Bloodsucking Mosquitoes

Mosquitoes live worldwide except in Iceland. Males live typically 5-7 days while females live longer up to one month. Their size varies from 2mm to 6mm and typically weigh about 5mg. Average female mosquito can have a blood meal three times its weight. They can sense human target from the carbon dioxide in human breath from a distance up to 50km away. The female needs the blood for protein and iron to help her eggs develop. It feeds through a flexible tube (proboscis) which act like a drinking straw with pin-sharp end for piercing the skin. She releases her saliva into the wound. That causes slight irritation. Once her proboscis hits a blood vessel underneath the skin she injects a cocktail of chemicals into your skin, which act as a local anaesthetic and as a anticoagulant that keeps the blood in fluid form. Her saliva also contains digestive enzymes and anti-bacterial agents to control infection in their sugar meals.
Mosquitoes have a nervous system with a rudimentary brain (ganglion). Despite it small size they still seem to be outsmarting humans in the survival of the fittest. Their ability to obtain their dinner as blood suckers while avoiding host defences like nets, various chemical and ultrasound repellents, plus many predators, such as spiders, dragonflies and bats, is one of the great feats of nature.

Most species of mosquitoes are vegetarians and do not drink blood at all. They feed on plants and nectar. Out of 3,500 species only the Anopheles, Culex and Aedes are blood sucking species. It’s not known how some species of mosquitoes have evolved as blood sucking insects. Some mosquitoes do not like the blood of mammals but prefer blood of amphibians such as snakes, or birds (avian malaria).

Malaria is an ancient disease noted for more than 3000 years. The origin of malarial parasite stretches back to prehistoric Africa, where they evolved together with their human and nonhuman hosts. They contributed to the fall of Rome. They helped to turn the tide of major battles as that of Japanese against British in Burma. The Japanese, having a chronic shortage of quinine, died in their thousands from malaria during WWII, while it killed 60,000 American soldiers in the South Pacific because of shortage of quinine.

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