I hadn’t realized that Abraham Lincoln and Charles Darwin were born on the same day, exactly two-hundred years ago today. Alan Boyle is covering the bicentennial Darwin week all week. And in honor of the event, Charles Johnson points out a story debunking one of the most common ignorant accusations against evolution — that there are no “transition” fossils.
Category Archives: General Science
Not Just A Theory
Here’s a useful web site for those people who claim that evolution is “only a theory,” an argument that’s so ignorant that it’s not even wrong.
Bailout Questions
Here are some good ones. I suspect that the socialists will have a response to this one, though:
President-elect Obama claims that spending approximately $800 billion will create 3.675 million new jobs. That comes to $217,000 per job. This doesn’t sound like a very good value, especially with the national average salary around $40,000. Wouldn’t it be cheaper to just mail each of these workers a $40,000 check?
The response will be that the jobs will last more than a year. But of course, they’d have to last at least five years to be equivalent.
Syllogism Practice
I scored a hundred percent on this quiz. But remember, it’s a test of deductive, not inductive logic (e.g., ignore whether or not the premises are valid — focus on the validity of the syllogism itself).
[Via Paul Hsieh, who got the same score as I did. Or so he says…]
Thoughts On Extinction
…and scientific paradigm shifts, from A Jacksonian.
[Via Joe Katzman]
The Origin Of Life
An interesting new theory, for those well versed in organic chemistry.
[Update in the afternoon]
This seems related:
Not content with achieving one hallmark of life in the lab, Joyce and Lincoln sought to evolve their molecule by natural selection. They did this by mutating sequences of the RNA building blocks, so that 288 possible ribozymes could be built by mixing and matching different pairs of shorter RNAs.
What came out bore an eerie resemblance to Darwin’s theory of natural selection: a few sequences proved winners, most losers. The victors emerged because they could replicate fastest while surrounded by competition, Joyce says.
“I wouldn’t call these molecules alive,” he cautions. For one, the molecules can evolve only to replicate better. Reproduction may be the strongest – perhaps only – biological urge, yet even simple organisms go about this by more complex means than breakneck division. Bacteria and humans have both evolved the ability to digest lactose, or milk sugar, to ensure their survival, for instance.
Joyce says his team has endowed its molecule with another function, although he will not say what that might be before his findings are published.
More fundamentally, to mimic biology, a molecule must gain new functions on the fly, without laboratory tinkering. Joyce says he has no idea how to clear this hurdle with his team’s RNA molecule. “It doesn’t have open-ended capacity for Darwinian evolution.”
Not yet.
Daisyworld
…meet rainmaking bacteria:
Barbara Nozière of Stockholm University, Sweden, and colleagues suggest that surfactants secreted by many species of bacteria could also influence the weather. While these are normally used to transport nutrients through membranes, the team have shown that they also break down the surface tension of water better than any other substance in nature. This led them to suspect that if the detergent was found in clouds it would stimulate the formation of water droplets.
This is the kind of thing that makes me skeptical about bureaucratic solutions to planetary engineering, natural or otherwise.
Into Arthropods?
Here’s the blog for you. It’s a good guide for IDing creepy crawlies.
[Update a few minutes later]
Not related, and yet it sort of is. How did pterosaurs get into the air?
In The Eye Of The Beholder
The science of attractive faces.
Free Fall
As Clark notes, here is a very nicely written piece on parabolic flight and weightlessness. Rare is the reporter (even science reporters) who get the physics right on this, because (as he points out) they get confused by the phrase “zero gravity,” which doesn’t really exist anywhere in the universe. Only one quibble:
Each period of ‘weightlessness’ is limited to half a minute or so; otherwise we ‘zeronauts’ would continue freefalling right into the Nevada desert at 600mph. As it is, during half-a-minute’s power- dive we drop nearly 20,000ft – although inside the plane we are completely unaware of this.
This gives the impression that weightlessness only occurs when you “drop” (i.e., descend in altitude). But it actually happens on the way up as well. In both cases, you are “falling” (in the sense that there is no force acting on you other than gravity). First you fall up, then hit the top of the trajectory, then fall down, weightless all the while, and unable to discern your direction of motion. If this seems counterintuitive, it is. But consider an elliptical orbit. As you approach perigee you’re heading down (toward the earth), and once you reach it, you start heading back up (away from the earth) to apogee, but you’re in orbit, and free fall the entire orbit. A parabola in an aircraft is an orbit that, if continued, would intersect the earth’s surface (which is why it is wise to not continue it). And of course, to be more technical yet, it is only parabolic in an approximate sense (assuming flat earth). In reality, it is a tiny section of an ellipse, because the contents of the aircraft are (briefly) in orbit, within the atmosphere.
I should also note that the phrase “power dive” is also misleading. “Power dive” implies that you are diving with engines at full thrust to get down as fast as possible, but in fact, the engines are barely running above idle throughout (until the pullout). Their only function is to overcome wind resistance so that the aircraft can approximate a cannon ball falling in vacuum.