Scientists Discover Where Snakes Lived When They Evolved into Limbless Creatures

Penn State ^ | 30 January 2004 | press release

[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.

[cyborg]

LOL!

[ErnBatavia]

[cyborg]

omg...

[Modernman]

Because thou hast done this, thou art cursed above all cattle, and above every beast of the field

I wouldn't call snakes cursed. They're very effective predators, good at what they do. Also, science seems to be discovering some very interesting uses for the chemicals that they produce.

Snakes have gotten a bum rap.

[VRWC_minion]

That snakes eat dust?

Everyone knows snakes rinse their food thoroughly before eating.

[shaggy eel]

Straight out of Dr. Bukks

,,, and it recently picked up a $60k pay rise, so now there's no excuse to not put that ivory right.

[aruanan]

"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.

Picture thinking.

[Oztrich Boy]

I have never held a snake in my life and don't plan to

Then you're going to heck. The Bible commands that you handle serpents.

[VRWC_minion]

Snakes have gotten a bum rap.

I agree.Its bad enough to have to swallow your food whole. Getting stepped on must be a real bummer when going about your own business.

[Ol' Sparky]

"Given that evolution, according to Darwin, was in a continual state of motion ...it followed logically that the fossil record should be rife with examples of transitional forms leading from the less to more evolved. ...Instead of filling the gaps in the fossil record with so-called missing links, most paleontologists found themselves facing a situation in which there were only gaps in the fossil record, with no evidence of transformational intermediates between documented fossil species." (Schwartz, Jeffrey H., Sudden Origins, 1999, p. 89.)

[VRWC_minion]

Matthew 10:16
Behold, I send you forth as sheep in the midst of wolves: be ye therefore wise as serpents, and harmless as doves.
(Whole Chapter: Matthew 10 In context: Matthew 10:15-17)

Matthew 23:33
Ye serpents, ye generation of vipers, how can ye escape the damnation of hell?
(Whole Chapter: Matthew 23 In context: Matthew 23:32-34)

Mark 16:18
They shall take up serpents; and if they drink any deadly thing, it shall not hurt them; they shall lay hands on the sick, and they shall recover.
(Whole Chapter: Mark 16 In context: Mark 16:17-19)

Luke 10:19
Behold, I give unto you power to tread on serpents and scorpions, and over all the power of the enemy: and nothing shall by any means hurt you.
(Whole Chapter: Luke 10 In context: Luke 10:18-20)

1 Corinthians 10:9
Neither let us tempt Christ, as some of them also tempted, and were destroyed of serpents.
(Whole Chapter: 1 Corinthians 10 In context: 1 Corinthians 10:8-10)

James 3:7
For every kind of beasts, and of birds, and of serpents, and of things in the sea, is tamed, and hath been tamed of mankind:
(Whole Chapter: James 3 In context: James 3:6-8)

Revelation 9:19
For their power is in their mouth, and in their tails: for their tails were like unto serpents, and had heads, and with them they do hurt.
(Whole Chapter: Revelation 9 In context: Revelation 9:18-20)

[Southflanknorthpawsis]

One could argue that the serpent in Genesis is not a snake but rather a representation of evil

One could argue, but one would be wrong. When stated clearly as literal in the Bible, we are to interpret literally, as in the case of the serpent's curse.

[FreedomCalls]

I've been looking for that picture or one like it. Thanks.

[Southflanknorthpawsis]

The Bible commands that you handle serpents.

Aha....but the same Bible promises me forgiveness, so I'm okay. ; *)

[VRWC_minion]

If the very next verse is certainly a metaphor, as follows

15 And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel,

How are you so certain the preceeding verse refers to a snake ? In fact many if not most believe that the serpent is a fallen Angel sometimes called Satan.

[protest1]

Yes, snakes do eat dust.

by Carl Wieland

First published in:
Creation Ex Nihilo 10(4):38,
September–November, 1988

In Genesis 3:14 we read, 'And the Lord God said unto the serpent... "upon your belly you shall go, and shall eat dust all the days of your life".' Since snakes do not really appear to eat dust, this has been taken as an example of either obvious metaphor (which seems reasonable) or an example of the Bible's propensity to error, depending upon one's bias.
In Micah 7:17 we read, '(The nations) shall lick the dust like a serpent'.

Once again we have the situation where, as more information has come to light, the Bible has been shown to be not only accurate, but accurate in minute detail. Snakes do deliberately and purposely eat and lick dust.

There is an organ in the roof of a snake's mouth called 'Jacobson's organ'. This helps the snake to smell in addition to its nose. Its darting, forked tongue samples bits of dust by picking them up on the points of the fork, which it then presents to its matching pair of sensory organs inside its mouth. Once it has 'smelt' them in this way, the tongue must be cleaned so the process can be repeated immediately.

http://www.answersingenesis.org/docs/1295.asp

[Southflanknorthpawsis]

You know, Minnie...I should have known you'd turn this into an argument. No thanks, I think I'll pass.

[VRWC_minion]

Its not meant to be an argument. I maintain that most scripture is meant to be simultaneously understood on several levels, literal and metaphorical being two of them. To accomplish this they are not entirely satisfactorily read on either level. Knowing that atheists love to pick apart scripture like apes picking knats, I hedged the literal.

[VRWC_minion]

On the metaphorical sense, the text discuss eating from the tree of knowledge and the tree of life. Satan is being told he cannot eat from these trees and is condemned to eating dust. Dust is a symbol for death as in ashes to ashes, dust to dust.

This is a very powerful and hard sentence that is being meted out to a fallen angel.

[LiteKeeper]

INTREP - and the "facts" story changes once again.