BSCS Biology: A Molecular Approach Unit 1:
Energy, Matter, and OrganizationIn the NewsNew Ecosystem Discovered in Atlantic Ocean Imagine finding a lost city the likes of which scientists have never seen
before. Its towering structures have lain hidden hundreds of meters below
the ocean floor. Even now it is occupied by residents that thrive in a most
bizarre, previously unknown environment. This sounds a bit like Atlantis, the lost island city of myth that supposedly
lies veiled under the ocean surface. However, this lost city is home not to
an ancient civilization, but to an unusual collection of creatures −
tiny crustaceans and hydrogen- and methane-consuming microbes living around
a newly discovered thermal vent. Deborah S. Kelley, an oceanographer at the University
of Washington, and her team announced this spectacular
find in March 2005. The group had discovered the area, which they named Lost
City, in 2000. It lies about 2500 kilometers west
of Bermuda. They returned in 2003 to explore the unusual underwater formations. Heated
water spews from vents that dot the area. Chemical reactions deposit calcium
carbonate at the surface of the vents. The deposits form white chimneys, mounds,
and spires. One chimney is 18 stories tall. The white chimneys and other structures proved to be very different from
the more well-known black smokers. Black smokers are thermal vents that exist
in much hotter (400 ˚C), acidic water near mid-ocean ridges. The white
chimneys are highly alkaline and form in cooler water (66–76 degrees Celsius).
Black smokers get their energy from molten rock emerging from seafloor spreading.
The energy fueling the white chimneys comes from chemical reactions in the
rock formations. Black smokers are known for the complex and sometimes very large organisms
that live nearby. These creatures have evolved to take advantage of the high
temperatures and acidic waters of the area. Kelley's team first assumed they
would not find much evidence of life in the highly alkaline environment of
the white chimneys. The water there is about as caustic as drain cleaner. Using a high-tech underwater vacuum, Kelley’s team collected a variety of
crustaceans from the surface of the chimneys. Crabs and shrimps − mostly
translucent or transparent, and less than 1.3 centimeters long − abounded
in the crevices of the chimneys. Perhaps more remarkable was the team's discovery of legions of chemoautotrophic
microbes living inside the chimneys. The microbes obtain energy by oxidizing
hydrogen or methane. In contrast, microbes living inside black smokers synthesize
carbon dioxide, hydrogen sulfide, and metals—all of which are absent in white
chimneys. Scientists speculate that the conditions in the white chimneys might be similar
to conditions that existed when life emerged on Earth. Further study could
reveal information about the origins of life and could even help scientists
recognize signs of life on other planets. Sources: http://www.sciencedaily.com/releases/2005/03/050307215036.htm http://www.sciencenews.org/articles/20010714/fob3.asp
(original discovery) http://www.msnbc.msn.com/id/7079981/ |