Subscribe to our free daily newsletters
. Earth Science News .




Subscribe to our free daily newsletters



Extreme Environment Changes Fish Appearance

Amargosa River pupfish (Sean Lema/Courtesy photo)
by Staff Writers
Davis CA (SPX) Oct 16, 2006
The world of the Devils Hole pupfish is a small place. The entire species lives in one rocky pool, 20 meters long and three meters wide, in a cave entrance in Death Valley, Calif. But their environment is not only cramped: it also has a profound effect on the fishes' appearance, raising questions about how rare species can be protected from extinction.

In 1976, the inch-long fish was at the center of a legal battle that reached the U.S. Supreme Court. Conservationists had established the fish in refuges elsewhere in case Devil's Hole became too dry. But the refuge-bred fish began to look different, with deeper bodies and smaller heads, although all the fish are pretty much the same genetically.

Sean Lema, a graduate student at UC Davis, and Gabrielle Nevitt, professor of neurobiology, physiology and behavior, set out to see if environmental changes could affect how the fish looked.

They reared a related but unthreatened species, the Amargosa pupfish, in the lab on a restricted diet and with slight changes in water temperature. The Amargosa pupfish began to look more like the wild Devils Hole pupfish.

"Restricting food availability and raising the temperature just a few degrees shifts morphology dramatically," Lema said.

The findings have implications for conserving species, Lema said.

On one hand, the fish may be more adaptable to changing conditions than thought. But refuge-bred fish might well die if reintroduced directly to Devil's Hole in an attempt to rebuild the population. And if an animal's form is so intimately connected to its environment, is it still the same fish if it is not preserved in the same habitat?

"What is it that we try to preserve -- just genetics, or the habitat that makes them unique?" Lema said.

The work was supported by the National Science Foundation and is published in the Sept. 15 issue of the Journal of Experimental Biology. Lema is currently a researcher at the NOAA Northwest Fisheries Science Center in Seattle and at the University of Washington.

Related Links
UC Davis
Learn about Climate Science at TerraDaily.com

Marine Life Stirs Ocean Enough To Affect Climate
Tallahassee FL (SPX) Oct 16, 2006
Oceanographers worldwide pay close attention to phytoplankton and with good reason. The microscopic plants that form the vast foundation of the marine food chain generate a staggering amount of power, and now a groundbreaking study led by Florida State University has calculated just how much -- about five times the annual total power consumption of the human world.







  • China Ready For Refugee Rush After North Korean Nuclear Test
  • FEMA Signing Statement Blasted
  • North Korea Braces For Sanctions
  • Inter-Korean Projects In Jeopardy

  • Extreme Environment Changes Fish Appearance
  • Marine Life Stirs Ocean Enough To Affect Climate
  • NASA Live Tropical Seas Surface Temperature Website Gives Climate, Hurricane Clues
  • Northern Bogs May Have Helped Kick-Start Past Global Warming

  • Deimos And Surrey Satellite Technology Contract For Spanish Imaging Mission
  • NASA Satellite Data Helps Assess the Health of Florida's Coral Reef
  • Alcatel Alenia Space To Build SIRAL-2 Radar Altimeter For CryoSat-2
  • Earth from Space: The French Frigate Shoals

  • A Boost For Solar Cells With Photon Fusion
  • Think-Tank To Focus On Aluminium Industry Sustainability
  • China Poses No Threat To Global Energy Supply
  • Harvesting Machine Driving Mesquite-to-Ethanol Potential

  • West Java Goes Own Way On Avian Flu Management
  • A Biocontrol Agent Which Doesn't Trigger Antibiotic Resistance
  • US, Australian Scientists Develop Vaccine Against Deadly Viruses
  • 'Killer' B Cells Provide New Link In The Evolution Of Immunity

  • Comparing Chimp And Human DNA
  • Embryo Fossils Reveal Animal Complexity 10M Years Before Cambrian Explosion
  • Possible Evidence Of Cell Division, Differentiation Found In Oldest Known Embryo Fossils
  • Bacterial Intelligence

  • 300 Million US Consumers Make A Vast Environmental Footprint
  • South Korea Says No Unusual Radiation After North Korean Test
  • More Than 950 Children In Northwest China Suffer Lead Poisoning
  • Canadin Prime Minister Says New Clean Air Act Coming

  • American Population About To Pass 300 Million Mark
  • Rapid Rise In The Arctic Ocean May Alter Views Of Human Migration
  • Democrat Push For Wellness Agency
  • More Than Meets The Human Eye

  • The content herein, unless otherwise known to be public domain, are Copyright 1995-2006 - SpaceDaily.AFP and UPI Wire Stories are copyright Agence France-Presse and United Press International. ESA PortalReports are copyright European Space Agency. All NASA sourced material is public domain. Additionalcopyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by SpaceDaily on any Web page published or hosted by SpaceDaily. Privacy Statement