Deep-Sea Vents Harbor
Earth’s Hottest Animal

University of Delaware marine scientist Craig Cary recently discovered that an inhabitant of the deep sea is the most heat-tolerant animal on Earth. The Pompeii worm (Alvinella pompejana) can survive an environment as hot as 80° C (176° F) — nearly hot enough to boil water. How the worm survives this heat remains a mystery.

Formerly, the Sahara desert ant was believed to be the most heat-hardy creature, foraging briefly in the desert sun at temperatures up to 55° C (131° F).

Cary’s research was conducted onboard the deep-sea submersible Alvin at hydrothermal vent sites in the Pacific Ocean west of Costa Rica. Using a long temperature probe called “the Mosquito,” he found that the worm’s rear end sits in water as hot as 80° C (176° F), while its head, which sticks out of the worm’s tube home, rests in water that is much cooler, about 22° C (72° F).

Covering the Pompeii worm’s back is a fleece of bacteria that can also “take the heat.” These bacteria are of particular interest to industry because they may harbor enzymes that are useful in such high-temperature applications as processing food and drugs, making paper, and dislodging oil inside wells. By learning more about the unique biology of the Pompeii worm and other “extremophiles” — organisms that thrive in extreme temperature and pressure conditions — scientists may open the door to beneficial new products and processes.
 
Photo right: If you look closely at the lower right-hand quadrant of this photo, you can see a Pompeii worm extending its dark-red feathery head and paler body from its tube home. The worm is about 13 centimeters (5 in) long.