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Scientists Discover Where Snakes Lived When They Evolved into Limbless Creatures
Penn State ^ | 30 January 2004 | press release

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 ...


TOPICS: Culture/Society; Extended News
KEYWORDS: crevolist; evolution; science
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To: AdmSmith
I thought this was an article about the U.S. Senate. Oh Well, moving on...
121 posted on 02/04/2004 8:19:49 AM PST by PsyOp (Note to Jihadists: I profile and carry a gun.)
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To: Southflanknorthpawsis
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?

I didn't say that at all. What I said is that a passage can be true in both a literal sense and a metaphorical sense. You have concluded that its not possible for it to be true at the same time for both. I disagree.

122 posted on 02/04/2004 8:24:25 AM PST by VRWC_minion (Opinions posted on Free Republic are those of the individual posters and most are right)
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To: js1138
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.

As a metaphor, snakes are wise and were apparently recognized as such by the Hebrews who used one of the meanings of wise as being successful. If there was no literal connection then the metaphor would have fallen on deaf ears. The metaphor only works in this case if the literal is somehow true to the listener. Or do you think the Hebrew people were being taught by Jesus that snakes had some mystical power of wisdom ?

123 posted on 02/04/2004 8:30:34 AM PST by VRWC_minion (Opinions posted on Free Republic are those of the individual posters and most are right)
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To: VRWC_minion
Their theology may have been on the mark, but their biology leaves a little to be desired.

Ancients frequently used verbal nouns (gerunds) or adjectives as proper nouns.

One of the Greek words for snake is actually "draco", which means literally "the staring one," or "one who stares", since snakes have no eyelids - from a vereb meaning to stare.
124 posted on 02/04/2004 8:37:32 AM PST by ZULU (GOD BLESS SENATOR JOE MCCARTHY!!!)
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To: VRWC_minion
To use a very worn out phrase.... You can't have it both ways. You can disagree because it works for settling it in your mind, but it doesn't make it right.

I trust God's methods over man's.

Thank you.

125 posted on 02/04/2004 8:37:58 AM PST by Southflanknorthpawsis
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To: FourtySeven
I tried it myself a few years ago, and no matter how you go, one way or the other, a particular verse will be EITHER literal OR metaphorical. There simply isn't any way to get blood from that stone.

I agree. But as you can see there are two groups who believe that such a choice MUST be made for every single verse. To that I disagree because logic provides that A&B can be true, that A&B can be false and that either A&B can be true. Further, just because I do not currently see a literal truth in a metaphor or a metaphor in a literal truth doesn't mean I have considered all possibilites. I often come back to verse that reveals itself in new ways.

I had this experience in several verses. One in a verse that seems to contracdict PI, which literally proves out that it doesn't and another in the mustard seed that literally seems to say its the smallest seed which literally it doesn't. When one takes a closer "more literal" reading of those its becomes obvious (at least to me) that they are literally true.

The mustard seed story is a good one for the literalist that shows how Jesus taught from the literally true to the metaphorically true. Both levels work at the same time.

126 posted on 02/04/2004 8:40:11 AM PST by VRWC_minion (Opinions posted on Free Republic are those of the individual posters and most are right)
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To: Southflanknorthpawsis
I trust God's methods over man's. Thank you.

Good, then Jesus used literal truths to make metaphors.

127 posted on 02/04/2004 8:41:47 AM PST by VRWC_minion (Opinions posted on Free Republic are those of the individual posters and most are right)
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To: VRWC_minion
Or do you think the Hebrew people were being taught by Jesus that snakes had some mystical power of wisdom ?

I think that people then and now believe certain animals have mystical powers. We "modern" people would not admit this out loud, but there are innate reactions to the appearance and behavior of various animals that have made Disney rich. I bet I could find people living right now who believe snakes have mystical wisdom in the usual sense of the word.

But based on your equation of successful=wise, all living things are wise and the meaning is diluted to nothing. There is no such thing as a type of living organism that is not successful.

128 posted on 02/04/2004 8:43:38 AM PST by js1138
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To: ZULU
Their theology may have been on the mark, but their biology leaves a little to be desired.

According to God, their theology was totally flawed when left to their own devices. That is why its called revelation. If God revealed himself using stories then it only makes sense that the stories have a basis in fact, seeing that he was there and all.

129 posted on 02/04/2004 8:44:28 AM PST by VRWC_minion (Opinions posted on Free Republic are those of the individual posters and most are right)
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To: js1138
But based on your equation of successful=wise, all living things are wise and the meaning is diluted to nothing. There is no such thing as a type of living organism that is not successful

Dodo bird ?

130 posted on 02/04/2004 8:54:44 AM PST by VRWC_minion (Opinions posted on Free Republic are those of the individual posters and most are right)
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To: VRWC_minion
I didn't know dodo's were still alive. I suppose if the earth is hit by a big enough comet, we will all fail to survive and all fail to be wise.

What is your point? Obviously any creature can be exterminated, except possibly cockroaches. Does that make roaches wise?

131 posted on 02/04/2004 8:58:55 AM PST by js1138
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To: Southflanknorthpawsis
"I see, Zulu. Because you like snakes, you find a need to interpret Scripture to suit your personal likes. Hmmmmm!!!!!"

No, I think what I am doing is looking at a passage in the Bible, trying to figure out what the meaning of the passage is from a moral perspective, and then relate that passage to known biological facts.

"How you translate that fact into denial of the events leading to the fall of man is confusing to me."

The way I interpret it is, Satan took the form of a serpent and tempted Eve to disobey God. She got Adam involved, and God caught them at it. He punished Adam and Eve and their descendents, cursed Satan, and promised to send a redeemer to save them from their sins.

I think that's the essence of the story.

I don't think we need to accept verbatim the nitty gritty of every detail. But then, that's just my opinion.

At any rate, I know snakes evolved from lizards who had legs. I know this happened far in the distant past, in the Mesozoic era, before modern mammals had evolved. I know that therefore, God could not have "punished" snakes by taking their legs away for tempting Adam and Eve and "snakes" didn't tempt them anyway. The tempter was actually Satan. God really cursed Satan and promised He would send a Savior through a woman ( Mary ) who would crush him.

132 posted on 02/04/2004 8:59:13 AM PST by ZULU (GOD BLESS SENATOR JOE MCCARTHY!!!)
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To: VRWC_minion
Here's some info just so we all know what kind of snakes we're talking about:

http://www.vaherper.com/pages/mesnakes.htm

Lost in all this dust eating, Adam falling, "Are snakes wise" silliness is...

How did the Serpent talk? Snakes certainly aren't equipped with the morphology to facilitate speech. Did they lose this ability with the fall of man too? Or, is this (YET ANOTHER) not really literal but still literal biblical story?
133 posted on 02/04/2004 8:59:43 AM PST by whattajoke (Neutiquam erro.)
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To: VRWC_minion
"They were capable of holding multiple meanings as being true at the same time. Even the names of the characters in the bible demonstrate this."

Can't argue with that. Adam means "man" dosen't it?
134 posted on 02/04/2004 9:00:37 AM PST by ZULU (GOD BLESS SENATOR JOE MCCARTHY!!!)
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To: VRWC_minion
"it only makes sense that the stories have a basis in fact, "

I don't dispute that the stories had a basis in fact, but that doesn't necessarily mean the stories were meant to be taken entirely in a literal sense which is what a lot of Christian fundamentalists believe.
135 posted on 02/04/2004 9:02:59 AM PST by ZULU (GOD BLESS SENATOR JOE MCCARTHY!!!)
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To: VRWC_minion
The mustard seed story is a good one for the literalist that shows how Jesus taught from the literally true to the metaphorically true. Both levels work at the same time.

I've come to similar conclusions. Basically, it's how the person reads it, and how the message contained therein best brings them closer to God. Since people are different, it's not suprising people will be brought to God in different ways. (Not saying that there aren't SOME absolutes in the Bible of course, but they aren't as plentiful as others would have us believe, imo)

136 posted on 02/04/2004 9:04:14 AM PST by FourtySeven (47)
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To: whattajoke
How did the Serpent talk? Snakes certainly aren't equipped with the morphology to facilitate speech. Did they lose this ability with the fall of man too? Or, is this (YET ANOTHER) not really literal but still literal biblical story?

;^)

137 posted on 02/04/2004 9:04:54 AM PST by js1138
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To: ZULU
At any rate, I know snakes evolved from lizards who had legs. I know this happened far in the distant past, in the Mesozoic era, before modern mammals had evolved. I know that therefore, God could not have "punished" snakes by taking their legs away for tempting Adam and Eve and "snakes" didn't tempt them anyway.

You are, in essence, calling God's word a lie or a fairy tale.

If you believe you are a Christian and still deny His truth, I think you need some prayerful time with your Bible. Something is very wrong with this picture.

138 posted on 02/04/2004 9:09:37 AM PST by Southflanknorthpawsis
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To: ZULU; VRWC_minion
(adapted from An Urgent Plea to Pastors by Doug Phillips, J.D. in Back to Genesis, No.119, p.c.)

It is a dangerous thing for someone to say that the Bible is just 'subjective' or 'allegorical' when the plain meaning of the writers is literal as it is if a father warns his son of a dangerous snake but is just joking. The moment you undermine the authority of the Bible as God's Word you undermine faith and the possibility of learning to trust in the Creator, when the fact of the matter is that the Creator and His Word are utterly trustworthy.

And whilst it is true that some parts of the Bible are allegorical and poetic, the context will clearly indicate that it is so. If I compare my sweetheart to a tropical dawn everybody knows I am not being literal, but if I say that I am going to meet her at the bus stop at noon the following day she knows I am being literal. It is only the proponents of false religion who wish you to believe that the Bible is not to be taken literally or convince you that matter and pain are illusiory.

139 posted on 02/04/2004 9:28:54 AM PST by Southflanknorthpawsis
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To: ZULU
Pardon me while I put on my "Christian fundamentalist" hat.......

As a Christian, Zulu, how do you determine what is literal and what is not?

Are all things that are impossible for man (but not God) explained away by your interpretations?

Out of curisosity, I'd like to ask your interpretation of just a few things, though there are many more:

1) The Resurrection
2) Walking on water
3) Immaculate conception
4) Water to wine
5) Multiplying the bread and fish

These are only a few things that defy logic for man, yet we are told (and I believe) they indeed happened.

140 posted on 02/04/2004 9:46:16 AM PST by Southflanknorthpawsis
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