under the radar

leeches

  Leeches are types of worms. Their closest relatives are earthworms. There are over 650 species of leeches. They differ in size, type of diet and habitat. Leeches usually inhabit marshes, rivers and ponds. One fifth of all leeches live in the sea, while certain species live attached to the forest vegetation. The most popular species of leeches is Hirudo medicinalis, better known as medical leech. It is used for several medical procedures. Unfortunately, number of medical leech in the wild is decreased due to habitat loss (as a result of increased agriculture), water pollution and introduction of invasive species. It is listed as endangered species. 

 

  Leech has 32 brains. Due to similarity with the nervous system of humans, leeches are often used in the investigations of brain disorders.  Leeches have huge appetite. They can ingest amount of blood that is five times bigger than their own weight. Once they are full, leeches will detach from the victim.Since they are able to eat a lot in a single meal, leeches can survive without food period of one year. 

Leeches are hermaphrodites which mean they have both male and female reproductive organs.Leeches are able for self-reproductions (they do not require partner for reproduction). They produce large number of eggs and lay them either in a cocoon or store them in their own body. They can survive loss of 9/10 of their body weight and exposure to heavy chemicals.Different species of leeches have different lifespan. Some leeches can survive up to 10 years!