Mosquitoes are small, midge-like flies, in fact the word “mosquito” is Spanish for “little fly”.
Mosquitoes feed on the blood of various kinds of hosts, mainly vertebrates, mainly mammals. However, some mosquitoes also attack invertebrates, birds, reptiles, amphibians, and even some kinds of fish. Although the loss of blood is seldom of any importance to the victim, the saliva of the mosquito often causes a nasty irritation that we call a bite.
However, it can be much more serious. Many species of mosquitoes act as vectors of diseases. In passing from host to host, some transmit extremely harmful infections such as malaria, yellow fever, Chikungunya, West Nile virus, dengue fever, filariasis, Zika virus and other arboviruses, rendering it the deadliest animal family in the world.
We discussed the Zika outbreak in a couple of sessions, and on the forum: http://learn-english-forum.org/discussion/3481/the-zika-virus This infographic should help to explain the causes of the Zika outbreak and possible symptoms, treatment and prevention.
When I was a child, I always wanted to be a superhero. I wanted to save the world and make everyone happy, but I knew that I’d need superpowers to make my dreams come true. So I used to embark on these imaginary journeys to find intergalactic objects from planet Krypton, which was a lot of fun, but didn’t yield much in the way of results. When I grew up and realised that science fiction was not a good source for superpowers, I decided instead to embark on a journey of real science, to find a more useful truth.
Colour is a powerful thing, and it often lies at the heart of our perception of the world. Colours help us identify specific objects and associate properties to them. Colours also help us interpret emotions and recognise real world threats. However, an interesting question is where did this sense of colour come from?
How we see in colour
It all starts with your eyes. Unlike many other living animals, human eyes are designed to interpret a wide range of light wavelengths which helps us identify colours. On a technical level, colours are simply different spectrums of wavelengths either travelling faster or slower towards our eyes and into our brain. We are good at it, but before you get big headed, we aren’t the best at interpreting colours: Many animals have a colour perception ability that is far beyond our comprehension, for example, the Mantis Shrimp: Believe it or not the mantis shrimp has 4 times better colour vision than humans do.
What is a rainbow?
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