Why do scientists like to give every organism its own scientific name?

That way it's easier to identify. Most of them have Greek and Latin roots which define the organisms properties through just it's name.

a motor homunculus represents a map of brain areas dedicated to motor processing for different anatomical divisions of the body.

homunculus represents the importance of various parts of your body as seen by your brain. as a result, they take up a lot of brain space. although the cortical homunculus is a curiosity, penfield's work in mapping the brain's relationship to the body was invaluable.

one would be wind another would be water density