Methane clathrate

Methane clathrate

Methane clathrate, also called methane hydrate, hydromethane, methane ice, "fire ice", natural gas hydrate or just gas hydrate, is a solid clathrate compound in which a large amount of methane is trapped within a crystal structure of water, forming a solid similar to ice...

 deposits in the ocean floor have been found to be inhabited by polychaete

Polychaete

The Polychaeta or polychaetes are a class of annelid worms, generally marine. Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are made of chitin. Indeed, polychaetes are sometimes referred to as bristle worms. More than 10,000...

 worms of the species Hesiocaeca methanicola. The worms colonize the methane ice and appear to survive by gleaning bacteria which in turn metabolize the clathrate.

In 1997, Charles Fisher, professor of biology at Penn State

Pennsylvania State University

The Pennsylvania State University, commonly referred to as Penn State or PSU, is a public research university with campuses and facilities throughout the state of Pennsylvania, United States. Founded in 1855, the university has a threefold mission of teaching, research, and public service...

, discovered this remarkable creature living on mounds of methane

Methane

Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

 ice at a depth of half a mile (~800 m) on the ocean floor in the Gulf of Mexico

Gulf of Mexico

The Gulf of Mexico is a partially landlocked ocean basin largely surrounded by the North American continent and the island of Cuba. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States, on the southwest and south by Mexico, and on the southeast by Cuba. In...

. Fisher reported that experiments with live specimens showed that the mature creatures could survive in an anoxic environment for up to 96 hours. Fisher reported that experiments showed that the larvae

Larvae

In Roman mythology, lemures were shades or spirits of the restless or malignant dead, and are probably cognate with an extended sense of larvae as disturbing or frightening...

were dispersed by currents, and died after 20 days if they did not find a place to feed.