Fossil Shows Fish Evolving Surf-To-Turf
Skull, Shoulders And Pelvis Found Of Most Primitive 4-Legged Creature In History
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Photo
This undated artist's rendering provided by Philip Renne shows a Ventastega. Scientists have found the fossil skull of the most primitive four-legged critter in Earth's history, a key point in the evolution from fish to animals that eventually walked on on land. (AP Photo/Philip Renne)
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The 365 million-year-old fossil skull, shoulders and part of the pelvis of the water-dweller, Ventastega curonica, were found in Latvia, researchers report in a study published in Thursday's issue of the journal Nature.
Even though Ventastega is likely an evolutionary dead-end, the finding sheds new details on the evolutionary transition from fish to tetrapods. Tetrapods are animals with four limbs and include such descendants as amphibians, birds and mammals.
While an earlier discovery found a slightly older animal that was more fish than tetrapod, Ventastega is more tetrapod than fish. The fierce-looking creature probably swam through shallow brackish waters, measured about three or four feet long and ate other fish. It likely had stubby limbs with an unknown number of digits, scientists said.
"If you saw it from a distance, it would look like a small alligator, but if you look closer you would find a fin in the back," said lead author Per Ahlberg, a professor of evolutionary biology at Uppsala University in Sweden. "I imagine this is an animal that could haul itself over sand banks without any difficulty. Maybe it's poking around in semi-tidal creeks picking up fish that got stranded."
This all happened more than 100 million years before the first dinosaurs roamed Earth.
Scientists don't think four-legged creatures are directly evolved from Ventastega. It's more likely that in the family tree of tetrapods, Ventastega is an offshoot branch that eventually died off, not leading to the animals we now know, Ahlberg said.
"At the time there were a lot of creatures around of varying degrees of advancement," Ahlberg said. They all seem to have similar characteristics, so Ventastega's find is helpful for evolutionary biologists.
Ventastega is the most primitive of these transition animals, but there are older ones that are oddly more advanced, said Neil Shubin, professor of biology and anatomy at the University of Chicago, who was not part of the discovery team but helped find Tiktaalik, the fish that was one step earlier in evolution.
"It's sort of out of sequence in timing," Shubin said of Ventastega.
Ahlberg didn't find the legs or toes of Ventastega, but was able to deduce that it was four-limbed because key parts of its pelvis and its shoulders were found. From the shape of those structures, scientists were able to conclude that limbs, not fins were attached to Ventastega.
One question that scientists are trying to figure out is why fish started to develop what would later become legs.
Edward Daeschler, associate curator of vertebrate zoology at the Academy of Natural Sciences in Philadelphia, theorizes that the water was so shallow that critters like Ventastega had an evolutionary advantage by walking instead of swimming.
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See all 149 CommentsStrange how the bible says that in the beginning, there was 6 days of creating creatures and man. There is never any mention of dinosaurs. Hhmmmmmm. Oh, now I know why - the bible was written by man (the first 5 books by Moses I understand) who at the time had no knowledge of ancient creatures. So for those who believe that the bible is the definitive word on our past, you need to realize something. The bible was written by early priests and scribes, and altered by the Catholic Church many times, to teach sometimes frightening lessons. Some of the stories are based partly on true events, while others are purely fictional.
Congrats on finding this slimey lizard. Hope his bones turn to crude soon to help the oil crisis.
And it turned out to be a neocon.
Posted by ndg1979 at 04:50 AM : Jun 26, 2008
Hello there....this isn''t a debate on the Bible but you noticed that there are some interesting things in it that are a little hard to explain. For instance: In Isiah it says: "It is he that sitteth upon the circle of the earth". How did Isiah know that the world was round? Job also says "He sealeth up the hand of every man; that all men may know his work." How did Job know that every man had a unique fingerprint? Or have you ever read some of the Levitical laws of health and sanitation? Like washing under running water (doctors spead disease from one patient to another until this was discovered). Or how a child was to be circumcised on the 8th day of it''s life. We know now that the 8th day of a child''s life is when they begin to produce vitamin K which causes the blood to clot. There are hundreds of mysteries like this in the Bible. Even if you don''t believe in the Bible you have to admit these things are pretty amazing.
You''re waisting the effort it takes to type hon. Religion is opinion, hence, hard to argue. Science is provable and reproducable fact. Those so enveloped in their religion that they refuse to see fact are entitled to their opinion and usually cannot be swayed. Waiste of effort.
Posted by nopacifism2
Your faith, and everybody else''s is also a hypothesis, not a fact.
A lot of my ancestors swung from trees...it wasn''t because they were monkeys, it was because they were horse theives! :)
http://dictionary.reference.com/browse/man
there''s your defintion and it doesn''t mention the "bib"le anywhere
Although spoken language is believed to have developed tens of thousands of years ago, the written word emerged much later, as hunter-gatherers developed more permanent agrarian societies.
Some 9,000 years ago, the Sumerians invented counting tokens. These simple stamps were inscribed with pictures that represented the objects to be itemized.
They could be impressed in clay to document a record of land, grain, or cattle ownership.
These pictographs became more stylized as scribes began drawing them with a wedge-shaped stylus made of reeds.
This script is now known as cuneiform, our first written language.
The next step occurred in Egypt, sometime toward the end of the fourth millennium B.C.
Unlike cuneiform, which depicted individual objects, hieroglyphics represented sounds.
This major advance, called a %u201Cone-sign, one-sound%u201D system of writing, is regarded as the first alphabet.
Language developed elsewhere, too.
Cultures with no apparent connection to the Near East -- in China, the Indus valley, and much later, the Olmecs and Mayans of Mesoamerica -- developed their own advanced alphabets.
Whether these arose independently or were influenced by existing languages is still a matter of fierce debate among scholars.
Posted by nopacifism2
How is that a fact? Where is your proof? Your bible is only a theory, like the rest of them.
Posted by faith_in_w
Were you there? Did you actually hear that? Where''s the recording? Is it carved in stone? Because the written word has changed so much to conform people to the times at hand, written word is not worth the paper it has been printed on. Just go through all the reiterations of the bible...unless you burned them because a new edition was printed.
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Posted by faith_in_w at 09:45 AM
Prove it.
BTW - the craziest notion I''ve heard yet about the bible being the source of the words man and woman. The old testament was written around 3 - 2,000 yrs BC by best estimates. The scholars were aware of the presence of males and females by this time and had words or signs for man and woman and used them in the story of Adam and Eve. The words man and woman per se are derived from the Anglo-Saxon language spoken in western Europe in the 4th and 5th centuries AD. The first English translations of the bible date from around the 7th century, thus they would contain the trems man and woman.
As for the bible-literalism wackos - you are better off just to ignore them, they have nothing meaningful to add to any scholarly scientific discussion because they are most definitely not scientists. It''s amazing how they feel somehow empowered to hold forth on fields they know little or nothing about. It''s like going in and arguing with a cardiac surgeon about medicine when their only credentials are those of a garbage man. They just reinforce proof of the arcane nature of their obsolete beliefs and their intellectual bankruptcy.
posted by nopacifism2
No, that was natural selection.
Posted by USBrit
Sorry Brit, I can''t by into that being that I believe in creation and believe that the Creator gave us the sciences of geology, minerology, astronomy, palaentology, biology and zoology, as well as ALL of chemistry and physics.
pre7his7toric (pr%u0113%u2032his ttr%u2032ik)
adjective
of the period before RECORDED history
Learn to use a dictionary.
You just refuse to admit this.
Posted by nopacifism2
No, it just means that ceolocanths had been hanging out round Mauritius for millions of years and no-one had found one.
WRONG!
You are wrong. I believe that if you read your Bible Genesis 1:20-27 you will find that God first created the creatures of the sea and the fowl of the air a "day" before he created humans.
The "fact" that man came before the animals is the misconception of many biblical believers and their teachers who have not really read The Bible for themselves, but rather, choose to regurgitate what others have "taught" them about what is in The Bible.
Read The Bible, please. Read whether you are a Christian, Agnostic, or Atheist.
There are many spiritual teachings in there that benefit all humanbeings. There are many things that My Lord and Saviou, Jesus Christs, talks about that many Christians are missing even today.
Must be our modern Global Cooling that killed most of the off...
;)
Posted by checkthepast
Why would he do that in a way that can be so easily (in your opinion) misunderstood by vast numbers of the finest minds ever produced by human kind to show that life evolved (and the universe is 13.6 billion years old, not 6000) rather than being created by him? Seems like a lot of trouble for God to go through just to pull a fast one on the human race.
Your problem is you think humans have all the answers. But only God does. Not humans.
Posted by nopacifism2 at 10:15 AM : Jun 26, 2008
And I was pointing out to you that to call something ''historic'' and denying the appropriate use of the word ''prehistoric'' shows that you have an appallingly shallow intellect.
Brit,
Please don''t voice ''my opinion''..where do you get the idea that I was talking about what was in ''my opinion to be "vast numbers of the finest minds ever produced by human kind". You have a right to your opinion as well as anyone just please don''t make statements and attempt to qualify them as someone elses opinion.
Thanks
;)
Posted by checkthepast
You pass the test - I wondered who''d pick up on that. Yes, the oceans were warmer for times, and colder at times and vastly different shapes (due to continental drift) over their billions years of existence.
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