Would it be wrong to eradicate mosquitoes?
The mosquito is the most dangerous animal in the world, carrying diseases that kill one million people a year. Now the Zika virus, which is carried by mosquitoes, has been linked with thousands of babies born with brain defects in South America. There are 3,500 known species of mosquitoes, but only the females from just 6% of species draw blood from humans - to help them develop their eggs. Of these, just half carry parasites that cause human diseases.
More than a million people, mostly from poorer nations, die each year from mosquito-borne diseases, including Malaria, Dengue Fever and Yellow Fever. Some mosquitoes also carry the Zika virus, which was first thought to cause only mild fever and rashes. However, scientists are now worried that it can damage babies in the womb. There’s a constant effort to educate people to use nets and other tactics to avoid being bitten. But would it just be simpler to make an entire species of disease-carrying mosquito extinct?
In Britain, scientists at Oxford University and the biotech firm Oxitec have genetically modified (GM) the males of Aedes aegypti - a mosquito species that carries both the Zika and Dengue viruses. These GM males carry a gene that stops their offspring from developing properly. This second generation of mosquitoes then die before they can reproduce and become carriers of disease themselves.
So are there any downsides to removing mosquitoes? Mosquitoes, which mostly feed on plant nectar, are important pollinators. They are also a food source for birds and bats while their young - as larvae - are consumed by fish and frogs. This could have an effect further ahead in the food chain. Mosquitoes also have limited the destructive impact of humanity on nature. Mosquitoes make tropical rainforests, for humans, virtually uninhabitable. Rainforests are home to a large share of our total plant and animal species, and nothing has done more to delay man-made destruction over the past 10,000 years than the mosquito.
Adapted from http://www.bbc.com/news/magazine-35408835
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