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

[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

[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

[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

[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

[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?

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

[poly_pusher]

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