Pierson's Puppeteer

The Pierson's puppeteers, also known as simply "puppeteers", are an alien race of sentient creatures from Larry Niven's Known Space novels.

Physiology

The puppeteers' bodies are composed of one hind leg and two forelegs, and a torso which houses the brain in a hump located between its two heads. These heads have mouths with lips which look like fingers in a glove, hence the name "puppeteer" which was given to them by Pierson, a crewman from one of Niven's novels who was the first person to ever see one of their species. There is an eye on each head, and each mouth has a forked tongue much like a snake's. These mouths are capable of manipulating objects much in the same way a human would use hands. They are capable of imitating human speech as well as the Hero's Tongue, the Kzinti speech, although their own native language is described as sounding like orchestral music.

They are herbivores who live in herds, and have a very long lifespan which can span centuries. They seem to have three genders, although the puppeteers are loath to discuss it among those outside of their species. Two of these genders are labeled as "male"; however, they are hermaphroditic. The third gender, labeled "female", is actually a non-sentient creature used as a sort of host for the offspring. As a result, all the puppeteers which are born are "male", while the "females" breed amongst themselves to create more females.