A Thark is a Green Martian
. As described by Edgar Rice Burroughs
, they stand about fifteen feet tall and would weigh about 400 pounds on Earth. They are green and have four arms. Extremely warlike, they do not wear clothing but adorn themselves with silver bangles and battle harness, and are usually encountered bearing several spears, knives, and rifles that have an effective combat range of about 200 miles (in Barsoom
's atmosphere). They have huge tusks coming from their lower jaws, tiny cup-shaped ears at the tops of their heads, and large white eyes with red pupils on the sides of the heads. They are hairless and have no visible sex organs. Females are built the same as males, but are shorter, have longer tusks and a slightly lighter colour. They are all equally ferocious, but most thark warriors seem to be male.
Young tharks are hatched in communal clutches of several hundred round eggs. Their life expectancy is about 300 years, but would be closer to 1000 years if they were not so prone to dying by violence. The twenty tharks in a thousand that do live so long take a voluntary pilgrimage down the River Iss, whence no living Martian returns.
Communication amongst tharks, as with all Barsoomians, is mostly by telepathy. Their spoken language is extremely simple.
Tharks are merciless warriors with almost no regard for anyone else's life, and John Carter reports seeing many cases of tharks executing others for the most minor lapses in judgement. In the first Barsoom book, Carter's watchdog is nearly shot for not being able to prevent his escape, although no thark warrior is ever able to accomplish that same task. Naturally, Carter saves the watchdog, which accompanies him through several books afterwards.