Posted on 12/17/2002 3:45:31 AM PST by Junior
WASHINGTON - Researchers have sequenced the gene structure of the sea squirt, a homely creature of the ocean bottom that has intrigued scientists since the days of ancient Greece.
In a report appearing Friday in the journal Science, 87 scientists from five countries announced they have correctly assembled the 150 million DNA base pairs of the sea squirt genome. The humble creature is the seventh animal to be genetically sequenced.
Mike Levine, a researcher at the University of California, Berkeley, and a co-author of the study, said studying the genetics of the sea squirt gives a glimpse at the very early history of evolution, a time more than 550 million years ago when animals with backbones were just beginning the shift toward a new age of complexity.
"The sea squirt enjoys a special place in the hearts of biologists because it provides the first evolutionary connection between invertebrates and vertebrates," Levine said. "You look at the adult and you think it is one simple creature, but if you look at the embryo, you see a clear connection to higher animals. This is our ancient, ancient cousin."
Adult sea squirts live fixed on the bottom in shallow ocean waters. The sea squirt has a rubbery, hollow body. Vents suck in seawater and shoot it out after filtering nutrients. It is this squirt of water that gives the animal its name.
Aristotle, the ancient Greek philosopher, studied the sea squirt and classified it as a mollusk. That stuck until the 1870s, when a Russian biologist recognized that the embryo of the sea squirt closely resembled a tadpole, with a head, tail and central nerve bundle called a notochord. It was this discovery that led scientists to understand that the sea squirt was actually a chordate, a member of the same animal phylum as humans.
"They're related to us," Levine said. "Charles Darwin called them our ancient relatives because they had a common ancestor with humans."
Studies showed that embryonic humans shared the same notochord structure as the embryo of the sea squirt. In humans, the structure goes on to become the central nervous system. In the sea squirt, the tadpole-like creature finds a place to grasp on the ocean floor and transforms into the tube-like adult.
The other animals to be genetically sequenced are human, mosquito, mouse, nematode, fruit fly and puffer fish. All but the human and mosquito are important laboratory research animals.
Levine said the sea squirt has 15,000 to 16,000 genes, about half of the number estimated for the human. The animals has about 150 million DNA base pairs, a fraction of the 3 billion found in humans.
The sea squirt is simple to manipulate and study in the lab. Levine said that the animals shares many of the same genes as humans and that studying the sea squirt researchers should be able to gain new understanding about how genes interact and regulated.
He had better check his sources.
If you evolutionists had a brain you would realize that this squirt has no ancestors and no descendants. That disproves evolution.
Unlike what you and your fellow evolutionists think, this discussion is about facts, not about the messengers of the facts.The article here as has been shown disproves evolution. What that means is that God is not dead, that materialistic evolution is bunk.
As usual you try to attack me by misrepresenting what I have said on other threads. You had an opportunity to discuss it there but of course since people would have seen the context there and my statements were correct you did not do so then. Let's see you give the full response I gave and a link to the thread where it was said. You will not of course because you will be proving that you have misrepresented my statements.
And the fact is, not all discoveries in genetics falsify evolution, which is what you always claim. Now, you've been caught out, and I'd like to hear you admit you were wrong. Of course, that'll never happen, as you'll forget this exchange ever took place, as you've forgotten every exchange where you had your tail-end handed to you on a silver platter. Have you figured out that chimps don't have tails yet? Of course, you've forgotten making that remark as it occured two days ago. Just like you forgot about claiming circles were not ellipses, or that the planets had wildly-elliptical orbits, or that 1720 is a really big number. Your credibility on anything is completely shot, but you don't remember this as your memory resets to zero on each new thread.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.