Posted on 05/07/2008 10:44:35 AM PDT by blam
Platypus genome is as weird as its looks
18:00 07 May 2008
NewScientist.com news service
Emma Young
It's part-reptile, part-mammal, part-bird and totally unique. Two centuries after European scientists deemed a dead specimen so outlandish it had to be a fake, the bizarre genetic secrets of Australia's platypus has been laid bare.
Platypuses lay eggs and produce venom like some reptiles, but they sport furry coats and feed their young with milk like mammals. The odd creatures are classed as monotremes, with only one close relative the echidna.
But as primitive mammals that share the same ancestor as humans, a study of the animal's genome can improve biologists' understanding of how mammals evolved, while illuminating the platypus's strange physiology.
Wesley Warren at Washington University in St Louis, Missouri, led the international team that sequenced the platypus genome. As expected, they found an amalgam of some ancestral reptile and some newer mammalian features. But there were also surprises.
Ancient milk
And while the gene that the human sex-determining gene evolved from is present in the platypus genome, it seems to have nothing to do with sex determination. So, that function must have evolved after the platypus split from our common ancestor, about 166 million years ago.
However, by that time, milk production was well-evolved. The platypus has the same repertoire of milk protein genes as a cow or a human. Clearly, milk evolved long before we evolved to give birth to live offspring, says team member Jenny Graves at the Australian National University in Canberra.
The team also investigated the genes for the platypus toxin, which males deliver via a barbed spur on their heel. While the toxin is similar to a snake's adapted from natural neurotransmitters and other proteins
(Excerpt) Read more at newscientist.com ...
Ehh wot? Platypus milk is perfectly serviceable in feeding baby . . . platypi? platypuses?
And
In their universe, that original statement makes no sense; that a biological feature will evolve, to satisfy a need thousands, perhaps millions of years later.
im not angry....i just like to emphasize.
there are no transistional fossils, there is no definition to give, except in the minds of evolutionisms adherents, and that is mainly because the theory desparately requires it.
Your framing of that sentence gives us a hint that you have a better explanation.
Go on, put your money where your mouth is. Provide us an alternative explanation, substantiated by physical and factual evidence.
http://news.bbc.co.uk/2/hi/science/nature/680116.stm
Friday, 17 March, 2000, 12:43 GMT Discovery challenges snake origins By BBC News Online science editor Dr David Whitehouse The view that snakes originally evolved from sea-living lizards may have to be rethought, say scientists who have analysed a fossil serpent with legs. The creature was found in 95-million-year-old sedimentary rock near Jerusalem. The well-preserved specimen, called Haasiophis terrasanctus, is the second, legged snake species to come from this particular site at Ein Yabrud.
It was from studies of the first species, called Pachyrhachis problematicus, that researchers got the idea that modern snakes might have descended from giant swimming lizards from the Cretaceous period (144-65 million years ago) called mosasaurs. Pachyrhachis was viewed as an intermediate step, displaying features that lay somewhere in between those of the marine creatures and today's snakes. But the better detail in the new fossil challenges this theory, claim Dr Olivier Rieppel, of the Field Museum in Chicago, and Professor Eitan Tchernov, of the Hebrew University of Jerusalem. Their research not only suggests that Haasiophis and Pachyrhachis were closely related, but that the two creatures were actually quite advanced. They do not easily fit into our existing theories on the origins of snakes. Massive gape The scientists looked closely at skull features, which are remarkably similar to boas and pythons. These modern snakes have a distinctively mobile skull structure that allows them to nearly unhinge their jaw in a formidable gape. This allows them to eat very large prey. The two fossil snakes look as though they had a similar ability. "We went back and looked very carefully at the skulls of Pachyrhachis, Haasiophis, and lizards like mosasaurs, looking at features like the braincase, the dentition, and the joint in the middle of the lower jaw," says Dr Rieppel. "The better preservation of Haasiophis allowed us to use its anatomy as a guide, and gave us the background to see just how much these fossils looked like advanced snakes." And both snakes appear to have unsnake-like hind limbs which researchers speculate have evolved more than once during the snake's evolution. Scientists suggest that the snakes with advanced skull design regained hindlimbs that were lost by evolution. Use of claw "We know of at least 62 lizard and snake lineages that have undergone some degree of limb reduction," Dr Rieppel says. "Since our fossil record of snakes is very poor, we can't exclude the possibility that limbs in snakes were lost not just once in the beginning, but several times throughout their history." Dr Rieppel says that after studying the new fossils it is difficult to tell how the legs themselves might have been used, since they are too small in relation to the animal's whole body to have been of any use for movement. Modern pythons have a rudimentary hindlimb, usually little more than a "claw" of cartilage tipped with bone that they use during mating and occasional fighting, and it is possible that the Haasiophis leg served a similar purpose. The researchers conclude that Haasiophis and Pachyrhachis are not related to primitive mosasaurs. Dr Rieppel says he believes the ancestors of modern snakes were burrowing lizards that lived on land. However, he acknowledges that the West Bank fossils do not provide clear answers to the question. Professor Tchernov told the BBC that a new project would start shortly to uncover as much material as possible from the rich and well preserved Ein Yabrud site. "We hope we will come out with other sensational finds," he said. "Because this is very close to Jerusalem, we have this kind of Holy Spirit around this geological section which somehow is associated with the history of snakes." The research is reported in the journal Science.
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So, you will accept no scientific evidence for evolution?
tastes like chicken
You are correct. And mammals aren't the only class of animals in which parents internally generate nourishment for their offspring. Some birds, such as pigeons, slough their esophageal cells to produce a nourishing liquid that they can regurgitate and feed to their young.
See post #59.
The origin of Cloverfield?
These “Evolution/creationnism” threads never cease to amaze me.
I personally favour the evolution theory, mostly because it is backed by facts I can grasp - fossils, genetic similarities, species that clearly are evolutions from earlier life forms.
I do not think that these facts can be wished away by chanting “I can’t hear you LA LA LA LA”, or because the Bible doesn’t explicitly say “and the Lord said ‘grow, multiply AND evolve’ “
So, yes, I personally favour evolution. But WHAT is making specied evolve ? WHERE does that ability to adapt and evolve come from ? And WHY do species (and flora/fauna as a whole) evolve ? Darwin’s theory, in my opinion, explains what happens, not why it happens, just as astrophysics explain the rules governing the universe as we know them, but not the finality of the universe, or why it was created, or what is the purpose of this set of physics rules.
I remember watching interviews by astrophysicians who, despite having proof that the universe hadn’t been created as told by Genesis, were firm belivers in God. They thought God’s work was not so crude that is could be seen in astrophysical mechanics, and that as science allowed us to answer an increasing number of questions, the remaining questions only grew bigger.
Why couldn’t this be the same thing with the theory of evolution ? I can read my Bible and my science books any way I want, I don’t see why it couldn’t be that God Himself gave this impulsion to evolve.
If we are believers, then isn’t it vain to think we know for sure what God really had in His mind when He created the universe ? And if we are militant unbelievers who think science as we know it explains everything, we should remember that scientists have always been convinced their scientific explanations were built on rock-solid proof, only to be proven wrong time after time, by the likes of Galileo or Einstein.
Thank you.
Interesting posts.
You’re welcome!
"Tard" refers to the ping list members and not to the subject of the thread!
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BWAAAA!
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