March 29, 2007 11:17
One More Scientific "Truth" Bites the Dust
We all know—I've written it a dozen times myself, and the textbooks all agree—that the extinction of the dinosaurs paved the way for the rise of mammals. With a whole bunch of ecological niches suddenly empty, our whimpering shrew-like ancestors (OK, maybe they didn't whimper, but gives you a feel for their utter insignificance) went through a burst of evolutionary innovation that led, to elephants, whales, Chihuahuas and us.
It's highly—but a paper published in today's Nature says it's probably wrong, or at least way oversimplified. Using both fossil and DNA evidence to assemble an evolutionary tree whose fruit is about 4,500 of the 4,554 known mammalian species, scientists have shown that the many of the primary groups mammals divide into, including primates and rodents, were already present at least 20 million years before the dinosaurs went bust. So the innovation was already happening long before the event we thought (until yesterday) triggered it.
Not only that: the real flowering of these groups into the thousands of species we know of today didn't happen until millions of years after the dinos were gone—so their demise doesn't explain that one either.
I'm a big proponent of the conventional wisdom in science, which sometimes makes me the target of cranks with supposedly brilliant theories. But watching the conventional wisdom demolished is among my favorite things, when it's done well.
March 23, 2007 6:52
France Comes Clean on UFOs!
Plenty of people are convinced the world's governments are conspiring in a massive coverup of the "fact" that UFOs have been visiting our planet for years. In the U.S., for example, it's just obvious that a saucer crashed in Roswell, N.M. in 1947, and that government agents came and removed the little alien bodies. They're still on ice in a secret government lab. Oh, and we reverse-engineered a crashed saucer to discover alien technology too. You think the transistor was invented at Bell Labs, don't you. Ha!
The strongest evidence for all this is that there is no evidence. Naturally--because the government's files on UFOs are still mostly classified. Why would they be secret if there were no actual aliens? Answer me that!
But now the French are coming clean: their government has now released all of its secret UFO documents and put them up on the web. The site has proven so popular that you can't even get to it.
Hmmm......sounds like a conspiracy to me.
March 23, 2007 8:55
The Oz Effect
I refer to the scene in "The Wizard of Oz" where Dorothy wakes up after the tornado to find that she's in Oz--and that the world has suddenly transformed from black-and-white to color. It's how I imagine it would be for me have my red-green color blindness "cured," and to see the world as those with normal color vision do.
It's not that I see in black and white, mind you--that's a myth I have to confront all the time. The way it works is that people with normal vision have three sets of light-sensing cells in their retinas, each one sensitive to a particular color of light. Your brain takes the inputs from all three and calculates what color something actually is. (Which means, by the way, that none of us actually sees color--we see a simulation, manufactured in our brains).
But I have only two kinds of cell, so while my brain creates color too, it's from fewer inputs, so I have a more limited range. So, it turns out, do mice. But now a team of scientists from Johns Hopkins and the University of California, Santa Barbara, have created a line of mice genetically engineered to have three sets of receptors, not two. So like Dorothy, they can suddenly see the world in more vivid color.
They don't quite get the Oz effect, though; they're born with the un-mouselike color receptors. Which kind of saddens me. Because if the scientists had somehow managed to put new color receptors into mice who were already alive--gene therapy rather than genetic engineering--there's a chance they could do it for me too.
It's not that I feel a lack, because I literally cannot imagine what it would be like to see color as others do. How could I? But I'd sure like to experience it.
For a more detailed blog entry on this, go here.
March 22, 2007 2:25
Scott Atran replies
(he replied in a comment, but you might not have read it).
After reading this very thoughtful (but long) reply, I don't think we actually disagree even a little bit.
Dear Michael Lemonick,
I appreciate your trying to get things right. But I still do not understand what you are objecting to, and it may just be my own confusion about what you are trying to say. But let me try to be clear about what I think (as opposed to what I am reported to think).
There can’t be individual fitness advantages of the sort that part-for-whole sacrifice among animals may convey, given that the probability of certifiably obtaining the desired outcome, such as a rewarding afterlife or freedom from catastrophe, ranges between zero and chance. For a bear to sacrifice its paw in a bear trap by gnawing it off, a lizard to leave behind its tail for a predator, or a bee to die by stinging an intruder to save the hive, seem reasonable tradeoffs for survival. Yet, what could be the calculated gain from
- Years of toil to build gigantic structures that house only dead bones (Egyptian, Mesoamerican and Cambodian pyramids)?
- Giving up one’s sheep (Hebrews) or camels (Bedouin) or cows (Nuer of Sudan) or chickens (Highland Maya) or pigs (Melanesian tribes, Ancient Greeks), or buffaloes (South Indian tribes)?
- Dispatching wives when husbands die (Hindus, Inca, Solomon Islanders)?
- Slaying one’s own healthy and desired offspring (the first born of Phoenicia and Carthage, Pawnee and Iroquois maidens, Inca and Postclassic Maya boys and girls, children of South India’s tribal Lambadi, adolescents in contemporary satanic cults)?
- Chopping off a finger for dead warriors or relatives (Dani of New Guinea, Crow and other American Plains Indians)?
- Burning your house and all other possessions for a family member drowned, crushed by a tree, or killed by a tiger (Nāga tribes of Assam)?
- Knocking out one’s own teeth (Australian aboriginals)?
- Making elaborate but evanescent sand designs (Navajo, tribes of Central Australia)?
- Giving up one’s life to keep Fridays (Muslims) or Saturdays (Jews) or Sundays (Christians) holy?
- Or from just stopping whatever one is doing to murmur often incomprehensible words while gesticulating several times a day?
As Bill Gates aptly surmised, “Just in terms of allocation of time resources, religion is not very efficient. There’s a lot more I could be doing on a Sunday morning.”
Functionalist arguments, including adaptationist accounts, usually attempt to offset the apparent functional disadvantages of religion with even greater functional advantages. There are many different and even contrary explanations for why religion exists in terms of beneficial functions served. These include functions of social (bolstering group solidarity, group competition), economic (sustaining public goods, surplus production), political (mass opiate, rebellion’s stimulant), intellectual (e.g., explain mysteries, encourage credulity), health and well being (increase life expectancy, accept death), and emotional (terrorizing, allaying anxiety) utility. Many of these functions have obtained in one cultural context or another; yet all also have been true of cultural phenomena besides religion. For Marx, religion was an opiate dolled out by governing elits to suppress the masses; for Martin Luther King religion was a principal means for the downtrodden to throw off the yoke of their oppressors. For John calvin, obedience to authority was obedience to God, however corrupt or malicious authority seemed; Benjamin Franklin wanted the motto of the new American Republic to read “rebellion against tyranny is obedience to God.”
Functional descriptions of religion in given contexts (but never in any context-free way that would amount to a general proposition, scientific or otherwise) often insightfully help to explain how and why given religious beliefs and practices help to provide competitive advantages over other sorts of ideologies and behaviors for cultural survival. Still, these accounts provide little explanatory insight into cognitive selection factors responsible for the ease of acquisition of religious concepts by children, or for the facility with which religious practices and beliefs are transmitted across individuals. They have little to say about which beliefs and practices – all things being equal – are most likely to recur in different cultures and most disposed to cultural variation and elaboration. None predicts the cognitive peculiarities of religion, such as:
Why do agent concepts predominate in religion?
Why do supernatural-agent concepts are culturally universal?
Why are some supernatural agent concepts inherently better candidates for cultural selection than others?
Why is it necessary, and how it is possible, to validate belief in supernatural agent concepts that are logically and factually inscrutable?
How is it possible to prevent people from deciding that the existing moral order is simply wrong or arbitrary and from defecting from the social consensus through denial, dismissal or deception?
This argument does not entail that religious beliefs and practices cannot perform social functions, or that the successful performance of such functions does not contribute to the survival and spread of religious traditions.
Indeed, there is substantial evidence that religious beliefs and practices often alleviate potentially dysfunctional stress and anxiety) and maintain social cohesion in the face of real or perceived conflict. It does imply that social functions are not phylogenetically responsible for the cognitive structure and cultural recurrence of religion.
What little scientific evidence there is does seem to indicate that several different cognitive faculties are jointly responsible for waht we commonly recognize as religion but which did not evolve specifically for religion or for any individual or social benefit in particular.
Cheers again, Scott Atran
March 22, 2007 1:28
A Plea to Readers
You've all been great about making comments on various posts (some admittedly a little friendlier than others, but it's all good).
Now I'd like to challenge you a bit further. How about letting me know about topics YOU want to see me post on. I've gotten some of my best blog ideas from people I know--my daughter pointed me toward this one, for example, and one of my students at Princeton alerted me to this.
So you see I'm open to suggestion. Let's have some.
March 20, 2007 1:06
More on the Evolution of Faith
Last week I posted this on an article in the New York Times Magazine on the idea that a propensity for religious belief might have evolved.
I've now gotten a comment from the subject of that piece. Scott Atran, a scientist at the University of Michigan. He says:
"You write that I favor the "idea that humanity’s tendency to believe comes from some sort of adaptation in brain architecture tens of thousands of years ago (or more) that helped us survive, somehow."
This is precisely what I do not think to be the case. Religion is no particular adaptation in any interesting sense.
I think that most adaptationist accounts are "just-so" stories - much like the stories of Dr. Pangloss in Voltaire's Candide who argued that noses were made to wear spectacles and legs for britches.
Nevertheless, I think that your separation of "culture" from "evolution" makes no sense. Either human cultural phenomena belongs in the class of unicorns or it has a natural origin. The only natural origins science is aware of are biological, chemical and physical. And all aspects of life, human or otherwise, have only evolutionary processes as a natural origin (including chemical and physical processes).
Cheers, Scott Atran"
I appreciate the comment, and I apologize if I misread his research. Evidently, readers of the article in the N.Y. Times did too, judging from these letters. But there's always a danger of confusion when a scientists' views are seen through the lens of a journalist, so I do apologize.
And of course Dr. Atran is right that at the root, everything we are came about due to evolution. But at a deeper level, everything we are ultimately came about due to physics--yet we don't rush to a physics text when we come down with a cold. My point being that while the development of culture is a consequence of evolution, it didn't necessarily evolve per se, as a biological feature.
But here's a question. In the article, Robin Henig charactizes you as thinking "Religion seemed to use up physical and mental resources without an obvious benefit for survival." This seems to contradict what Dr. Atran says above--it seems to suggest he sees religion as a behavior subject to evolutionary pressure. Whether or not he does, I disagree with the quoted sentiment profoundly. Religion has some pretty clear benefits in calming and comforting individuals and in reducing stress. It also has some pretty clear benefits for unifying and organizing society. This is the case whether or not God exists.
M.L.
March 14, 2007 2:54
Giant Lake on Saturn's Moon
Just a month or two ago, NASA announced that the Cassini spacecraft had at last spotted lakes on Saturn's moon Titan. They're presumably filled with liquid methane and ethane, not water, which freezes hard as a rock in Titan's frigid temperatures—and they're needed to explain why the huge moon has an atmosphere. Without something to evaporate from the surface, Titan's shroud of methane would long ago have disappeared.
But now Cassini's handlers have spotted something so big it's being dubbed a sea, not a lake. Here's more information, plus images.
March 14, 2007 2:00
Cosmic Crash
Remember last summer when Pluto was dethroned as a planet? Of course you do--it was pretty inconsequential a scientific matter, but got as much press as "Britney Goes to Rehab."
What really kick-started it all was the discovery by Michael Brown at Caltech of an object, now known as Eris, that was a bit bigger than Pluto. If Pluto was a planet, Eris had to be too. If Eris wasn't, Pluto obviously wasn't either.
But Brown has found objects besides Eris, and today he and his group have published a paper in Nature that tries to explain the weird object known for now as 2006 EL61, a rapidly-spinning, approximately football-shaped thing as big as Pluto in its long dimension. Brown also discovered that 2006 EL61 has a couple of moons, and now there's a plausible explanation for the whole collection: around 4.5 billion years ago, at around the time Earth was forming, a Pluto-size object was smashed into by something a little smaller. The result: some fragments flew off into space while some continued on more or less together—the moons, and an especially big piece, sent into such a dizzying spin by the impact that centrifugal forces stretched it into a football.
March 12, 2007 11:48
Using a Cell Phone Won't Kill the Patient
If you've ever been in a hospital, you've seen the sign: Cell Phone Use Prohibited. Maybe even with the international no-cellphone symbol—you know, a red circle with a cell inside and a red slash across it.
The reason is that, just as with planes, there's a fear that the radio signals coming from a phone could disrupt the electronics of medical devices like EKGs or other patient monitors. Potentially very dangerous if true.
Not, however, true, according to a new study in the Mayo Clinic Proceedings. Key statement: "The incidence of clinically important interference was 0%"
What the study did not test: does using cell phones in patient areas annoy everyone else around you to the point of homicidal tendencies.
March 10, 2007 8:05
What Nobody Seems to Remember about Daylight Saving Time
I heard them talk about it on NPR. I think I saw them talk about it PBS (am I betraying something about myself here?). Yet for all the fretting and hand-wringing and wacky stories (one on the radio was about Arizona, and how that state's refusal to go along makes for all sorts of strangeness), and all the argument over whether it does or doesn't save energy, and over whether it will or won't lead to a mini-Y2K, nobody I heard or saw bothered to mention the reason so many people love it.
The sun stays up later. It's light well into the evening. Remember? When I talk to my writing students at Princeton, one of the basic rules I try to instill in them is not to leave out an excruciatingly obvious point. Yet everyone I heard talking about daylight saving time this week did just that. I tell the students not to do it because it will make them seem clueless. Which is just what happened with all of those supposed professionals.
I know the arguments against shifting the time of sunrise and sunset--it also stays dark later into the morning, which is bad for kids going to school. But people mentioned that in the stories I heard. And I know that the reason Congress made the shift was to save energy--the same motivation for extending daylight saving time back in the 1970s. Maybe it doesn't really save energy. Maybe it does.
But it stays light later. Most of the people I know think that's really nice, and are quite happy that this will now be happening earlier And now, finally, someone has mentioned it.
You're welcome.
March 9, 2007 11:24
Go to Sleep and Smell the Roses
As a science journalist, I spend a lot of time writing about how much we've learned about one aspect or another of the physical world--but not so much writing about the very basic things we don't know. We don't know, for example, what the universe is made of (aside from the paltry few percent that makes up the stars, planets and everything we can actually see). We don't know how life began (which is not to suggest that I'm a supporter of "intelligent design," in case anyone thought otherwise).
And we don't know what the purpose of sleep is. It's got to be vitally important; otherwise, the evolutionary downside (being unconscious makes it harder to notice that saber-toothed tiger sneaking up on you) would have weeded it out long ago.
One popular theory is that sleep is mainly for helping us consolidate and form memories—definitely important, since our ability to learn and plan for the future is what really sets us apart from other animals. And a new study published today in Science supports that idea. Neuroscientists had volunteers play a memory-based card game while exposed to the scent of roses. Then they exposed some of the subjects to that smell again, while they were in the deepest stages of sleep—and those volunteers remembered more the next day than others who got the second blast of rose scent while in other stages of sleep, or while still awake.
Case closed? Not quite. The improvement in performance was modest, with the properly timed smellers getting 97% of the cards right the next day, but the improper ones getting a decent 86%. Moreover, other recent studies have provided evidence that deep sleep is actually valuable for weakening, not strengthening the connections between neurons (those connections are what memories are made of). So sleep could be as much for clearing the brain of clutter as for memory-making. Or it could be for detecting patterns in what we've learned (other research points to this) so we can generalize and predict the future. And that's just deep sleep; REM sleep, where we do much of our dreaming, may have more to do with remembering motor skills than facts.
But none of this is definitive. All these ideas could be true at once—there's no reason, after all, that sleep has to be "for" any one thing. Conversely, there's equally no reason to be certain that it's not for one main function, with memory and learning tacked on as an afterthought, but that we don't yet know what that function is.
In any case, I celebrate our ignorance about such a fundamental part of human experience. Because it always gives me something new to write about.
March 8, 2007 3:00
Pluto is a Planet After All!
March 8, 2007 11:40
An Encounter with Freeman Dyson
One of the great things about living in a town like Princeton is that some of the world's most creative thinkers work here--and others come to visit all the time. One of the former is Freeman Dyson, a physicist and mathematician of enormous accomplishment. He's been at the Institute for Advanced Study (NOT part of Princeton University, as many people still fail to realize) for more than 50 years, where he used to hang out with Einstein, among other legendary figures. Among many, many other things, Dyson helped establish the field of quantum electrodynamics (everyone agrees he deserved a Nobel for that one), worked on the idea of spaceships powered by nuclear bombs (they even made made a non-nuclear prototype) and proposed the futuristic notion that advanced civilizations would enclose entire stars within a shell to tap their energy fully ("Dyson Spheres" are now a staple of science fiction--but searchers for Extraterrestrial Intelligence have actually looked for them).
All of which earns him the right to speculate freely and iconoclastically on the future, which is what he did last night at a small dinner at Forbes College on the Princeton campus. Dyson, it turns out, isn't too worried about global warming or the dangers of genetic engineering. The time frame for the former is long enough, the believes, that technology will figure out ways of dealing with it long before it's a problem. And while others focus on the potential horrors of genetic engineering, Dyson's take focused more on the Philadelphia Flower Show, now going on, on a reptile show he attended recently in San Diego with his grandchildren. Flower growers have already produced an astonishing variety of blooms through old fashioned breeding and hybridization; why, he argued, shouldn't the result of genetic engineering being even more beautiful flowers rather than strange new creatures?
And why shouldn't even the latter be something to look forward to? "The problem for a grandparent at a reptile show," he said, "Is how do you get a kid out of the show without buying a snake. Just imagine the kinds of lovely monsters you might create."
It isn't that Dyson is a complete Pollyana about technology; it is, rather, that he's seen grandiose predictions in the past. Back in the late 40's, the great mathematician John Von Neumann built one of the earliest electronic computers, and his assumption was that computers would become bigger and more expensive over the years. How many would the country eventually have, someone asked him? Eighteen was the answer.
The other good thing about Princeton is that when someone like Dyson speaks, lots of other very smart people, from students on up, come to listen--and they're not shy about challenging even such an eminent scientist. Unfortunately, I had to duck out on the very lively question-and-answer period; I was due to judge the Latke vs. Hamantaschen debate across campus.
March 7, 2007 1:46
Is Atkins Best?
Diet mongers are in a tizzy over a study that appeared yesterday in the Journal of the American Medical Association. Scientists at Stanford reported that they'd randomly assigned 311 overweight, premenopausal women to one of four diets: Atkins, the Zone, the Ornish ultra-low-fat diet and something called the Lifestyle, Exercise, Attitudes, Relationships and Nutrition (LEARN) diet, based on U.S. government guidelines (anyone ever heard of this?).
Anyway, after a year the Atkins women had lost more weight (about 10 lb. on average) than the next best (just under 6 lb.), and had better cholesterol and blood pressure readings to boot.
All of which means...well, possibly not much at all, except that Atkins isn't as awful for you as some experts have thought. For one thing, the dieters weren't monitored to see how well they actually followed each diet. For another, premenopausal women don't tell you much about postmenopausal women or about men. For another, the difference between 5 and 10 lb. isn't huge--and besides, pretty much any diet well help you lose weight. The hard part, as everyone should know by now, is keeping it off. Even the study's author, Christopher Gardner, told the Associated Press that Atkins ''isn't the solution for the obesity problem."
Gardner also expressed concern that these results would be overinterpreted. He must be new in town.
March 6, 2007 8:36
Is Religious Belief the Result of Evolution?
Some regular visitors here probably think I swallow every idea that comes from evolutionary biology uncritically; if it has “evolution” in the title, it must be good.
Not so. For the past several days, I’ve been engaged in an online debate with my colleagues at the National Association of Science writers over this story in the New York Times Magazine last Sunday. It’s about an anthropologist named Scott Atran who is investigating the evolutionary roots of religious belief—the idea that humanity’s tendency to believe comes from some sort of adaptation in brain architecture tens of thousands of years ago (or more) that helped us survive, somehow. It is, writes the author, Robin Marantz Henig, “ something few people were doing back in the ’80s. Today, the effort has gained momentum, as scientists search for an evolutionary explanation for why belief in God exists…”
I don’t buy it. I do lean strongly toward the belief that religion is an aspect of human culture, not a glimpse into the divine—but I don’t understand, and Henig doesn’t really address, why it should be singled out and slapped with the requirement that it be explained by evolution. What’s next—the evolutionary basis for our liking theater (most cultures have it in one form or another)? Or sports?
Obviously, some of our preferences almost certainly did evolve. We universally like sweet and fatty foods, for example; that’s because they’re the most energy-rich, and held the most survival value for early humans. We universally like sex. And our minds have certainly evolved to solve complex problems.
But the idea of something as specific as religious belief requiring an evolutionary explanation just seems excessive to me. The principle known as Occam’s Razor suggests you shouldn’t go looking for unnecessary hypotheses. The evolution of religious belief, I argue, is one.
March 5, 2007 8:50
An Explanation for Premature Puberty?
When I wrote this cover story on the disturbing trend toward earlier puberty in American girls, there was no clear explanation for why it was happening. The trend mostly involves the development of secondary sexual characteristics (pubic hair, breasts) more than early menstruation. But opinions ranged all over the place about the reason, from hormone-like chemicals in pesticides washing into the water supply to hormones in beef to obesity in young girls.
Now the obesity theory has gotten a boost: writing in the journal Pediatrics, a team of physicians from the University of Michigan looked 354 girls, some as young as 3, and found that a higher than average body mass index is associated with premature breast development. Since early puberty can lead to all sorts of problems, including premature sexuality, drug abuse and a higher incidence of reproductive cancers later in life. it's just one more reason to watch out for obesity in kids.
March 1, 2007 3:25
Saturn Like You've Never Seen it
This astonishing photo shows the planet Saturn from above, as seen by the Cassini spacecraft (it's the one that dropped a lander, called Huygens, to the surface of Titan a couple of years ago). The planet itself is washed-out because of the long exposure required to show the rings in their glory. No breakthrough science here; just a moment of inspiration.
About Eye On Science
TIME contributing writer Michael D. Lemonick fills you in on what's hot, what's cool, what's controversial and what's just plain silly in the world of science. Comments encouraged.
RSS Feed
 |
Daily Email
Recent Posts
Eye On Science Archives
July 2008
Choose a day to view events.
<< Previous Months
| 1 | 2 | 3 | 4 | 5 | ||
| 6 | 7 | 8 | 9 | 10 | 11 | 12 |
| 13 | 14 | 15 | 16 | 17 | 18 | 19 |
| 20 | 21 | 22 | 23 | 24 | 25 | 26 |
| 27 | 28 | 29 | 30 | 31 |