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  (Source: Matt Groening/Fox)
Crucial gene controls higher brain growth

To the uninformed observer it may seem baffling how geneticists, biochemists, paleontologists, and other researchers can claim that two creatures that look as different as a man and a monkey could not only be "related" but have been produced by evolution over the last couple million years.

I. It's All in the Genes

But the key to understanding evolution is to understand genetics: our body is driven by protein enzymes, which catalyze critical processes inside the body.  Many proteins share common domains.  And the blueprints to all the proteins a creature makes are stored in a special highly-ordered storage construct called DNA.

While living organisms go to great lengths to preserve their genetic code without errors like swapped sections or deletions, occassionally during the process of making sperm and eggs such an error is made.  Most errors result in infertility or death of the offspring.  But occasionally just the right combination of protein domains has accidentally been clumped together, producing something that fundamentally transforms the organism.

Researchers have finally found a gene -- perhaps the gene -- which separates humans from the ancestors they share with apes.

Humans and apes, both members of the order Primates, share 96 percent of their genetic code.  Most of the remaining 4 percent is so-called "junk" DNA; stretches of mostly inactive code.

Rhesus macaque
Humans share 96 percent of their genetic code with primates, like this Rhesus macaque monkey.
[Image Source: Mark Snelson]

Of course, junk DNA is not useless geneticists and biochemists have recently discovered.  It has been shown to in many cases play a key role in regulation of other genes' expression and other "epigenetic" effects.

But researchers had yet to discover a truly active gene that humans have that apes lack -- until now.

II. miR-941 May Hold the Key to How Mankind is so Crafty

Researchers at the University of Edinburgh in Scotland have discovered a gene called miR-941, which is only found in humans and is absent in their primate relatives.

The gene was absent not only in the gorilla and chimpanzee genomes, but also in the genomes of other non-primates, such as mice and rats.  The gene, absent in all the other critters except for man, is mainly active in the brain; particularly in areas of the brain associated with so-called "higher brain" functions.  

The gene was actively being transcribed in the regions of the brain responsiible for language learning and decision making. Researchers hypothesize that it may play a key role in abilities that are largely unique to humans, such as formulating, understanding, and preserving multiple complex communications codes (languages) and developing advanced tools (weapons, machinery).

Human brain activity
The newly discovered human-unique gene is active in areas of the brain associated with higher thinking processes. [Image Source: Neuroimages Tumblr]

Some other creatures -- gorillas, parrots, dolphins, and whales -- show different levels of sign language or spoken/sung language skills.  And chimpanzees, octupi, and other creatures have been shown to use basic implements, like sticks, as tools.  However, only humans are known to manifest these helpful survival skills in more complex manners.

Now, modern genetics may have cracked a key mystery of human evolution and explained why.

The research was published in the prestigious peer-review journal Nature Communications.

Source: Nature Communications



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By Flunk on 11/23/2012 1:56:34 PM , Rating: 2
What's an "evolutionist", do you mean scientist? Most of what you've written here is nonsensical ramblings but I get the distinct feeling that you are under the misconception that evolution isn't the overwhelming scientific consensus here. At this point you would need an earth-shatteringly revolutionary discovery to disprove evolution at this point.


By ElConquistador on 11/23/2012 4:16:10 PM , Rating: 2
quote:
The theory of Evolution has never been upgraded to a Law because it has never met the requirements, nor will it ever meet the requirements

And could you please enlighten us as to which those requirements would be?
I'm sure many physicists would like to know, so they can finally promote that stubborn Relativity thingie from Theory to LAW


By LRonaldHubbs on 11/23/2012 9:11:12 PM , Rating: 2
quote:
I realise you don't think these have much to do with Relativity

WTF are you talking about? Both red shift (Doppler effect for light) and gravitational lensing are well-known phenomena described by Relativity. Why would anyone here not think that they have much to do with it?


By drycrust3 on 11/24/2012 12:40:28 AM , Rating: 2
quote:
... red shift (Doppler effect for light) and ... are well-known phenomena described by Relativity.

Is it? Thanks for the update, I was unaware that anyone else thought that pulsars were actually so distant galaxies that the light from them had red shifted to the point that the light had become microwaves, and that in the process the electromagnetic radiation fragmented into a series of pulses.


By drycrust3 on 12/4/2012 6:55:28 AM , Rating: 2
Just to let you know, if the cause of the red shift was gravitational red shifting, then I think that one can argue that c (as in the speed of light) isn't constant. It could be that what we see as star light has spent most of its time traveling through space as a radio wave, at much higher speeds than what we normally expect.


By drycrust3 on 11/25/2012 10:24:17 AM , Rating: 2
I did a search for images relating to gravitational lenses and found this website:
http://www.optcorp.com/edu/articleDetailEDU.aspx?a...
The interesting thing is all the images they show where light has bent due to the gravitational force of a mass are blue. I would have expected there to have been a range of colours, not just blue. This makes me think that there is something else happening here.


By drycrust3 on 12/4/2012 3:44:44 PM , Rating: 2
When I look at those Hubble pictures, it looks to me like gravitational lensing is quite common, and that the most popular colour is blue, and that multiple images of the same galaxy can occur.


By gladiatorua on 11/24/2012 3:39:22 AM , Rating: 3
Scientific theory can NOT be "upgraded" to a scientific law. RTFM(look up the descriptions)!
What you call a "theory" is actually a hypothesis. And with substantial proof it can become or be included into the theory. And hypothesis is not some shot in the dark. It has to have strong basis in reality and has to be disprovable.
SCIENTIFIC theories can not be upgraded or even proven. It's a body of work about phenomenon. It either works or it doesn't. Gravity, relativity, plate tectonics work. And evolution is a stronger theory than some of those.
quote:
In fact, we have people like Haeckel who fabricated evidence to try and prove the theory of Evolution was true.
Haeckel tried to prove his own hypothesis in the field of embryology, which is related to evolution but is not the same thing. Haeckel has nothing to do with credibility of the theory of Evolution.


By gladiatorua on 11/25/2012 9:22:29 PM , Rating: 2
His HYPOTHESIS - no.
He is usually mentioned.
If the book is any good he is either mentioned as a fraud or not mentioned at all.
And he published his drawings years after Darwin's work.
His REJECTED HYPOTHESIS was on embryology. His fraud was found out fast enough. Read the wiki.
As with most frauds the were somehow related to evolution, it's not the scientist that were fooled. Haeckel's book was aimed at general public. His "findings" spread like a wildfire and creationists got a powerful weapon and scientific community got the mess.


By xthetenth on 11/24/2012 3:31:01 PM , Rating: 2
quote:
The theory of Evolution has never been upgraded to a Law because it has never met the requirements, nor will it ever meet the requirements.


A law is a statement based on repeated observation that describes an aspect of the natural world. It has no predictive power.

A theory is a statement based on repeated observation that explains an aspect of the natural world. It makes predictions about the rest of the natural world outside the observed circumstances.

Those are the scientific definitions of a law and a theory. Kindly note that a theory is stronger than a law. In fact, if a theory is proven false in some circumstances it will be downgraded to a law for the circumstances in which it is proven false. For example, if a god shows up and starts changing animal's genomes, the Theory of Evolution would probably become the Law of Natural Evolution.

The reason for the stronger statements with predictive power being labelled theories is because science is obsessed with being correct, and no predictive statement is entirely verifiable. Laws are laws because they make no prediction and are therefore entirely verifiable.

quote:
It isn't even a very good theory, it is actually a very poor theory because one of the main traits of a good theory is being able to make predictions, and especially predict important discoveries, prior to proof of that discovery. Darwin didn't predict DNA, nor, as far as I know, did any of his disciples.


This is entirely backwards as well. It is a very good theory because what it predicts has been shown in every single fossil discovered and in the anatomy of every living being on the planet. The anatomy of every living animal shows the signs of common ancestry and the changes from that common ancestor being driven by a mechanism where if the marginal cost of any change to the animal is a net negative it is more likely to be passed on to its descendents and become more prevalent until it becomes the norm. It didn't predict a mechanism because it didn't need to. It's a prediction of a pattern of development followed by all of biology. The mechanism by which animals are changed is irrelevant to a prediction of the pattern those changes will follow. I could just as easily say the Theory of Relativity is a bad theory because it doesn't predict or explain Higgs Bosons. However, the predictions it makes are all verifiable, and it explains some important things, such as the perihelion shift of Mercury.

quote:
In fact, we have people like Haeckel who fabricated evidence to try and prove the theory of Evolution was true. In 1976 I went took my science book to the school library and compared Haeckel's drawings to the photographs in the Encyclopedia Britannica and the fabrication was plainly evident! If a theory is credible, then why do you need to fabricate evidence?


In the case of Haeckel you need to fabricate evidence because you aren't trying to prove the theory of Evolution in that case, you're trying to prove the Biogenetic Law (which has since been falsified and is discussed in depth here: http://9e.devbio.com/article.php?id=219 ). Basically he was trying to prove that the development of an individual organism passes through stages represented by adult representatives of its evolutionary ancestors. Among other things he predicted a linear phylogeny rather than a branching one in the way Evolution does, and that isn't borne out by the evidence. He did popularize Evolution but his later work was bad and just so happened to be on an incorrect hypothesis.


By JPForums on 11/29/2012 11:01:30 AM , Rating: 2
It seems some people around are confused about what Scientific Theory and Scientific Law are as well as the purpose of each. Wikipedia does well enough for a basic refresher.

Scientific Law
http://en.wikipedia.org/wiki/Scientific_law

Scientific Theory
http://en.wikipedia.org/wiki/Scientific_theory

Scientific Hypothesis
http://en.wikipedia.org/wiki/Hypothesis

quote:
A law is a statement based on repeated observation that describes an aspect of the natural world.
Yes.
quote:
It has no predictive power.
No. A law is demonstrable, always repeatable under the same conditions, and implies a cause effect relationship. Laws are constrained to the conditions under which they are observed. Laws applicability can be expanded when observed to be true under new conditions. If new data legitimately contradicts the law, it may be falsified. It has great predictive power in the sense that you can rely on the fact that if you affect the exact same conditions, the same result will occur. Otherwise the law would be falsified.

quote:
A theory is a statement based on repeated observation that explains an aspect of the natural world.
Yes.
quote:
It makes predictions about the rest of the natural world outside the observed circumstances.
No. Predictions are made based on the theory to test and verify the accuracy of the theory. Let me say that a different way. It has no predictive power. If you could affect the conditions of a theory and observe the result, thus demonstrating reliability, it wouldn't be a scientific theory. If observations are made that contradict the theory, it may be adapted to fit the new data or discarded for a theory that more closely fits the facts. Scientific theories are expected to change from their original conception.

Point of interest: Laws may be observed in the process of testing theories.

quote:
Kindly note that a theory is stronger than a law.
It's not. It is more comprehensive than Scientific Law, but it is also not both observable and repeatable; thus it is less reliable. It is therefore neither stronger nor weaker than Scientific Law. It simply serves a different purpose. Choose the tool appropriate to what you are trying achieve.
quote:
In fact, if a theory is proven false in some circumstances it will be downgraded to a law for the circumstances in which it is proven false.
No. No. No. If a scientific theory is contradicted, the theory is adapted to fit the new data or supplanted by a theory that more closely matches the currently available data. Scientific laws are observable and repeatable. Theories, whether true or false are not both observable and repeatable. They therefore cannot become a law unless for some reason they becomes so. Even then, it is more likely that a small portion of the scientific theory becomes a law or several laws as scientific theories are comprehensive, where scientific laws describe singular relationships. Furthermore, if anything is proven false, it fails the repeatable requirement. So a "false" scientific theory will never be "downgraded to law".

quote:
The reason for the stronger statements with predictive power being labelled theories is because science is obsessed with being correct.
Scientist have an obsession with explaining the world around them. I've seen far more excitement over contradictory observations from scientists than another run of supporting observations as it generally means they've found something new. As a side note, a real scientist will adapt theories to support facts rather than adapt facts to support theories.
quote:
Laws are laws because they make no prediction and are therefore entirely verifiable.
Scientific law starts out as a scientific hypothesis or in other words a testable explanation for a phenomenon. To be testable, you have to be able to define what results would prove or disprove the explanation. You are, therefore, making a prediction that may be proved true or false (true in the case of scientific law). It is not prediction that separates scientific law from scientific theory. It is observability and repeatability.
quote:
It is a very good theory because what it predicts has been shown in every single fossil discovered and in the anatomy of every living being on the planet.
It is actually a very bad theory in its current form as it selectively ignores a preponderance of data. To give a few examples: The fact that measurable levels of carbon14 has been found in fossils that are supposed to be hundreds of million years old. The fact that the supposedly immutable radio radiometric dating methods result in vastly different aging for rocks that should be similarly aged in the grand canyon. The fact that the criteria Darwin himself proposed by which the theory of evolution could be contradicted was actually observed in several places (I'll mention the Flagella). These are just a few of the holes in the Theory of Evolution. Nonetheless, the strength of a scientific theory is measured by its ability to make falsifiable predictions with respect to the phenomena it tries to explain. The fact remains that competing theories fail in regards to making falsifiable predictions with which they may be tested.


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