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An artist's rendition of Haplocheirus sollers  (Source: Portia Sloan)

The skull of the beast shows similarities to its cousins, the ancestors of modern birds. However, the creature's lacks some of the bird-like features of later members of the family, showing that the features likely evolved in parallel in both birds and the related dinosaur group.  (Source: NSF.gov)
Newly discovered dinosaur shows that in evolution lightning can and does strike twice

A newly discovered dinosaur in the Alvarezsauridae group has revealed that bird-like features likely evolved twice, both in dinosaurs and in the ancestors to modern birds.  Previously, the group was thought to be ancestors of modern birds, rather than evolutionary cousins. 

Describes Jonah Choiniere from George Washington University in an interview with BBC News,  "Haplocheirus is a transitional fossil.  Previously we thought the Alvarezsauridae were primitive, flightless birds. This discovery shows they're not and that the similarities between them evolved in parallel."

Like birds, the group of dinosaurs has fused wrists and loosely assembled skull bones, leading many paleontologists to believe that they might be the ancestors of birds.  The beasts may also have had feathers, according to analysis in the late 90s and onward.

However, anatomical analysis of a 3-meter long nearly complete skeleton of a new species in the group indicates that the group likely diverged from the line of dinosaurs that evolved into birds, and that the bird-like features emerged in parallel, not in series.  The new skeleton was dubbed Haplocheirus sollers and was found in the China's Gobi desert.  The skeleton was noticed by a member of a team excavating in the orange mudstone beds in the Junggar Basin of the Xinjiang province.  The member saw the pelvis of the dinosaur sticking out of the ground -- and the rest of the skeleton was found soon after.

Professor Choiniere describes, the results of the subsequent analysis, stating, "The rest of the members of this group have really short forelimbs with huge muscle attachments, like body-builder arms. The fossil shows the first step in the evolution of this weird arm and claw."

The new dinosaur is thought to have lived 160 million years ago, making it the oldest member of the family found to date.  Birds and Alvarezsauridae likely split not long before the evolution of the new find, say researchers.  Both group s likely are descended from the bird-footed dinosaurs of the early Jurassic, which include such famous members as the T. Rex and Velociraptor.

The new find likely was primarily an insectivore (as evidenced by its small teeth).  Its small claws were quite agile and would have been ideal for digging, leading researchers to speculate it likely ate termites, which were plentiful in its era and locale.  However, that likely didn't stop the versatile reptile from trying different cuisine. Describes Professor Choiniere, "It may have had a very general diet, tackling smaller animals like lizards, very small mammals and very small crocodile relatives.  It was a lightly built animal and could run very quickly."

The new work was reported in the journal Science.

The truly fascinating thing about this find is that it fuels the theory that in evolution lightning can, and likely will strike twice -- similar designs can evolve in parallel out of a common need.  Thus much of the anatomy in science fiction -- such as teeth on the titular Alien or giant wings and feathers of the flying monsters of Avatar -- may be realistic.  If life is found on other planets similar to Earth, it may show striking similarities as our own planet's fossil record indicates.



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By Mitch101 on 2/1/2010 4:39:14 PM , Rating: 1
http://www.gotquestions.org/human-chimp-DNA.html

Question: "Is the similarity in human/chimp DNA evidence for evolution?"

Answer: In recent years, genome mapping has enabled detailed comparisons between the DNA of humans and that of chimpanzees. Many have claimed that humans and chimpanzees share over 98% of their DNA. This is often taken as decisive evidence of the common ancestry of apes and humans. But is this argument tenable? Is this really a fact which definitively proves a human-chimp common ancestry? It is our contention that the percentage is misleading. In fact, when the data is examined more closely, the human-chimp genome comparisons turn out to contradict what would be predicted by evolution.

In reality, the genetic differences between humans and chimpanzees are probably greater than 2%. More recent studies have shown that the true genetic divergence between humans and apes is probably closer to 5%. Thus, the “over 98% similarity” argument is probably an overstatement.

The differences between the DNA sequence of the human and the chimp are not distributed randomly throughout the genome. Rather, the differences are found in clusters. Actually, at those specific locations, the chimp’s genome is similar to that of other primates. It is the human that stands out from the rest. Scientists often refer to these ‘clusters’ as human accelerated regions (HAR’s) because the human genome supposedly shared a common ancestor with chimps. These HAR’s are located in DNA segments that do not code for genes. But this requires us to believe that evolution just so happened to cause such rapid change to occur in sites where those changes make an important difference in an organism’s functioning necessary to ultimately create a human.

Such would be a whopper of a just-so story. But it gets better. Some HAR’s are found in DNA segments that do code for genes, and herein lies another multitude of difficulties. Evolution would predict that humans evolved from the chimp-human ancestor via natural selection acting on chance variations induced by mutations. However, recent research reveals just the opposite. The HAR’s that were found in protein coding genes showed evidence not of mutations that had been selected in view of their advantageous phenotype, but rather the exact opposite. The genetic changes showed evidence that they were, in point of fact, deleterious. They had become established in the population not because they provided some physiological advantage, but in spite of being deleterious. Such results make little sense within an evolutionary framework.

Clearly the HAR’s show a trend in which the differences observed in the human DNA (as compared to similar species) typically increase the G-C content of that particular region of the DNA strand. Evolution would predict that the G-C content of the underlying gene should remain relatively constant, as natural selection picks out the DNA mutations that improve the protein. If evolution is true, therefore, we should not expect a consistent trend toward an increasing G-C content.

These HAR’s are not always limited simply to the protein coding part of the gene, but often extend beyond the border into the flanking sequences. This further suggests that these differences which are observed in the human DNA are not in fact consequences of natural selection enhancing the protein that the gene encodes. The HAR’s often tend to cluster in a single part of a gene, in and around a single exon (as opposed to across the entire gene), and they tend to correlate with male (but not female) recombination. Such observations make little sense in light of evolution.

In conclusion, as interesting as genetic similarities between chimpanzees and humans are, they are not evidence for Darwinism. Design is also able to explain them. Designers often make different products by utilization of similar parts, materials and arrangements. The common percentage pertains to the regions of our DNA that result in proteins. It makes more sense of the data for the Designer of nature to have used the same proteins to perform the same function in a variety of organisms.


By Keeir on 2/1/2010 7:04:39 PM , Rating: 3
The significant problem with Intelligent Design, Mitch

It all comes down to Faith.

The function of evolution does not require there to be Designer, nor does the function of evolution preclude the possibility of a designer.

Intelligent Design requires you to take it on faith that a Designer made the changes. There can never be proof of this occuring (unless he happened to write a very specific tag line or some such. Maybe in the future we will indeed find a series a genes that serve no other function besides as a signature).

Your examples in the above post may seem great to you, but they in reality say nothing.

Its pretty funny that its suggeted that simply sharing somehwere between 95-98% rather than 98% of the same genes should be considered an arguement against Darwinism.

The existence of genes that currently provide no benifit, or even negative, does not contradict evolution Theory at all, it simply shows that evolution is continuing or the gene itself is not properly understood.

A good example of improper understanding is the common Bee type insect. Vast number of worker bees apparently support a single reproducing queen and a small number of reproducing males. Why would evolution cause such a difference? Surely this is a mistake!?! I mean, a single reproducing female has apparently forced dozens of non-reproducing workers to feed it and take care of it... for no direct gain. Yet it turns out that due to the genetic composition of bee type insects, its in the worker bee's genes' best interest to create -more- worker bees. This is the closest match in terms of genetics to the current worker bee. When colonys of Bee type inspects are tested, the most populous type of bee is almost always the female worker bee. Even when the situation exists that larger numbers of reproductive queens/males could be supported, the tendency of the bee type insect is to maximize the worker population... sense it made. No Faith is needed that for some reason a Design (or Wizard) decide to "Do it that Way".


By Gzus666 on 2/1/2010 8:03:36 PM , Rating: 1
quote:
http://www.gotquestions.org/human-chimp-DNA.html Question: "Is the similarity in human/chimp DNA evidence for evolution?"


http://www.talkorigins.org/faqs/comdesc/section4.h...

Looks like scientists took the liberty of answering your copy and paste job that you apparently have no understanding of, but since it is written by morons who think the bible has answers, you take it as gospel (ironic, I know).

If you care to see someone else discount it...

http://forum.richarddawkins.net/viewtopic.php?f=46...

Basically, you are a puppet. You have no understanding of what you are talking about, so you copy and paste garbage you found on a creationist BS website. If you have evidence evolution doesn't work, present it. Otherwise, you have no argument. Every silly joke of a post on that website has responses from legitimate science studies to show they are false. That is the same website that has the balls to say that the second law of thermodynamics disproves evolution. Of course they don't read the whole law or cherry pick so they can cater to idiots who follow their religion (most likely the latter, since the leaders of such cults tend to be sociopaths) and forget to notice the part about a closed system. Even scarier would be if they didn't know the Earth wasn't a closed system...

Hopefully you can see why I can't take your "evidence" seriously. When you disprove the mechanism of evolution, let me know.


By porkpie on 2/1/2010 11:19:26 PM , Rating: 2
quote:
"The genetic changes showed evidence that they were, in point of fact, deleterious. They had become established in the population not because they provided some physiological advantage, but in spite of being deleterious. Such results make little sense within an evolutionary framework."


S****! not this nonsense again. Do you honestly not realize that a particular mutation may be advantageous in one setting, but deleterious in another? A classic example is sickle-cell anemia. In malaria-prone climates, having a single copy of this "defect" provides resistance to malaria. Elsewhere, its just a problem.

Much of our genotype is excess baggage, carried over from millions of years ago. It made sense at the time and place, biologically speaking, but does not today. Trying to use this as 'proof' that some god or gods made is childishly naive.



"Young lady, in this house we obey the laws of thermodynamics!" -- Homer Simpson














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