Printer Friendly

Animals at the hydrothermal vents.

Eight years ago, biologists were startled by the discovery of large communities of animals, including clams, crabs, mussels and worms, at hydrothermal vents deep under the ocean at the /77, p.279). These animals are nourished not by photosynthetic food sources but by microbes that efficiently use chemicals modified by geothermal energy. Since then at least four additional vent communities have been found. So far, more than 30 newly discovered species in 16 previously unknow families have been observed at the vents. J. Frederick Grassle of the Woods Hole (Mass.) Oceanographic Institute describes in the Aug. 23 SCIENCE similarities in the distribution of animals at vent communities in the Pacific Ocean and in the gulf of Mexico, including the intriguing "co-occurrence" of a clam, a mussel and a vestimentiferan, or tube, worm at widely separated sites.

The vent communities are at least 200 million years old; yet the life span of a vent is at most a few decades. Therefore the animals must repeatedly colonize new vents tens and occasionally hundreds of kilometers away. "Under these circumstances, uld expect that there would be strong selection for rapid growth, the ability to produce many offspring, and an efficient means of dispersal," Grassle says.

He reports that the rates of metabolism, growth and fecundity are higher in organisms living at the vents than in other deep-sea organisms. The metabolic rates of the largest vent animals are similar to those of shallow-water relatives, and many times higher than those of deep-sea relatives. "Studies of the vents," Grassle says, "have laid to rest the idea that constraints of pressure and temperature alone limit the activities of deep-sea organisms."
COPYRIGHT 1985 Science Service, Inc.
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 1985, Gale Group. All rights reserved. Gale Group is a Thomson Corporation Company.

Article Details
Printer friendly Cite/link Email Feedback
Title Annotation:animal communities at deep-sea hydrothermal vents
Publication:Science News
Date:Aug 24, 1985
Words:274
Previous Article:'Ptarmigans wheeling over the gorse'; surely such things don't happen with mathematics ... but, au contraire, they do.
Next Article:Canteen for a young lizard.
Topics:


Related Articles
On the scent of Gorda ridge vents.
Clams and worms fueled by gas?
Large warm spot in the Pacific.
Superhot fluids from ocean bottom.
Light at the bottom of the ocean.
New type of hydrothermal vent looms large.
Some like it hotter. (Extremophiles).
Nearly naked: large swath of Pacific lacks seafloor sediment.
COMMUNITIES BRIEFLY.
COMMUNITIES CALENDAR.

Terms of use | Copyright © 2016 Farlex, Inc. | Feedback | For webmasters