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An artist depicts "Jurassic mother", the earliest known ancestor of man, merrily scampering through trees in the hunt for juicy bugs.  (Source: Mark A. Klinger / Carnegie Museum of Natural History)

The discover was made in China's northern Liaoning province, which borders North Korea.  (Source: Wikimedia Commons)

The skeleton was painstakingly reconstructed to reveal its secrets.  (Source: Nature/Beijing Museum of Natural History)

The fossil was dated to 160.7 million years old +/- 0.4 million years, making it the oldest known placental mammal. The fossil was dated by measuring radioactive argon in surrounding sanidine deposits.  (Source: Geowiki)
The 160-million year old mammal marked the split between placental mammals and marsupials

"You and me baby ain't nothing but mammals..." - Bloodhound Gang

Scientists may have just found mankind's oldest relative -- the "Jurassic mother from China", Juramaia sinensis.  The fascinating beast fills in crucial missing details in the fossil record of history's evolutionary tree.

I. A Tiny Rat, A Giant Discovery

The skeleton of the rat-like creature was discovered in Liaoning Province, a northern province of China that borders North Korea.  The skeleton was then analyzed by Zhe-Xi Luo, a Carnegie Museum of Natural History paleontologist; Chong-Xi Yuan and Qing-Jin Meng, Chinese Academy of Geological Sciences researchers; and Qiang Ji, a paleontologist at the Beijing Museum of Natural History.

The fossil including impressions of soft residual tissues like hair, an incomplete skull, and a partial skeleton.  The skeleton contained the forepaw bones (the "hand" bones in a mammal paw) and the skull contained a full set of teeth -- both valuable in identifying the creature's identity.

Examining those bones allowed the researchers to identify the mammal as a eutherian, a group of extinct mammals.  Furthermore, they establish that the creature was a placental-eutherian.

Placental-eutherians are distinguished for having a placenta when pregnant -- similar to man and most other modern mammals.  The placenta is a special organ in the uterine wall that handles resource exchange with the developing fetus.  Marsupials ("metatherians") -- such as kangaroos and opossums -- do not have a placenta when pregnant.

II. Discovery Resolves Evolutionary Discrepancy

The discovery solves a puzzling mystery.  Advanced modern genetic analysis had indicated that the placental-eutherian clade had diverged from marsupial-eutherians approximately 160.7 million years ago.  But until now the oldest placental-eutherian was the "dawn mother" Eomaia -- a 125 million year old rat found in China.  Now the genetic evidence and fossil record are in agreement.

The fossil was dated using the 
40Ar/39Ar method on sanidines -- high temperature feldspars -- in the local sediment.  That dating method was accurate to place the age to within a +/- 400,000-year range.

Man's ancestor was more fur than fight, though.  It weighed around one pound soaking wet and its specially adapted paws allowed it to scurry around in tree avoiding the numerous dinosaur predators that stalked the ground.  Its sharp teeth indicate that it feasted primarily on a diet of bugs.

Professor Luo comments
, "The divergence of eutherian mammals from marsupials eventually led to placental birth and reproduction that are so crucial for the evolutionary success of placentals. But it is their early adaptation to exploit niches on the tree that paved their way toward this success."

In an interview
 with MSNBC, he adds, "I imagine this animal to be a shrew-sized insectivorous mammal that hunted insects and was capable of being active in the trees."

The work is published [abstract] in one of science's top peer-review research journals, Nature.

III. Work is Lauded as Groundbreaking Discovery

Often critical studies such as this one draw a great deal of debate and criticism as not all experts are convinced. In this case, however, the community of paleontology experts seems virtually unanimous in their praise of the work, which they say is a vital leap for the field.

States Gregory Wilson, an assistant professor in the University of Washington
’s Department of Biology, "This new specimen is a real jewel among the spectacular treasure chest of the Chinese fossil record," Wilson said. "The exquisitely preserved anatomical details leave little doubt that we're looking at the earliest eutherian yet known not quite a placental yet but on the line to placentals."

"This significantly pulls several major branches of the mammalian phylogenetic tree even farther back into the Age of Dinosaurs, providing better understanding of the context of mammalian evolution. This work will grip the attention of paleontologists, molecular systematists, and anyone interested in their ancient forebears."

The brave little rat would thrive and flourish in the Chinese woodland eventually giving way to
newer eutherians like Eomaia.  After the mass extinction of the dinosaurs -- which occurred about 95 million years after the Jurassic mother rat -- they would descend from the trees, conquering the empty domain that dinosaurs left behind.  Over the next 65 million years a host of new mammal species evolved including -- eventually -- mankind.



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False echo
By navair2 on 8/28/2011 12:30:58 AM , Rating: 1
Sooo...Scientists are at it yet AGAIN, trying with ultimate failure to prove the THEORY of evolution by the fossil record...a record CREATED in the deluge of Noah's flood.

Yes, a flood that occurred some 4,500 or so years ago. BTW, a perfect environment for CREATING fossils, which scientists admit a cataclysmic event such as the Flood would have had to occur for fossils to be formed...

Said "scientists" are also unable to come up with ANYTHING linking man to apes since Piltdown, Peking man and a few others have been reliably discredited as having been builtup from the fossil remains of ANIMALS.

Nice try, but still ultimately a RAT.




RE: False echo
By PReiger99 on 8/28/2011 8:08:28 AM , Rating: 2
http://troll.me/images/futurama-fry/not-sure-if-tr...

If you believe that a magical world wide flood (water coming out of nowhere) created a large quantity of layers in the ground then you suffer from an hopeless case of scientific illiteracy. Such imaginary flood would only create a single thick layer (geology 101), not only that but more simple and less complex organisms wouldn't be at the bottom while more evolved on the top (evolutionary order). But I guess you also believe that an old bearded man just build a oil tanker-sized ship... out of wood (who knew that ship building was so well understood back then considering that the Santa Maria was "just" 75 feet long and was build about 4000 years later by a society much more technologically advanced).


RE: False echo
By KnowledgeInternet on 8/29/2011 3:50:10 PM , Rating: 2
Also, archaeological evidence shows undisputed evidence of uninterrupted human societies on all continents continuously thoughout the past 10,000 years - evidence that the World (Earth) did not flood. Asia, Africa, Europe, SouthEast Asia (The Middle East) and The Americas have evidence of human settlement, uninterrupted, THROUGH the time period of this alleged "global flood." Did a downpour of rain from the mountains north of Mesopotamia/Sumer result in a massive flood causing the Euphrates and other rivers in the flat region of Mesopotamia to overflow their banks and "flood" civilization (Think of modern river floods - the land LOOKS like a global flood) ? Yes, archaeological evidence REVEALS that.


RE: False echo
By lagomorpha on 8/28/2011 4:14:09 PM , Rating: 2
Please be a troll.

http://www.fromoldbooks.org/Stone-AmericanAnimals/...

That is an example of a rodent skull. Notice the large incisors. The picture from this article is a species that no longer exists on earth, it has either died out with no progeny or its descendants evolved into other things.


RE: False echo
By CharonPDX on 8/29/2011 2:56:46 PM , Rating: 2
YAY TROLL!

Not a very good troll, either. Too obvious.

Thanks for playing, please try again.


RE: False echo
By navair2 on 8/29/2011 8:52:34 PM , Rating: 2
I'm not playing. I'll continue to believe God's Word over "scientists" who just can't seem to get "it" right. Mankind is so determined to PROVE God wrong they'll believe anything.

As for Noah's flood, if Turkey would let anyone get up to Mt. Ararat, you might see footage of the real vessel. But as long as their government forbids archeological expeditions from going, we won't know, will we?

Now...perhaps someone forgot to tell the truth about some things in recent "digs", such as dinosaur footprints side-by-side with a man's prints in FOSSILIZED ROCK discovered in Texas some years back...or the Plesiosaur carcass dragged up by a Japanese fishing trawler in 1977...or the Coelacanth found alive in 1938, when it was SUPPOSED to be extinct?

This article is nothing more than sorry "research" done by people who don't really KNOW and will continue speculating. I'll trust the Lord, He makes much more sense....;)


RE: False echo
By Skywalker123 on 8/29/2011 11:43:05 PM , Rating: 2
I don't think he's a troll, he's really that stupid


RE: False echo
By lagomorpha on 9/1/2011 2:59:54 PM , Rating: 2
I don't think he can possibly be that stupid, the last post gives it away. Not to mention the idea that some old guy built a boat large enough to house enough animals to repopulate the earth.

"if Turkey would let anyone get up to Mt. Ararat, you might see footage of the real vessel. But as long as their government forbids archeological expeditions from going, we won't know, will we?"

Many towns in Turkey actually make a considerable amount of money from Christians going there on pilgrimage in an attempt to locate Noah's Ark. They generally wander around the mountains for a few weeks digging around and spending money until they give up. Every other year someone even claims to have found a piece of the Ark which always turns out to be a board from some several hundred year old building.


RE: False echo
By mritter1981 on 9/1/2011 6:09:24 PM , Rating: 2
However it should also be noted, that there is no emperical evidence of "God", or intelligent design either. Honestly I'll take the word of a scientist, which the catholic religion once touted as wizards, and subsequently killed. Over the supposed words of a magic man in the sky. Science also shows no racism. Religion does. How many wars were fought over different scientific theories? How many over differences of religion?


"A politician stumbles over himself... Then they pick it out. They edit it. He runs the clip, and then he makes a funny face, and the whole audience has a Pavlovian response." -- Joe Scarborough on John Stewart over Jim Cramer

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