Posted on 02/03/2005 12:21:09 PM PST by 68skylark
WASHINGTON (AP) - Tiny single-celled organisms, many of them previously unknown, have been discovered beneath nearly seven miles of water in the deepest part of the ocean.
A sample of sediment collected from the Challenger Deep southwest of Guam in the Pacific Ocean Islands yielded several hundred foraminifera, a type of plankton that is usually abundant near the ocean surface.
"On the species level, all the species we found from the Challenger Deep are quite new," researcher Hiroshi Kitazato said vie e-mail.
The outer shapes are similar to other known foraminifera, but details of their structure differ, explained Kitazato, of the Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology.
"I am very surprised that so many very simple, soft-shelled foraminifera are dwelling at the deepest point of the world ocean," he added.
"It is also exiting that most of the group belong to the oldest branch of foraminifera," he added, suggesting that these deep locations may form some sort of refuge for them.
These distinct creatures probably represent the remnants of a deep-dwelling group that was able to adapt to the high pressures, the researchers suggest in reporting the find. Their discovery is reported in this week's issue of the journal Science.
Because the water is so deep, the pressure where the find was made is 1,100 times more than normal atmospheric pressure at the surface.
While many foraminifera have hard shells, the researchers noted that this newly found group does not.
Similar, though not identical, groups have been found in other, slightly shallower, ocean trenches, they note.
The creatures probably can exist by ingesting particles of organic matter that drift down from above or materials that are dissolved in the seawater, Kitazato said.
The research was funded by the Japan Agency for Marine-Earth Science and Technology, the Japan Society for Promotion of Science, the Kaplan Foundation and the Natural Environment Research Council.
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On the Net:
Science: http://www.sciencemag.org
Japan Agency for Marine Earth Science and Technology: http://www.jamstec.go.jp
Talk about deep thoughts.
Abyssians??
..nothing has been shown, that he still isn't. IMHO, These Organisms are still a much higher (on many levels) lifeform than many (if not all) Washington D.C. Liberals. :^)
Thanks.. :^)
Don't feel bad, you're in good company. I'm going to go genuflect or something now.
I did not have sex with that sea canyon, the Merianas trench.
I wonder how far down a full beer can would make it before being crushed like a bug?
"We were talking, a day or so ago, about "new" phyla. This is the sort of thing I was thinking about. (Whether this is a good example or not, I haven't a clue.) It could be happening, or be on the verge of happening, almost all the time. It's difficult to know except after millions of years of hindsight."
As a bugologist, IMHO, these are more likely an old group, just newly discovered, especially since the authors said they were related to the oldest branch of the forams.
"They can dig a sea-floor core and look for older specimens. They might be fossilized. (I'm not sure if fossils of such animals are possible, and I'm not sure they can operate a dig that deep.)"
A sea floor core is technically possibly, but very difficult at that depth. The bugs are "soft shelled", so a fossil is possible, but highly unlikely. Think of a foram as a single celled snail. Hard shelled forams are very common fossils.
Seems likely. I was just using this as an example. A new body type could pop up. In a crowded world it would have a tough time, and it would take forever for it -- and its ever-varying progeny -- to be recognized as a new phylum. The whole conjecture was in response to a question about "why don't we see new phyla"?
"The whole conjecture was in response to a question about "why don't we see new phyla"?"
I think the answer is simply that we have too short a time frame (say a couple hundred years since people have really been looking - not enough time for anything to happen from an evolution point of view, except extinction).
The forams form one of the best cases for "punctuated equilibrium". There's a 10 million year stretch of great fossil data from the late miocene to the present.
(Malmgren, B.A., W.A. Berggren and G.P. Lohmann. 1983. Evidence for punctuated gradualism in the Late Neocene Globorotalia tumida lineage of Planktonic Foraminifera. Paleobiology 9:377-89.
I've heard that even extracting and preserving the top samples from that depth is quite difficult.
Perhaps the fossil record doesn't reflect that these are the oldest creatures, but rather the deepest creatures. That would account for them being at the lowest levels.
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