by Alexa (age 9, @KNEstemGirls)
Have you seen a leech before? They’re super cool! Leeches are worm-like animals. Their nearest relatives are earthworms. Most people think that leeches are like monsters because they suck blood, but they are very useful to humans. For example, the nervous system of a leech is very similar to the human nervous system so it is an enormous benefit to researchers in their quest for the answers to human problems. Also, the original surgeons were barbers and they used leeches to cure anything from headaches to gout.
Leeches can have 2 to 10 eyes depending on the species, breath through their skin, and have up to 32 brains. The largest leech discovered measured 18 inches.
If you do see a leech, you shouldn’t be scared. Not all leeches suck blood. The ones that do sometimes use different methods. The Amazon leech inserts a long proboscis into the victim, as opposed to biting. The Hirudo leech injects an anti-coagulant serum into the victim’s blood to prevent blood clotting.
Once a leech has bitten you, it will gorge itself until it has had its fill and then just fall off. It will eat up to 5 times its body weight. When the leech has finished feeding it might not eat again for months. Leeches are super cool!