarting attempts to get rid of it.

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Genetically Modified Mosquitoes Offer Malaria Hope

By James Gallagher Health and Science reporter, BBC News

Scientists believe they are closer to being able to change the DNA of wild mosquitoes in order to combat malaria.

In the laboratory, they made a gene spread from a handful of mosquitoes to most of the population in just a few generations, according to a report in Nature.

If the right gene can be made to spread then researchers hope to reduce the number of cases of malaria.

Other academics have described the study as a “major step forward”.

The World Health Organisation estimated that malaria caused nearly one million deaths in 2008.

Spreading resistance

Around a million people are thought to die from malaria each year

Research groups have already created “malaria-resistant mosquitoes” using techniques such as introducing genes to disrupt the malaria parasite’s development.

The research, however, has a great challenge – getting those genes to spread from the genetically-modified mosquitoes to the vast number of wild insects across the globe.

Unless the gene gives the mosquito an advantage, the gene will likely disappear.

Scientists at Imperial College London and the University of Washington, in Seattle, believe they have found a solution.

They inserted a gene into the mosquito DNA which is very good at looking after its own interests – a homing endonuclease called I-SceI.

The gene makes an enzyme which cuts the DNA in two. The cell’s repair machinery then uses the gene as a template when repairing the cut.

As a result the homing endonuclease gene is copied.

It does this in such a way that all the sperm produced by a male mosquito carry the gene.

So all its offspring have the gene. The process is then repeated so the offspring’s offspring have the gene and so on.

In the laboratory experiments, the gene was spread to half the caged mosquitoes in 12 generations.

Defeating malaria

Professor Andrea Crisanti, from the department of life sciences at Imperial College London, said: “This is an exciting technological development, one which I hope will pave the way for solutions to many global health problems.

“At the beginning I was really quite skeptical and thought it probably would not work, but the results are so encouraging that I’m starting to change my mind.”

He said the idea had been proved in principle and was now working on getting other genes to spread in the same way.

He believes it could be possible to introduce genes which will make the mosquito target animals rather than humans, stop the parasite from multiplying in the insect or produce all male offspring which do not transmit malaria.

Professor Janet Hemingway, from the Liverpool School of Tropical Medicine, said the work was an “exciting breakthrough”.

She cautioned that the technique was still some way off being used against wild mosquitoes and there were social issues around the acceptability of using GM technology.

“This is however a major step forward providing technology that may be used in a cost effective format to drive beneficial genes through mosquito populations from relatively small releases,” she added.

Dr Yeya Touré, from the World Health Organisation, said: “This research finding is very important for driving a foreign gene in a mosquito population. However, given that it has been demonstrated in a laboratory cage model, there is the need to conduct further studies before it could be used as a genetic control strategy

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Human Speech Originated in Africa: Study Suggests

Human speech originated in central and southern Africa, according to new research on languages. It is then said to have spread around the globe alongside migrating human populations.

A comprehensive study of phonemes, or the perceptually distinct units of sound that differentiate words, used in 504 human languages reveals that the dialects containing the most phonemes are spoken in Africa, those with the fewest in South America and on tropical islands in the Pacific Ocean.

This pattern of phoneme usage around the world mirrors the pattern of human genetic diversity, which also declined as humans expanded their range from Africa to colonize other regions, reveals an analysis in the 15 April issue of Science

Data compiled by Quentin Atkinson from the University of Auckland, shows a movement of languages out of the African continent to other areas of the world. Atikson says, “It seems like the obvious explanation is that people carried language – along with their genes – with them as they expanded out of Africa.”

Atkinson’s findings further reveal that areas that were most recently colonised adapt fewer phonemes into their local languages while regions that have hosted human life for a long time still use the most phonemes, sub-Saharan Africa in particular.

According to Atkinson’s study, the highest levels of phonemic diversity are found in language families associated with the people of Southeast Asia. His research frames comple language as one of the earliest archaeological symbols of mordern human culture, indicating that it was a key cultural innovation that ultimately led to our colonisation of the globe.

In conclusion Atkinson says: “Modern humans are just one big, genetic family with a single common ancestor, one of the things I like about these results is that, to the extent that language is an identity, we all seem to be part of one big, cultural family as well.”

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Resource-rich Africa Well Placed to Transition to ‘Green Economy’ – UN official

Windmills along the coast of Tunisia, (picture-alliance/dpa)

28 March 2011 –Africa is well poised to take advantage of a host of opportunities on the continent for building a ‘green economy,’ one that generates decent jobs in an environmentally sustainable way, a senior United Nations official said today.

“This continent is in many ways the envy of the 21st century world,” Achim Steiner, Executive Director of the UN Environment Programme (UNEP), told African ministers of finance, planning and economic development gathered in Addis Ababa, Ethiopia.

“Africa is rich in the kinds of natural resources that in many parts of the world have been over-exploited and diminished by centuries of unsustainable development,” he stated.

This includes not just precious and semi-precious metals, but also nature-based resources such as forests and biodiversity, which support tourism and could also underpin inventions and pharmaceutical breakthroughs.

At the same time, many parts of the continent are rich in so-called natural fuels such as wind, solar and geothermal.

“The fundamental question,” said Mr. Steiner, “is how will all this potential be harvested for the benefit of Africa’s citizens and in a way that promotes stability in Africa and beyond.”

He noted that the green economy is not a substitute for sustainable development, but a way of realizing it. “It is as relevant to developing economies and it is to developed ones; it is as central to more state-led economies as it is to more market-led ones. It is not a straitjacket, nor is it prescriptive.”

In February UNEP released a report outlining how investing 2 per cent of global gross domestic product (GDP) in 10 sectors can catalyze the transition to a green economy.

It also provided a global compilation of case studies from across the globe, including Africa, where forward-looking policies by governments are “watering the green shoots” of the global green economy.

One example is South Africa, whose Green Economy Plan focuses on investments that create more decent jobs, and where nearly $1 billion is being spent on railways, energy-efficient buildings, and water and waste management.

He also highlighted Kenya’s new green energy policy, including a feed-in tariff and 15-year power purchase agreement, which is catalyzing an initial target of 500 megawatts of energy from geothermal, wind and sugar wastes systems.

Later this week, Secretary-General Ban Ki-moon will visit Kenya’s main geothermal sites, located north-west of Nairobi, to learn first-hand how these developments have been achieved, as well as how they are set to generate thousands of new jobs in the clean energy sector while reducing dependency on imported fossil fuels.

“The rest of the world can learn from Africa, but Africa can also learn from other continents,” said Mr. Steiner.

He added that the upcoming UN Conference on Sustainable Development, set to be held in Rio de Janeiro in June 2012 – 20 years after the Earth Summit of 1992, could prove to be one of the most transformative moments in international affairs.

“In 1992, we could only perhaps glimpse the scale some of the challenges emerging on the radar from climate change and the loss of healthy, productive cropland,” he noted.

“But in the world of the here and now, many of those challenges have become all too real. There is an urgency to swiftly and decisively evolve the sustainable development agenda onto a far more focused and far reaching level.”

He said that the question now emerging is not whether a green economy is desirable but how to realize a green economy in practical terms.

“Rio+20 offers an opportunity to accelerate and scale-up transitions, already under way across this region and indeed across the world in order to catalyze growth and employment opportunities for around nine billion people by 2050,” he stated. “But in a way that also maintains and enhances the regional and global planetary services that underpin wealth generation in the first place.

“Africa’s experience on what has worked and what has not worked over the past two decades offers an invaluable foundation upon which a transformational outcome next year can be built.”

UN News Center
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A Green Economy Statement by Achim Steiner to African Ministers of Finance, Planning and Economic Development

Delivered at the 2011 Joint Annual Meetings of African Union Conference of Ministers of Economy and Finance and the Economics Commission for Africa Conference of African Ministers of Finance, Planning and Economic Development

28 March 2011- Addis Ababa, Ladies and Gentlemen,

We meet some 13 months before what could prove to be one of the most transformative moments in international affairs.

Nearly 20 years after the Earth Summit of 1992-which established much of the sustainable development of the intervening years-nations are again traveling on the Road to Rio for the UN Conference on Sustainable Development 2012-or Rio+20.

In 1992, we could only perhaps glimpse the scale some of the challenges emerging on the radar from climate change and the loss of healthy, productive cropland.

But in the world of the here and now, many of those challenges have become all too real-there is an urgency to swiftly and decisively evolve the sustainable development agenda onto a far more focused and far reaching level.

There is now an essential need to implement the vision of 1992.

Two themes have been agreed in order to achieve that.

A Green Economy in the context of sustainable development and poverty eradication.

An International Framework for Sustainable Development.

What do they mean for the world and what do they mean for Africa in particular?

To my mind they could mean quite a lot if the countries of this Continent decide to fully engage on these twin agendas and through the numerous preparatory meetings of the coming months and year.

On the one hand the nations of this Continent face the same challenge that now faces every country on Earth.

How to grow and how to generate good and decent jobs, but in a way that does not push humanity’s footprint beyond planetary boundaries.

But Africa has many challenges and opportunities that are unique.

While not diminishing the challenges, let me set aside these issues as they are well known and familiar to everyone in this room.

Let me instead dwell on the opportunities.

Firstly, this Continent is in many ways the envy of the 21st century world.

Africa is rich in the kinds of natural resources that in many parts of the world have been over-exploited and diminished by centuries of unsustainable development.

Many rapidly developing economies are also finding scarcities are now emerging too.

I am not just referring to precious and semi-precious metals.

But also nature-based resources such as forests and biodiversity-biodiversity that underpins tourism, but which will also underpin the inventions and pharmaceutical breakthroughs of the emerging biological age.

Land too, which as we know, is increasingly attracting investors from overseas for growing crops to feed their growing and more affluent populations.

Meanwhile, many parts of this Continent are rich in what one might term natural fuels-wind, solar, geothermal; hydro both large and small and perhaps soon the possibility of wave energy.

Meanwhile Africa is now undergoing some of the fastest-if not the fastest-urbanization rates in the world and in many places and in many ways almost from scratch.

I could go on. But the fundamental question is how will all this potential be harvested for the benefit of Africa’s citizens and in a way that promotes stability in Africa and beyond.

In an economic mode of the 20th century-or in a way that maximizes the true value of these resources.

In a way that weighs all the economic, social and environmental options rather than just one or two-

Will Africa’s forests be exported as logs to overseas buyers?or will they be managed in ways that reflect not only their commodity value but their multi-trillion dollar services they provide for the Continent but also the world?

Will the urbanization of Africa leapfrog the unsustainable paths of Europe, the United States or the development paradigms of many rapidly emerging economies in Asia or Latin America?

Because the fact is that in many parts of the world, countries will have to re-build and retrofit sustainability into their economies if sustainable development is to be realized.

Whereas in Africa you have the chance to build it up and build it into your growth early on.

Honorable delegates, ladies and gentlemen,

UNEP’s work on the Green Economy and now the work of many organizations and institutions world-wide have gone from theory to the potential for a new development reality in just two to three years.

It is not a substitute for sustainable development, but a way of realizing it.

It is as relevant to developing economies and it is to developed ones: it is as central to more state-led economies as it is to more market-led ones.

It is not a straight-jacket, nor is it prescriptive.

The Green Economy is about shaping public policy including market mechanisms and fiscal strategies in a way that unleashes the private sector into a more meaningful notion of wealth creation that achieves the aims outlined above.

Our report-Towards a Green Economy-which was presented to environment ministers attending UNEP’s Governing Council in Nairobi in February, outlined how investing 2 per cent of global GDP in 10 sectors can catalyze that transition.

It also provided a global compilation of case studies from across the globe, including Africa, where forward-looking policies by governments are watering the green shoots of that Green Economy everywhere.

  • Uganda – policies to promote organic agriculture have generated 200,000 certified farmers and exports growing from close to $4 million in 2003 to nearly $23 million now
  • Rwanda’s initiative on forest ecosystem restoration is another landmark in the shift
  • The Democratic Republic of Congo’s accessing of the emerging potential under the UN’s Reduced Emissions from Deforestation and forest Degradation (UN-REDD) is another.
  • The solar power partnership between countries in North Africa and European companies under Desertech promises to be transformational.
  • South Africa’s Green Economy Plan with a primary focus on investments that create more decent jobs, and related to this, investments in infrastructure-nearly $ 1 billion is being spent in railways, energy efficient buildings, and water and waste management..
  • Kenya – its new green energy policy, including a Feed-In Tariff and 15 year power purchase agreement, is catalyzing an initial target of 500MW of geothermal, wind and sugar wastes-into-energy systems: a rise in the country’s installed capacity of over 40 per cent.

Indeed later this week UN Secretary-General Ban ki-moon will visit Kenya’s main geothermal sites north west of Nairobi to learn at first hand how these developments have been achieved.

And how they are also set to generate thousands of new jobs in the clean tech, clean energy sector while reducing dependency on imported fossil fuels.

UNEP is in discussions as to how to integrate and computerize all these different renewable energy components in order to maximize efficiencies in the evolving Kenyan grid and in ways that may also benefit the planned East African Power Pool.

The rest of the world can learn from Africa, but Africa can also learn from other Continents.

Currently only 25 per cent of the world’s waste is reused or recycled-a waste of raw materials and a waste of opportunities for transforming hazardous, informal jobs into decent, formal ones.

  • The Republic of Korea has, through a policy of Extended Producer Responsibility, enforced regulations on products such as batteries and tyres to packaging like glass and paper, triggering a 14 per cent increase in recycling rates and an economic benefit of $1.6 billion
  • Brazil’s recycling already generates returns of $2 billion a year, while avoiding 10 million tones of greenhouse gas emissions; a fully recycling economy there would be worth 0.3 per cent of GDP

Ladies and gentlemen,

As we head down this Road to Rio, the question now emerging is not whether a Green Economy is desirable but how to realize a Green Economy in practical terms.

Firstly, all countries are at different points in their development path and with different mixes of sectors.

How you realize a Green Economy in say Nigeria or Mauritania will no doubt be different in say South Africa, Sudan or Gabon.

Secondly, it is loud and it is clear that good public policy is central and that the cross fertilization of experience and directions already being implemented in and outside Africa are invaluable.

Third, directing domestic investment flows into sustainable wealth generation that reflects national circumstances, deals with multiple challenges and realities and maximizes multiple opportunities is key.

Fourth-the role of the international lending and financing institutions, from the World Bank and the International Monetary Fund to regional development banks and bilateral assistance flows, need to support national transitions to a Green Economy.

Rio+20 offers an opportunity to accelerate and scale-up transitions, already underway across this region and indeed across the world in order to catalyze growth and employment opportunities for around nine billion people by 2050.

But in a way that also maintains and enhances the regional and global planetary services that underpin wealth generation in the first place.

Africa’s experience on what has worked and what has not worked over the past two decades offers an invaluable foundation upon which a transformational outcome next year can be built.

Africa’s determination to adopt a low carbon, resource efficient Green Economy development path can also inspire others to take the kinds of next steps that can ensure that both poverty eradication and wealth generation happens faster for those that need it most.

Africa’s decision to engage fully on the Road to Rio will make it an equal partner in a new era where sustainability, equity and fairness win out over instability, imbalance and the interests of the few over the many.

Indeed investing analytical and political capital in this process may be one of the best investments that you as ministers could make in Africa’s future.

It may well define Africa’s strategy for new kinds of wealth generation that in turn may define a new and more sophisticated era of trade and cooperation with the rest of the world and a fast track to prosperity for many if not all of this Continent’s citizens.

United Nations Environment Programme
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Early Humans Began in Southern Africa, Study Suggests

By Mark Kinver Science and environment reporter, BBC News

Modern humans may have originated from southern Africa, an extensive genetic study has suggested.

Data showed that hunter-gatherer populations in the region had the greatest degree of genetic diversity, which is an indicator of longevity.

It says that the region was probably the best location for the origin of modern humans, challenging the view that we came from eastern Africa.

The study appears in the Proceedings of the National Academy of Sciences.

Hunter-gatherer groups in southern Africa were among the most genetically diverse populations

“Africa is inferred to be the continent of origin for all modern human populations,” the international team of researchers wrote.

“But the details of human prehistory and evolution in Africa remain largely obscure owing to the complex histories of hundreds of distinct populations.”

‘Very exciting’

Co-author Brenna Henn, from Stanford University, California, said the team’s study – the most comprehensive of its kind – reached two main conclusions.

“One is that there is an enormous amount of diversity in African hunter-gatherer populations, even more diversity than there is in agriculturalist populations,” she told BBC News.

This is a landmark study, with far more extensive data on… hunter gatherer groups than we have ever had before, but I am cautious about localising origins from it”

“These hunter/gatherer groups are highly structured and are fairly isolated from one another and probably retain a great deal of different genetic variations – we found this very exciting.”

Dr Henn added: “The other main conclusion was that we looked at patterns of genetic diversity among 27 (present-day) African populations, and we saw a decline of diversity that really starts in southern Africa and progresses as you move to northern Africa.”

She explained that the team’s modelling was consistent with the serial founder effect. This refers to a loss of genetic variation when a new population is established by a very small number of individuals from the original, larger population.

“Populations in southern Africa have the highest genetic diversity of any population, as far as we can tell.

“So this suggests that this might be the best location for (the origins) of modern humans.”

‘Landmark study’

Chris Stringer, a leading palaeontologist based at the Natural History Museum, London, said: “The new paper… suggests that the genes of the Namibian and Khomani bushmen (southern Africa), Biaka pygmies (Central Africa) and the Sandawe (East Africa) appear to be the most diverse, and by implication these are the most ancient populations of Homo sapiens.”

Professor Stringer, who was not involved in the study, added: “This is a landmark study, with far more extensive data on… hunter gatherer groups than we have ever had before, but I am cautious about localising origins from it.”

He said that the ranges of these groups were currently quite limited, but rock paintings by ancient populations that had been linked to the Bushman hinted that they were once far more widespread.

“It seems more likely that the surviving hunter-gatherer groups are now localised remnants of populations that formerly ranged across much of sub-Saharan Africa 60,000 years ago,” he told BBC News.

Professor Stringer said that he no longer thought that there was a single “Garden of Eden” where we evolved. Instead, he said, “distinct populations in ancient Africa probably contributed to the genes and behaviours that make up modern humans”.

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A Smelly Experiment: Mosquito-Eating Spider Likes Smelly Socks

Not the most appealing-looking house guest, but it could help combat malaria
Victoria Gill

A spider that preys on the malaria-carrying mosquito Anopheles gambiae is attracted to the odor of sweaty socks, according to a study.

Scientists in the UK and Kenya used previously worn socks in an experiment to find out if the spider, like its prey, was attracted to human odors.

The jumping spider appears to have evolved an affinity for smelly human feet in order to help find its prey.

The team reports its findings in the journal Biology Letters.

They say that people might be able to “recruit” this East African jumping spider, Evarcha culicivora , in the battle against malaria by encouraging the arachnids to live in their homes.

Smelly experiment

Fiona Cross, from the University of Canterbury, and Robert Jackson, from the International Centre of Insect Physiology and Ecology (ICIPE) in Kenya, carried out the study.

They were interested in this species because it is the only known predator that specifically preys on blood-carrying mosquitoes.

“We had a suspicion that human odor was attractive to the spiders before we even ran the experiment,” Ms Cross told BBC News. “We generally find these spiders in the tall grass next to houses or other buildings occupied by people.”

To test this suspicion, the team devised an aroma-based experimental set-up called an olfactometer.

They put each “test spider” into a small holding chamber into which air was pumped, either from a box containing a clean sock or one containing a worn (and therefore

The jumping spiders can kill 20 mosquitoes in one "feeding frenzy"

smelly) sock.

Each spider was able leave its holding chamber at any time and escape into an exit chamber, which did not have sock-scented air pumped into it.

The spiders supplied with the aroma of worn socks always remained in the holding chamber for longer than those exposed to the freshly washed sock.

Ms Cross said it was “unprecedented that a spider should find human odour attractive”.

But, she added, the discovery tied in with some of the spiders’ remarkable behaviour.

“When they smell blood, they can launch into feeding frenzies where they kill up to 20 mosquitoes in rapid succession, and not necessarily to eat all of them,” she explained.

“We need to learn more about why they do this – they really do go quite crazy when they are in the vicinity of blood.”

Anti-malaria arachnid

It may be a rather ugly, bloodthirsty little creature, but Evarcha culicivora could help in the ongoing and complex battle against malaria.

“It’s something that’s there in the environment for free,” said Ms Cross. “So why not do what we can to find out about this remarkable predator?”

She and her colleagues are currently trying to find out what exactly people might be able to do to attract the spiders into their homes, without also attracting the mosquitoes.

The scientists say that, in malaria zones, people should welcome these particular creepy crawlies into their houses.

(Read the Scientific Article From Biology Letters)

(Victoria Gill, Science and nature reporter, BBC News)
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