This pointy-nosed shrew, a new fossil find from China, may be the earliest grandmother of all placental mammals, scientists report in a new study. Or perhaps she is the oldest great-aunt. Either way, it's another big find this week in paleontology.
The new shrew, Juramia sinensis, is the earliest known example of a placental mammal, which (unlike egg-laying monotremes and pouch-carrying marsupials) gives live birth. All placental mammals — from you to dolphins to bats — diverged from an animal like this one. Its discovery pushes back the marsupial-placental mammal evolutionary divergence by about 35 million years, to 160 million years ago, according to researchers in China and the U.S. This corresponds with DNA research that predicted an earlier divergence than the oldest previously known sample, Eomaia, which was 125 million years old.
The new fossil serves as "a corroboration of the newest fossil record with the molecular clock of evolution," according to the researchers, led by Zhe-Xi Luo of the Carnegie Museum of Natural History in Pittsburgh.
The shrew lived alongside the Jurassic-era dinosaurs, likely living in fern forests and feeding on insects. It was unearthed in a fossil field in China's Liaoning Province, where paleontologists found most of its skeleton, all of its teeth, part of its skull and, as Scientific American points out, even some hairs.
Understanding the evolution of placental mammals, also called eutherians, is key to understanding general mammalian evolution, the researchers said.
Luo and colleagues from the Chinese Academy of Geological Sciences and Beijing Museum of Natural History embarked on a detailed study of the shrew's teeth, which they say represent an ancestral version of modern mammal molar arrangement. Some characteristics of its arms and wrists also represent early eutherian characteristics, the researchers report. Its hands were able to grip objects, which suggests the mammals climbed trees. This ability may have helped the animals exploit new territory, further driving their evolution as distinct from monotremes and marsupials.
The naming of the shrew reflects its importance to mammalian heritage, the researchers explain: Jura means Jurassic; maia means mother, in reference to the placenta; sinensis means "of China." The name means "Jurassic mother from China."
The shrew is described in this week's issue of the journal Nature.
i don't really know what to think these days!!!
I find it sad that the only indication that evolution is merely theoretical and has never been proven is the the use of the word "hints" in the title.
evolution is not merely theroretical, the fact that organisms change over time is a well documented fact, the only theoretical part of evolution is what causes this to occur, natural selection is the scientific theory that explains how this occurrs, it is so obvious that organisms change over time considering the world of the dinasours is long gone, replaced by a entirely different ecosystem (which has occurred more than once and will again), referring to evolution as a theory should stop, this only confuses laymen that think a theory is the same as a hypothesis; theory, as used in science, is something that has so much evidence supporting it that it is believed that it will not be disproven, an example would be the theory of gravity
Drchuck1, natural selection is when an animal is better suited to success than others, so the others die out and the animal survives. This does not even help evolution. First, all documented cases of natural selection do not show any evolution at all. To prove evolution, you need macroevolution, the changing of species, not microevolution, the changing of superficial attributes. In every documented case of natural selection, there has simply been a change in color or behavior. The species involved did not evolve. This is the same as humans changing skin color or eye color, and does not prove evolution in any way shape or form.
mjmlacrosse...read a science book, they all say you are wrong
I'm a Christian and this bashing of the theory of evolution is disturbing to me. Folks, science and religion need not be in conflict. I decided long ago that God is more an engineer than a magician. (I'm not a Bible scholar, but I believe the only "science" in the Bible is in Genesis. After that, it seems to me that God's more interested in telling us how to live a happy and fulfilling life and how get along with each other than how old the universe is. My opinion, of course.)
P.S. - if you want to tear down a theory, pick on quantum physics. Seems like there's a lot of hocus-pocus going on there (particles blinking into existence from nothing and quickly annihilating each other; 4 dimensions? No, wait, 6, uh, no, 9. Maybe 10; depends.). I think you could propose Divine Intervention at the sub-atomic level and have a good chance of making it stick.
Can you not disprove the information I just told you to support the theory you believe?
Not sure if your comment was directed at me or not. If you are looking for a debate, I'm not interested. Feel free to continue to believe as you do. However, if you have some solid scientific references you can provide that detail the differences between natural selection and evolution, and how you can have one without the other, I'll be happy to skim them.
Evolution is a hoax. Just like the famous Lucy was proven to be a fake and a hoax, the THEORY of evolution will be proven to be total BS. Nothing has ever been observed, evolving…and it never will.
The dinos died because of climate change..and guess what, there were no SUV’s back then…even if there was, they were foot powered..LOL.
Big difference between natural selection and evolution.
Lucy wasn't a fake. Consult the Wikipedia article: http://en.wikipedia.org/wiki/Lucy_%28Australopithecus%29
And, before you say that Wikipedia articles can be faked, I suggest you read through the 26 citations at the bottom of the article.
Also @Aldrons Last Hope: I have a sneaking suspicion that you are Trolling me. But just in case ... bacteria and viruses have been observed evolving. There are other examples of higher animals adjusting to environmental pressures as well. Popsci has posted a number of them. Perhaps you skipped them.
@mjmlacrosse - There is no dividing line between species other than the classification given by humans. To say evolution is invalid because we haven't witnessed things evolving "cross-species" is a ridiculous argument.
The only difference between macro-evolution and micro is time and scale. We KNOW micro-evolution happens, so it's easy to extrapolate over time that huge changes are inevitable.
If you are actually interested in learning you could look at this e-coli experiment that's been going on since 1988 (http://en.wikipedia.org/wiki/E._coli_long-term_evolution_experiment). They've witnessed the bacteria evolve some amazing abilities not seen by bacteria in the wild. One of the 12 cultures actually evolved the ability to use citrate as an energy source. This is amazing because the e-coli's lack of ability to use citrate is a defining characteristic of the species. So does this mean we've seen a species evolve from one species to another?
And that experiment is only 23 years old, imagine the changes if the experiment were to continue for 4 billions years.
"The only difference between macro-evolution and micro is time and scale. We KNOW micro-evolution happens, so it's easy to extrapolate over time that huge changes are inevitable."
This is a fallacy. In a river, the water flows downhill, except in an eddy behind a boulder, where it turns to flow uphill. Evolution demands that life is such a situation where the abundance of energy moving "downstream" (entropy) is sufficient to justify uphill movement (evolution).
Evolution demands that speciation through selection (the observable phenomenon) is consistant and life is regionallized enough to create the incredible diversity of life the planet has known.
The problem is twofold, however. One, the overall diversity of life is, and has been for some time, on a consistant decline. Thus, even if evolution was a past phenomenon, it seems unlikely to be a future one. If you can posit a discontinuation in the future, then you cannot hold to a continuation into the past. Saying that "human intervention" is an outlying event causing the discontinuation puts humanity out of the natural order - a supposition untenable to the evolutionist (if humans evoloved, we are natural, along with all of our actions).
The second problem is with science. Science demands evidence and experimentation. Replication is necessary for science. Evolution, indeed, any past phenomenon cannot be science - only specualtion. Even if you could take life from chemical to kangaroo in a controlled experiment, you will only prove that evolution COULD have been the way life came to be, you can never prove that is HOW it came to be.
Even that snotty little Brit Dawkins has conceeded that life on this planet could have been intentional, intellegent design from extraterrestrials who developed from evolution (or developed from others, who developed from other, etc back to an evolutionary beginning).
"Even that snotty little Brit Dawkins has conceeded that life on this planet could have been intentional, intellegent design from extraterrestrials who developed from evolution (or developed from others, who developed from other, etc back to an evolutionary beginning)."
I would LOVE to see the quote from that snotty little Brit where he contradicted everything he ever said before!
"Dawkins is an atheist and humanist, a Vice President of the British Humanist Association and supporter of the Brights movement. He is well known for his criticism of creationism and intelligent design. In his 1986 book The Blind Watchmaker, he argued against the watchmaker analogy, an argument for the existence of a supernatural creator based upon the complexity of living organisms. Instead, he described evolutionary processes as analogous to a blind watchmaker. He has since written several popular science books, and makes regular television and radio appearances, predominantly discussing these topics. In his 2006 book The God Delusion, Dawkins contends that a supernatural creator almost certainly does not exist and that religious faith is a delusion—a fixed false belief. As of January 2010 the English-language version has sold more than two million copies and had been translated into 31 languages, making it his most popular book to date."
I have a theory for you, people who deny evolution, have a need to believe a story that EVOLVED over thousands of years that tells the weak minded that they will live forever in heaven.
There are so many implicit proofs for evolution all around you but you are willing to overlook them because you are afraid of your own little universe ending the day that you die. Simple.
Posted by another snotty little english man.
@rettaH_daM, sorry, my comment was not directed at you. It was directed at drchuck1. Mjolnir, please tell us some of your "implicit proofs" of evolution. @rettaH_daM, please link us to the articles you are referencing.
One giant thing that disproves evolution is the various examples proving that the earth is not 5 billion years old. First, the declining rotation of the earth. Lord Kelvin first noticed this, and realized that if the earth was actually billions of years old, the centrifugal force in earlier times must have been so great, life would not have survived on earth. Second, as the sun is giving us energy, it loses it, shrinkigng at a rate of five feet per hour, meaning that in prehistoric times, the sun would have been larger than the earth's orbit! Third, the earth's magnetic field is decaying quickly. There may not even be a magnetic filed in as little as a thousand years.
mjmlacrosse: Since you provided no references, I have, as well as the refutations for every point you raised.
Lots more young earth arguments at that site as well. But of course if you cite them, you won't omit the refutations, now will you?
"Facts do not cease to exist because they are ignored." Aldous Huxley
@Blodo, okay, but lets see you try to refute some of the main arguments of evolutionists. First, how did the first cells form? Are we to suppose that all of the neccasary systems for life, such as DNA, the reproductive system, RNA, and the parts of a cell, such as the cell membrane and the mitochondria, simply appeared? The chances against that are infinitely small. And what about the mutations, which are actually deformations of the genetic code and do not provide more desirable traits?
Also, what about the evolution of the eye, which evolutionists attempt to explain by saying it must have evolved from a light sensitive patch onthe skin. How did the extremely complex chemical reactions in the eye evolve? Mutations?
@mjmlacrosse...since your original comment was directed at me i guess i need to repeat myself,i will be a little more blunt since your reading comprehension seems a bit low, i am not here to prove you or anyone else correct, read a science book and i am sure you will discover all the researchers in the fields you bring up disagree with you, period, no if ands or buts, your thinnly disguised attempt to discuss religion as science is laughable at best, sorry, but you really should have listened to your science teachers
You see, the thing about conspriacy theorists such as our friend from california, is that they have a fixed idea i.e. god created everything in 7 days just like that book says, and just like the preacher told me. And then they hear about implicit proofs of evolution that are all around them, like THE FOSSIL RECORD. You can literally see thousands of different species CHANGE over thousands of generations. And then they see TV shows with smart people talking about all the 'book learning' they have done and the experiments that they have done that prove things, and they say RUBBISH! How can this be. It is far too unlikely that things can just evolve, and OH YES it doesnt fit the story of a book that has been made up by and adjusted by hundreds of people over 2 thousand years to meet the needs of their specific agendas. Such as the demonisation of Mary.
If these people READ something instead of just spouting what they hear from other nay sayers they may understand. Scientists will often refute the work of the predessors, e.g. http://jhered.oxfordjournals.org/content/96/3/171.full (try reading this).
The point is that the understanding of scientists is changing (some might say even EVOLVING), but the nay sayers point of view is always the same.
Try reading a book and having an open mind. Who knows, if there is a god, he may have started all this of with the big bang, and evolution is HIS plan.
I personally wont be waiting to sit on a cloud and play a harp when my lights go out.
It is so easy to sit hear, and look around us with billions of years of evolution having occured and say 'WOW, how did all this happen? It is all so complex! MUST be the work of god'. Our understanding of this has been developed by hundreds of people and guess what, HUMANS ARE STILL EVOLVING, and there is genetic PROOF of this. See http://www.bbc.co.uk/sn/prehistoric_life/human/human_evolution/
Oh, and on a final note, fossils dont just contain the remains of dinosaurs!!!!!!!
READ A BOOK!
i couldn't of said it better
Can you give me one example of an animal evolving, an example that has multiple verifications in the fossil record, and has not already been disproved? And I noticed neither of you tried to refute my recent argument.
there is simply no hope for you. Have a nice life
@rettaH_Dam, lucy has been proven to be nothing more than an ape.
There is no missing link, evolution is a complete myth invented by satanists.
see comment below that was below the article that you quote.It says it all, open your mind.
As a student of anthropology, I can guarantee you that this article is fraught with blatant errors and circular reasoning. As a Catholic, I have to ask why people find it so comforting to pretend that we spontaneously appeared on this planet. We are a part of the earth, not above it. Hiding from that truth is all this article accomplishes. The creationist myth gives us an excuse to leave our responsibilities to the earth as a species, in blind search of the infathomable concepts of grace and divinity. Creationists abandon their humility when they claim that we are separate from nature. Separation implies that we are above nature. When we forget our place on earth, we are sacrificing the abundant truths of nature for a constructed, prepackaged, manufactured set of ideals and mores (religion). Learn to accept the fact that we are a part of it. Find God for yourself, don’t blindly follow your institutions. And the fact that the vast majority of these responses are made by kids in grade school is terrifying. You have to understand that these arguments are based on man’s interpretation of God’s will, not on God’s will itself. We cannot understand God. The church uses the concept of God to repress change, as it has throughout history. This article is clear evidence—they have fed you factual errors and unfounded logic to make you resist change. Get out there and learn, go outside of your pre-constructed boundaries, and discover your individual beauty as a part of the natural world, and you will find spirituality.