Did a Genome Copying Mistake Lead To Human Intelligence?

A new study suggests that the sophistication of the human brain may be due to a mistake in cell division long ago. From the article: "A copyediting error appears to be responsible for critical features of the human brain that distinguish us from our closest primate kin, new research finds. When tested out in mice, researchers found this 'error' caused the rodents' brain cells to move into place faster and enabled more connections between brain cells."

Comments

Evolution

[Anonymous Coward]

Isnt this the whole point of evolution?

Re:Evolution

[Intrepid imaginaut]

Maybe the discovery is the exact mechanism which prompts the rise of higher intelligence? Intelligent animals anyone?

Re:Evolution

[dBLiSS]

Agreed. The use of the word "mistake" implies that there was some sort of intelligence designing the genome and it make a mistake. This just sounds like "random mutation + natural selection = evolution". No need to call it a "mistake"

Re:Evolution

[SJHillman]

The only "point" of evolution is survival. Evolution does not lead towards more intelligent creatures unless intelligence itself better ensures survival. There are many cases of evolution leading to simpler or dumber creatures that have other traits that give them an edge in their environment. It's not a thinking, planning system.

Re:Evolution

[fuzzyfuzzyfungus]

There is a pretty significant difference between the (well supported but rather vague) hypothesis that human intelligence is the result of some mutation(s) in our evolutionary history and a hypothesis about a specific mutation, of a specific type(there are a number of distinct types of copying errors that tend to occur, and obviously plenty of different locations for them to occur within the genome), with a demonstration that that particular tweak makes for a notable change in the neurons of an animal model...

Re:Evolution

[FunkDup]

It's a particlar kind of copy/write error that leads to another process. From TFA:

One type of error is duplication, when the DNA-copying machinery accidentally copies a section of the genome twice. The second copy can be changed in future copies — gaining mutations or losing parts. The researchers scanned the human genome for these duplications, and found that many of them seem to play a role in the developing brain.
[...]
An extra copy of a gene gives evolution something to work with: Like modeling clay, this gene isn't essential like the original copy, so changes can be made to it without damaging the resulting organism.

Re:Evolution

[Anonymous Coward]

Way to miss the point completely.

Re:Evolution

[Anonymous Coward]

Oh it's not *that* hard to come up with a scenario of some kind, if you really have to believe for some reason.

Some people call these copy errors a "bug", God calls it a "feature". Add a dash of natural selection, and you've got a self-maintaining and self-optimizing system for life to diversify and adapt. None of this having to re-create a whole bunch of things when extinction happens. We're talking low maintenance. The "lazy man's" creation. Like a garden that grows and trims itself. Beautiful really.

But if you mean a scheme where God says *poof* and life is created perfectly all at once, yeah, that's utterly ridiculous. Like believing in a flat Earth or phlogiston.

Re:Evolution

[DThorne]

Actually, there is a pretty good reason to call it a 'mistake'. You get more press.

Re:Evolution

[Pollardito]

It's a mistake because an error was made in the process of transcribing genes between DNA strands. The mechanism failed in its task, no matter whether that mechanism itself was designed or evolved

Re:Evolution

[AliasMarlowe]

Animals are already at the level of Ted Haggard, Jerry Fallwell, Creationists et al..

Animals without a central nervous system are not bothered by this remark.
Animals with single-digit IQs suspect you've just insulted their intelligence.
Animals with an IQ or 10 or more are certain of it, and they're utterly livid.

Re:Evolution

[ideonexus]

I think Richard Dawkins made it okay to use these quasi-anthropomorphic terms to describe processes of evolution when he titled his book "The Selfish Gene," so long as you constantly remind people, as he does laboriously in his text, that genes do not have wants, intentions, or consciously-implemented strategies. It's like saying photons are both a wave and a particle, I've read many physicists who point out that we use the wave-particle duality as a means of conceptualizing something so alien to our macro-reality into something we can understand so the non-expert can enjoy the wonder as well. So too do we attribute all sorts of human concepts to the algorithm of natural selection to make it easier to understand.

Still, your criticism is a valid one and something people need to be reminded that we are talking about inanimate processes.

Something that occurred to me reading the article was that when I saw the term "cell division" I immediately pictured a developing embryo, but that would be a somatic mutation rather than a germinal mutation. It's important to remember that all these evolutionary mutations didn't happen in the animals, they happened in the animals' gametes, the sperm and eggs. A mutation that occurs in the cell division of a developing embryo wouldn't have any affect on the individual's gametes, the mutation had to occur in the sperm or egg first.

Re:Evolution

[Ferzerp]

Well, not exactly. Copying mistake suggests a meiosis or mitosis failure. However, there is also the potential for DNA to be altered and then copied accurately.

Re:Evolution

[Jappus]

You seem to have heard that our improved understanding of genetics and other details of inheritance mean that Darwin's ideas have to be flawed because they did not yet contain this understanding; much like Newton's theories were supplanted by Einstein's and his in turn by parts of Quantum Theory.

But this is neither strictly not loosely true. Newton's theories are flawed, because they indeed overlooked an integral property of physical reality. Its formulas simply lead to values that are not correct in our universe. But, and here's the important difference to Darwin's theory of Natural Selection: Darwin never stated any formulas leading to precise predictions. He never explained the principle driving the changes needed by Natural Selection.

What he did was more subtle. He looked at the world and identified the obvious end-result: Species change, compete, cause their predecessors to perish (or change) and then finally perish themselves. Species are not static and unchanging. Instead, each organism is different from the one it sprung forth from. Given enough time, these subtle changes lead to large differences; so large that you'd not immediately see that they are related.

As such, Darwin's point was that Variations, Families, Races and Species are just "grouping terms". They fluidly flow into each other. Small individual changes lead to large cross-species differences.

This point is clearly not flawed. It is quite obviously true, if you look at the historical record and current progress. And that is his entire theory. He never stated what the principle behind the system was, as he could only suspect, not prove. This, he left for later generations. He freely admitted that, if no such system could be found, that his theory would have a huge problem. Thankfully, modern biological sciences has found this principle in all its differentiated glory from genetics, epigenetics, vertical and horizontal inheritance, retro-viral modification, genetic absorption, etc. pp. So instead of not accepting his model, they actually and knowingly vindicated it!

Of course, some of Darwin's larger speculations turned out to be wrong, but these were not the core of his theory of Natural Selection and clearly labeled by him as pretty much unsubstantiated speculation. Just go ahead and read "The Origin of Species" and you will see how careful Darwin was by stating exactly what could break his actual theories' back, which points he though could be proven beyond doubt and which are more doubtful.

So, tl;dr: His theory is actually vindicated by modern science; but it's not the theory of evolution but the theory of natural selection, as these two are quite distinct beasts.

Re:Evolution

[msauve]

"The only "point" of evolution is survival."

No, the only point of evolution is successful reproduction. It makes no difference how long you survive. If your genes aren't passed to offspring, any evolutionary change you may have had dies with you. Likewise, it makes no difference if you die after producing self-sustaining offspring - your contribution to the gene pool carries on.

Re:Evolution

[InsertCleverUsername]

The only "point" of evolution is survival. Evolution does not lead towards more intelligent creatures unless intelligence itself better ensures survival.

Exactly. This is the thing that always puzzles me about many people's pondering of extraterrestrial life. No doubt there's plenty of it out there --nothing about that seems very unlikely, but there doesn't seem to be any overwhelming requirement for sentient intelligence. Look what a good run the dinosaurs had without understanding how to build a fire or use an iPhone. Seems like the best meeting of Drake and Occam, IMHO.

Re:Evolution

[fuzzyfuzzyfungus]

A cynical observer noting the noble progress of technology in service of the defense industries might say the same of humans, only dumber and less cute...

Re:Evolution

[camperdave]

"The only "point" of evolution is survival." No, the only point of evolution is successful reproduction.

No, there is no point to evolution. It is simply a side effect of an imperfectly self replicating system (such as amino acid chemistry) in an environment that is non homogeneous.

Re:Evolution

[RDW]

The subtitle also has a stylistic difference from the article text--it has no comma or other punctuation. Every sentence of comparable length in the rest of the article (around 15 of them) has a comma, colon, dash, etc., with only one exception, supporting my "someone else wrote the title and subtitle" theory, perhaps someone more interested in page views than providing information.

This is why I love Slashdot - we'd rather spend ages analysing a secondary popular science article to death than talking about the interesting findings of the primary research! The author and/or editor deserve a break for trying to engage the attention of a general audience about a piece of significant work, and succeed in presenting the key points in relatively non-technical language. Both 'mistake' and 'error' are in any case used quite frequently by biologists when discussing mutations - a quick pubmed search will find many examples in the scientific literature (e.g. http://www.ncbi.nlm.nih.gov/pubmed/14616055 - this does not imply that the DNA polymerase is intelligent!).

Speaking of 'mistakes', this research discovered an interesting error in the human genome reference sequence. It turns out that the duplication event was previously obscured by 'mis-assembly' of the closely related copied sequences (the SRGAP2 gene was copied so recently in evolutionary terms that the copies hadn't diverged enough to be easily distinguishable). The researchers did some of their own sequencing using DNA from a 'hydatidiform mole' ( http://en.wikipedia.org/wiki/Hydatidiform_mole ), a non-viable pregnancy that only contains genetic material from the father - the lack of confounding allelic variation makes it easier to get clear cut results.

Re:Evolution

[Prune]

I think that is an important point, and it's not so much intelligence per se, but complexity itself. Single-cell organisms are the pinnacle of evolutionary success on Earth, whether measured by biomass, numbers, adaptability, and spread throughout every environmental niche. They're just complex enough to be alive, and not much more. Intracellular processes are far more optimized than the larger scale functions of multicellular organisms--in many cases, certain cellular processes are provably optimal in terms of energy use. This level of optimization on a multicellular organism probably would take longer than the lifetime of most stars.

Beyond this, once sufficient intelligence appears on some world, technology is almost inevitable if the species continues existence long enough (though I imagine some would disagree). The problem with technology is that it magnifies the fundamental asymmetry between the difficulty of creation and ease of destruction. In our own case it is clear that advanced technology enables an ever smaller group to destroy an ever larger portion of people; in the limit, eventually a single person will be able to destroy all of humanity. Reactive protections against such disaster is always at a significant disadvantage and it only has to fail once for all to be lost. The alternative, pervasive monitoring of every individual at all times without exception also brings issues (I mean beyond the ideological issues of freedom), in that it creates a much more highly integrated social system, and large complex systems are prone to catastrophic failure, as discussed, funny enough, in a slashdot article not long ago. I would be surprised if there is still civilization 500 years from now.

Keep in mind the old argument that galactic colonization is an exponential process, as each colony sends out a ship, the expansion rate grows. Even with each colony sending out ships at a fairly low constant rate, say every 500 years, it only takes a few million years to colonize the whole galaxy. Yet this clearly has not happened, even though intelligence would have to have arisen only once. With the two major factors I listed above, I don't think the first one alone is sufficient to decimate the chance of this happening as much. It's more likely than not that, given the sheer number of planets in the galaxy, intelligence has appeared before on occasion. But couple in the second factor, and the likelihood is that no one has made it far into space.

Re:Evolution

[DM9290]

The only thing Darwin missed was a method of heredibility. That is a flaw, no doubt, but as Stephen R. Gould wrote, the overarching theory still works. The Modern Synthesis is just Darwinian selection married to genetics. In other words, both complement the other.

He didn't claim to have found the actual method of inheritability. He didn't miss it, he had no evidence upon which to build a hypothesis and he pointed this out. The word "flaw" is inappropriate. Recognizing the gaps in knowledge that remain after drawing all the conclusions that the evidence suggests, and leaving suggestions to others for future investigation is one of the beauties of science. It is not a flaw.

Isn't that kind of expected?

[YttriumOxide]

Isn't that somewhat the expected process of evolution in general? Genetic mistake happens; proves to actually be useful to reproduction/beating the competition (as opposed to the vast majority that are either useless or detrimental); and then due to being in the most successful breeders, becomes "standard".

Re:Brain

[jaminJay]

I think so, Brain, but how are we going to get the monkeys to wear plastic underpants?

Super-intelligent mice?

[gtvr]

How long until they break out & take over the world?

More proof that copying is BAD!

[erroneus]

Sorry, the articles on copyright and intellectual property still have me spinning a little. Something out there was making genome copies which are not legitimate and the result is there for all to see. If people didn't get so smart, there wouldn't be so much copying going on either.

Okay, okay, more on topic. The crowd is already saying "it's evolution." Okay, let's just get this behind us, "DUH!" Okay, that was short for "yes, they are explaining that evolution led to the changes which produced humans and human intelligence. But you are seeing the forest and forgetting to notice the trees. What aspects and details of human evolution have had striking results? One of many answers is this thing that happened which enabled the brain to grow in complexity and power."

Now that said, there are lots more. I think one of the more interesting details is that our eyes show white in the corners so that other people can see what we are looking at. That's huge in terms of human communication. There are lots of things in human evolution which have led us to where we are today. But if one were to go back to a single thing -- a single point of divergence -- it might be the one in the article.

Re:More proof that copying is BAD!

[dutchwhizzman]

Are you telling me that if you copy bad music often enough, it might turn into good music?

Re:More proof that copying is BAD!

[Hogwash McFly]

Imagine if you had somesimple computer-generated music into which random mutations were introduced. These could be presented to listeners who would decide through an online vote the 'fitness' of the new segment over the original. Any mutations deemed favourable could be recombined into the 'genome' of the track. Would it be possible for a basic track to evolve gradually over time into a complex piece of music that sounds better at each stage?

It's Not a Bug...

[Anonymous Coward]

It's a feature!
.
.
.
I'll get my coat now...

isn't this the start of a movie plot?

[million_monkeys]

scientist 1: "We figured out the secret to human intelligence!"
scientist 2: "Let try it on those animals in the cage and see if we can make them super smart!"
scientist 1: "Good idea! I can't imagine any scenario where that could go wrong."
scientist 1&2: "Yay!"

in the background:
chimp 1: "Pass me some more smart drink"
chimp 2: "You got it buddy. Once we're smart enough to get this cage open, we are so gonna fuck them up..."

Re:Not at all; completely on point

[Quiet_Desperation]

Well, there was that incident over at the NIMH.

Re:Not at all; completely on point

[dragonsomnolent]

shhhh! it's a secret.

Re:Not at all; completely on point

[na1led]

Speech is just a convenient tool that we just happen to have; it could have been some other form of communication. Not every intelligent species in the universe is going to speak.

Re:Not at all; completely on point

[MightyYar]

Got to change them all to get actual speech.

And then on the other side of the coin, you have many birds that quite clearly have the required physiology for human-style speech, but haven't evolved the mental faculties.

Re:Not at all; completely on point

[poly_pusher]

Sorry I just can't resist. You sir are talking out your ass... ;)