What is leaches?

Leaches are segmented parasitic or bloodsucking worms that belong to the Hirudinea class and are commonly found in freshwater aquatic environments such as ponds, lakes, rivers, and marshes. They are characterized by their flattened, worm-like bodies with sucker-like mouths at each end which helps them attach to the host's skin and feed on their blood.

There are over 650 species of leaches found worldwide, and they vary in size; some species can be as small as a few millimeters while others can grow up to 12 inches. They have no jaws and rely on anticoagulants that they secrete to keep the host's blood flowing while they feed.

Leeches have been used in medicine for centuries and are still used in modern medicine for reattachment surgery and to improve blood flow. Some species of leaches are also used in traditional medicine to treat various health conditions.

Overall, while leaches are a bit creepy, they serve a purpose in the ecosystem and have contributed to medical advancements.