Posted on 02/03/2004 2:37:14 PM PST by AdmSmith
The mystery of where Earth's first snakes lived as they were evolving into limbless creatures from their lizard ancestors has intrigued scientists for centuries. Now, the first study ever to analyze genes from all the living families of lizards has revealed that snakes made their debut on the land, not in the ocean. The discovery resolves a long-smoldering debate among biologists about whether snakes had a terrestrial or a marine origin roughly 150 million years ago--a debate rekindled recently by controversial research in favor of the marine hypothesis.
In a paper to be published in the 7 May 2004 issue of the Royal Society journal Biology Letters, Nicolas Vidal, a postdoctoral fellow, and S. Blair Hedges, a professor of biology at Penn State, describe how they put the two theories to the test. They collected the largest genetic data set for snakes and lizards ever used to address this question. Their collection includes two genes from 64 species representing all 19 families of living lizards and 17 of the 25 families of living snakes.
Genetic material from some of the lizards was difficult to obtain because some species live only on certain small islands or in remote parts of the world. "We felt it was important to analyze genes from all the lizard groups because almost every lizard family has been suggested as being the one most closely related to snakes. If we had failed to include genes from even one of the lizard families, we could have missed getting the right answer," Hedges explains.
"For the marine hypothesis to be correct, snakes must be the closest relative of the only lizards known to have lived in the ocean when snakes evolved--the giant, extinct mosasaur lizards," Vidal says. "While we can't analyze the genes of the extinct mosasaurs, we can use the genes of their closest living cousins, monitor lizards like the giant Komodo Dragon," he explains.
The team analyzed gene sequences from each of the species, using several statistical methods to determine how the species are related. "Although these genes have the same function in each species--and so, by definition, are the same gene--their structure in each species is slightly different because of mutations that have developed over time," Vidal explains. When the genetic comparisons were complete, Vidal and Hedges had a family tree showing the relationships of the species.
"Our results show clearly that snakes are not closely related to monitor lizards like the giant Komodo Dragon, which are the closest living relatives of the mosasaurs--the only known marine lizard living at the time that snakes evolved," Vidal says. "Because all the other lizards at that time lived on the land, our study provides strong evidence that snakes evolved on the land, not in the ocean."
The research suggests an answer to another long-debated question: why snakes lost their limbs. Their land-based lifestyle, including burrowing underground at least some of the time, may be the reason. "Having limbs is a real problem if you need to fit through small openings underground, as anybody who has tried exploring in caves knows," Hedges says. "Your body could fit through much smaller openings if you did not have the wide shoulders and pelvis that support your limbs." The researchers note that the burrowing lifestyle of many other species, including legless lizards, is correlated with the complete loss of limbs or the evolution of very small limbs.
This research was supported by the National Aeronautics and Space Administration Astrobiology Institute and the National Science Foundation.
(Excerpt) Read more at science.psu.edu ...
Coincdental or not, you agree they eat dust and therefore the literal passage is true.
The Biblical writer was merely describing what people of the time thought, not biological facts. Are snakes wise??
My ex-wife was't very wise, but then again..
Now, that is about the most convoluted explanation I've seen yet. Are you saying that a verse can be interpreted figuratively or literally, depending on the reader?
Metaphors are clearly indicated in the Bible....period!!!! If not otherwise indicated, God's word is to be taken literally. That's the way it works, no matter who the reader may be.
You may feel better by finding ways to explain that which is difficult or impossible for us to understand, but you are second guessing God. Not a good idea, IMO.
Like the definitions of "sex" and "is", the definition of "eat" is subject to endless interpretation. Normal people interpret the word "eat" to mean ingest for nourishment. Are you suggestion that the Bible was written by Bill Clinton?
Let me ask you. Do snakes prosper and have success ?
Where do you get that ? In fact the opposite is true. God created the land animals and saw that it was good.
I'm saying that it remains true regardless who reads it.
Metaphors are clearly indicated in the Bible....period!!!! If not otherwise indicated, God's word is to be taken literally. That's the way it works, no matter who the reader may be.
Logically, that is a false conclusion. If God refelcts truth in nature and if in nature an analogy can be both true literally and metaphorically then scripture should be able to be both literally true and metaphorically true at the same time. To assume that every scripture verse must be one or the other and not possibly be both is illogical.
You may feel better by finding ways to explain that which is difficult or impossible for us to understand, but you are second guessing God. Not a good idea, IMO.
I'm not guessing God. I'm holding out the prospect that for every verse written the well of knowledge of God is potentially endless. For me to box his scripture into an either/or sorting mechanism is to place more restrictions on hiw writting than we place on Steven King.
So, you believe that after this was written no one happened to notice that a snake ate the occasional frog ? Do you really believe the Hebrew people were that dumb ? Of course they knew that snakes ate other things.
Now your getting it.
Everyone is missing the point here.
Why are we spending hard-earned taxpayer money on this nonsense?
If somebody wants to do this kind of research, fine. But let them get private funds or pay for it out of their own pocket. Don't make us pay for it!
Sorry, the Bible is not multiple choice where more than one answer is correct.
I'm sure you will come up with some silly explanation to this question but I'll ask anyway. What would be the purpose in leaving the Bible open to any ol' interpretation that someone thinks he can justify?
What if someone decided to interpret the resurrection of Christ as some type of symbolic language? After all, we cannot explain it in our limited understanding, can we?
If your liberal translation method was applied, the Bible could say just about anything you want it to. In fact that is precisely how cults are born.
Now that is a key point. Every kind of creature is adapted for its environment right now. There are no higher or lower organisms.
As for snakes being judged wise because they are successful -- that's pure clintonism.
That's the very definition of clintonian: finding an obscure definition of a word that makes your statement true, even though no one would ever suspect that definition in its original context.
There's a word for this, but my vocabulary fails me this morning. It means deliberately using a word in a way that is literally true, but deceitful in its effect on the listener.
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