Slashdot videos: Now with more Slashdot!
We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).
OTOH, people are clever. I'm open to someone coming up with an interesting statistical approach that proves me wrong for these deep coalescenceses.
This means even in the relatively recent past, the amount of DNA we're looking at is pretty dang tiny. Part of the reason ancient DNA is so dang tricky is because the much of what you sequence is not actually what you're interested in - doubly so when you're sequencing something closely related to humans. For example, did some spot sequencing of ancient/historic polar bear remains, and had to toss out a chunk of the data we got back, as it was soil bacteria(/fungi/pollen) contamination. How do we know which is which? We had good scaffolds to align our bear sequences back up again, though not everyone is as fortunate as us.
In addition to being rare, what is left is fairly short. You can imagine if you start putting breaks in at random, your average length is going to start declining rapidly, and then level out at some small value that takes quite a while to get smaller. It'll get there, and given geologic time scales, a lot of what we want is that far back, but it'll take a while.
Finally, what isn't mentioned in this summary is that there was massive variance in the estimates of half-life. Supposedly only 40% of the variance in halflife was explained by age. Preservation, inter-lab differences, and good old fashioned luck probably contribute considerably to variance in half-life.
There are other factors too, but they're boring, and I should probably get work done instead of dragging out this reply.
(And to answer your latter question, Neanderthals have been sequenced whole genome, not just mtDNA).
I'm fairly underwhelmed with it. First is the issue you mention of "how many negative results did he not publish?" that is rather insidious. Then there's all the issues that come from his small data set size, and the fact that he did not use large portions of his actual data. And can't be bothered to report it. Or provide it. But it just wasn't useful data, for reasons not explained. I wouldn't accuse the authors of misconduct (no doubt the authors believe their ms is true), but the practices described is definitely a great way to get a false positive. Briefly skimming the interwebs show other people have some statistical issues with this too. http://www.science20.com/science_20/blog/gm_maize_causes_tumors_rats_here_how_experts_responded-94259
Sadly, only "GM crops evil!" will get reported, because it plays into a social narrative. Not "shitty stats continues to be shitty!"
If you asked a homeopath, though, the ultra-rare nature of the pollutant is what makes it especially deadly. Heaven help us if the mercury in the water become any more dilute, we'll all die from its toxicity.
And in any event, any analytically chemist would tell you that in many regulations out there, we set unrealistically low requirements for some contaminants. Sometimes its because water naturally has a lot of junk in it, and getting it out on a utility scale is tricky, but more often than not, the 'safe levels' are picked as arbitrarily low numbers by middle manager types without any understanding that the analytical methods for detecting the analyte of interest at that low of a level aren't feasible.
There's an adage about wrestling pigs from Shaw that's relevant to this.
It's hard not to be personally insulted in such a case. Hell. I'm starting to feel more than a touch offended on his behalf. I know in such a case, even if there was nothing I had ever written that could be misconstrued, I would fight bitterly and with all my reserves to thwart such an attack on purely personal grounds. As someone on slashdot, I'm surprised you don't realize that sometimes people fight even losing battles purely on principle.
At its root, the only things that really 'exist' are probably genes, which struggle for existence in communities of other genes, trying to replicate themselves as much as possible because the ones who don't aren't around anymore. But working purely with genes, and nothing else, needlessly complicates a great many things.
I'm comfortable with that dimensional analysis. Easy peezy. I'm less sure about the power consumption of warning: 20 seconds at 35 watts (A typical DVD player) would be 700 watt seconds. That times 147 million would come out to around 28.58 Megawatt Hours a year. That seems a bit much, though, so I may have made a mistake there. The average home supposedly uses around 11 megawatt hours a year. At 11 cents a kw/hr, that's 3,144.16666 dollars.
Now I'm not sure how to price leisure time, but I think the right economic thing to do would be to assume it's worth greater than or equal to the alternative activity (earning whatever per hour). I don't know what that number is, so I'm just going to assume it's a buck fifty arbitrarily. I don't think I could find many people to sit willing to sit being bored for 1.50 an hour, but I don't have time to dig through the lit to find a better one. At 1.50 an hour, the 20 seconds waste around 1.22 Million Dollars a year. which is a fair bit than the 3.1 Thousand dollars wasted electricity.
For those who must know, 93.27 years is 0.000213 Library of Congress equivalents, assuming you can read one book a week.
I think you're being unfair with the money begging. Basically, here's what they'd said (by my reading): Fusion power is going to happen. It's a matter of when, not if. But if we want it in a timeframe that most humans are used to working (before most of us are dead and buried) we need to start taking it seriously. Insert allusions to the Manhattan Project and the Apollo Missions, both of which involved pouring a ton of money into a specific scientific problem.
I'm pretty disappointed they didn't talk more about the NIF. Pretty much every article I read about "Yet another fusion problem solved; thinks rosier than we thought!" has been work coming out of the NIF.
I try not to think with my gut. If I'm serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble. Really, it's okay to reserve judgment until the evidence is in.
I don't know enough, for and against, to make a reasonable decision. And I'm not in a position to effect change, even if I had an opinion. I think it's better for me to leave the debate to the real experts, instead of trying to prognosticate from my armchair. It's a crazy idea. It just might work.
That'd be nice. I wouldn't have to work. I could just play video games and play with robots forever.
That would be nice. Except it's entirely untrue. And there is money, it's not 3k, and it's not for `simply living there.` It's royalties on oil money and rent, which instead of directly being plugged back into education, or whatever, the state decided to let people spend as they see fit. The amount doesn't even cover cost of living, which is incredibly high due to logistics.
Everytime I'm in Anchorage, I go to the Bear Tooth, because it doesn't matter what movie is showing, it's worth it for the experience of seeing a movie like that.