The colors of fall

The leaves are falling off the trees pretty quickly here in New England, but only after putting on a fantastic color display this year. I haven't seen blazing foliage like that in a while.

But where do those colors come from? What causes that fiery display? As we all learned in high school biology class, the green we see in the leaves from spring through summer is caused by chlorophyll - the pigment that captures sunlight for photosynthesis. As the temperatures drop and the days get shorter, leaves stop producing chlorophyll. And here's the trick. The orange and yellow pigments, called carotenoids, are already there...the leaf produces them at the same time that it produces the chlorophyll, but they are masked by the intensity of the green coloring. Once the green is gone, the orange and yellow can show through.

As for the reds, they come from pigments called anthocyanins - and these are a little more mysterious. They are only produced in the fall, act as a kind of antifreeze and sunscreen for the leaves, and, interestingly enough, can be a sign of a tree in distress (a tree that turns red early is in some trouble).

In nature, you often find that brilliant colors are a signal for danger or distress. Me, I like to think of these colors as a sign that my favorite season is here.

[Read more at MSNBC.]

When astronomy meets...demolition?

It can be a dangerous world, even if you don't go out your door. Late last month a cottage in western Germany was destroyed by a fire. What made this fire unusual is that it seems to have been caused by a meteroite. Authorities in Siegburg, Germany, baffeled as to how the fire could have started, turned to a nearby observatory for assistance. At the time of the fire, the earth was passing through a field of "meteoroid splinters." Witnesses who saw the fire also reported seeing a "blazing arc of light" in the night sky.

Most meteors don't make it thru the atmosphere, burning up long before reaching the ground. Seems this one didn't. The police think the meteor that destroyed the cottage was no bigger than 10 mm.

[Take a look at Reuters for the original story.]

Imagine all the people

As I write this, the US population is on the verge of breaking 300 million. In fact, the Census Bureau estimates that we'll hit the magic number at 7:46 AM EDT tomorrow morning. The last time the country broke a hundred million mark, it was 1967. (That would be 7 years before I was born.)

While many are taking the opportunity to discuss America's consumption patters, resource usage, and immigration policies, an interesting article showed up on New Scientist today. What would happen to the environment, the world, if the human species just up and left? How long would the traces of human habitation last on the planet?

As you can imagine different aspects of the human footprint would disappear at different rates. It's actually a fascinating study in entropy (roughly, the tendency of a system to go to the least energetic state - to just fall apart - when there's no one to maintain it). There's a couple of ways of looking at this article. First, the glass-half-full argument: that in spite of how much we've done to the planet, none if it is totally irreversible, that if left to its own devices, nature will take care of her own. Then there's the glass-half-empty argument: that it would take 100s to thousands (in the case of nuclear waste, maybe even millions of years) to undo the damage we have done.

You can read into it what you want. Me, I like the idea that things can bounce back. But, if we were to turn everything off right now, would the environment, the ecology turn out exactly the same? No, of course not. The environment probably didn't return to an exact pre-Ice Age state after the glaciers melted, either. Once an ecology is altered, artificially or naturally, I imagine it's nearly impossible to return it to its native state. However, the resilience of nature is amazing. You can see it just by looking at a vacant urban lot, and see the grass, weeds, and trees taking it over. Nature will grow back where it can.

But that doesn't mean we shouldn't still be careful what we do.

[See New Scientist for the global exit story. To see how close the US is to the 300 million mark, see the Census Bureau's population clock. Most likely, by the time you read this, the zeros will have turned over. "Earth at Night" courtesy of NASA's Astronomy Picture of the Day.]

Nobel Prize updates - have you got your scorecard out?

Since my last Nobel prize post, two more of the Nobel prizes for 2006 have been handed out.

On Tuesday, the Nobel Prize in Physics was awarded to John Mather and George Smoot for their efforts to peer into the earliest moments of the universe. Dr. Smoot should not be confused with Oliver Smoot, another MIT alum whose physical stature was the basis for the smoot, a somewhat non-standard unit of measurement.

Wednesday dawned with the announcement that Roger Kornberg had been awarded the Nobel Prize in Chemistry for his work on the mechanisms of genetic translation (the process by which our DNA is decoded into, well, us). Dr. Kornberg follows in the footsteps of his father, Arthur Kornberg, who took home the Nobel Prize in Medicine in 1959; they are the 6th father-and-son laureate pair in the history of the Nobel Prizes.

[More on the Nobel website.]

If Fluffy makes you sneeze...

....then it's time to trade up to a hypoallergenic cat!

For those allergic cat lovers who can't be bothered with antihistamines or allergy injections -- and have about four grand kicking around -- science brings you a new kitty specifically bred to produce less of the protein that makes you red-eyed and and sniffly. The new kitties, created by a research firm called Allerca, were produced by the oldest form of genetic engineering in the book: selective breeding. By finding cats that naturally produce less of the protein (called Fel d1) and breeding them together, Allerca was eventually able to raise cats that don't raise the hackles of our immune systems.

Allerca first started taking orders for the sneeze-less felines back in 2004, and there's already a long waiting list.

[More on the BBC, or on the Allerca website.]

It's like the Oscars, but for academics

The academic world is holding its collective breath, as we've entered the most exciting time of the year...Nobel season. Over the course of the next few days, the Nobel Institute will announce the winners of this year's Nobel Prizes. Awarded by Sweden's Nobel Institute, the Nobel Prizes have been awarded since 1901 for achievements in physics, chemistry, physiology or medicine, literature and for peace.

The awards were established in the will of Alfred Nobel, who, according to the Nobel Prize website, was "a scientist, inventor, entrepreneur, author and pacifist." He also happened to be the man who invented dynamite.

The will said, in part:

The whole of my remaining realizable estate shall be dealt with in the following way: the capital, invested in safe securities by my executors, shall constitute a fund, the interest on which shall be annually distributed in the form of prizes to those who, during the preceding year, shall have conferred the greatest benefit on mankind.

Nobel died in 1896, but the first award was not given until 1901. The reason? His family contested the will. Ahh, sweet litigation.

And how does one find out if they've won one of these coveted awards? In the US, it seems that one receives a phone call at home, very early in the morning. Still only half-awake, one picks up the phone, and wonders if the person on the other end is a crank caller with a bad Swedish accent. Then one receives several dozen other phone calls, usually from reporters who have also woken up at unreasonably early hours. And then one realizes, "Holy Crap, I'm a laureate! I'd better have some coffee!!"

As of this writing, only the prize for physiology or medicine has been awarded. The winners: a pair of researchers, Andrew Fire and Craig Mello, who discovered RNA interference (RNAi). This natural process effectively silences genes like the mute button on a stereo, and can be used both experimentally (to answer the question, "Hey, what happens when I turn this gene off?") and potentially therapeutically in diseases like cancer.

The unusual thing about this particular award is that it came so quickly. The researchers only published their seminal work on the subject 8 years ago. Nobel awardees (or laureates) typically don't receive awards until decades after the actual accomplishment for which they are nominated.

And now, for a shameless plug - the Nobels' lesser-known stepcousin, the IgNobel Prizes, will be awarded this Thursday night. Only slightly less prestigious (they can make or break careers, you know), the Igs honor those achievements which make people laugh, and then make people think. The awards, which are handed out by actual Nobel laureates (there are one or two of them just hanging around in Boston), are awarded in a ceremony with all appropriate pomp and circumstance. I can say that because I will be on stage helping herd the winners through the ceremony.

[For more on the prizes, check out the Nobel website or a recent story from Reuters. For more on the IgNobels, including how to get tickets or see the webcast, take a look at Improbable.com.]

El Nino? Ay caramba!

Last week, the National Oceanic and Atmospheric Administration (NOAA) announced that a new El Nino event is building. The announcement was based on an increase in sea surface temperatures in the Pacific Ocean off the coast of South America...hallmark of a rising El Nino.

El Nino is part of a weather pattern called the Southern Oscillation, a see-saw of temperatures and air pressure between the eastern and western Pacific that can change the normal movement of moisture and wind across the ocean. El Nino (Spanish for "Christ child," a reference to the fact that it always arises late in the year) has a little sister called La Nina, which is characterized by lower-than-normal temperatures near South America.

Why is this a big deal? Because El Ninos can disrupt weather globally. El Ninos can make things wetter in North America, drier in South America and Australia, and can put a damper on hurricane formation in the Caribbean - like what might be happening this year.

The length of time El Ninos last can vary. This one is predicted to hold on until early next year. But then again, no one thought an El Nino was going to occur this year until the last few weeks.

[Check the NOAA website for more information on this El Nino event. To learn more about El Ninos in general, check out NOVA.]

Summer vacation is over...

...and the Scriptorium is back. My apologies for the silence the last few months.

It's a planet! Wait, no it's not, but it is. Hold on, there are 12?

Remember the mnemonic you learned as a kid so you could remember the names of the nine planets? It was probably one of these:

"My Very Eager Mother Just Served Us Nine Pickles."

"Mother Very Easily Made Jane Stop Using Nail Polish."

"My Very Enormous Monster Just Sucked Up Nine Planets."

Well, it's time to unlearn them, because the nine-planet solar system everyone thought was set in stone after the discovery of Pluto in the 1930s just got tossed. Welcome to the age of the 12-planet solar system, thanks to the new definition of "planet" proposed at a meeting of the International Astronomical Union. They also propose to create a new class of mini-planet called a "pluton."

With the new definition comes the following changes:

1. Pluto gets downgraded from planet to pluton
2. Charon, Pluto's moon (more on that in a second), gets bumped up to pluton designation
3. Ceres, a really big asteroid in the belt between Mars and Jupiter, bypasses pluton-ness and goes straight to planet
4. The large body discovered in 2003 beyond Pluto, which has the melodic name 2003UB313 (unofficially dubbed Xena by its discoverer), becomes the third member of the plutons.

Pluto and Charon are seeing the biggest change in the org chart of Solar System, Inc. Charon gets promoted to independent status - a moon no more - because it is so heavy that the center of gravity between it and Pluto is smack in between them (meaning they revolve around a point in space). Contrast this with the Earth and our moon, where the center of gravity of the two-body system is in the Earth itself (so that the moon actually revolves around us). Thus, Pluto and Charon become the solar system's first double planet.

There may be more plutons on the way; if the definition is approved, then a host of other bodies in the solar system, including other asteroids and maybe even other moons, will earn the title. Meaning we could potentially end up with a solar system with hundreds of such mini-planets. And some really long mnemonics to remember them.

Oh, and the main criterion for joining the planetary club? Roundness.

[Read on at New Scientist to learn about the debate over the definition of planet. And many thanks to my father-in-law for the mnemonics.]

UPDATE: Turns out that if the IAU accepts the new planetary definition, things could get really weird in the solar system, with our moon even eventually qualifying for planethood. Tune back in in about, oh, 5 billion years.

ANOTHER UPDATE: Scratch pluton, make that "dwarf planet." And it's 8, not 12.

Do these bacteria make my thighs look fat?

Believe it or not, you have a bacterial infection in your intestines right now. And it's OK. We all have bacteria in our guts, ones that live with our bodies in a mutually beneficial (or "symbiotic") relationship. We provide a nice, safe, warm environment, and in return they help us digest our food. There are certain foods that we just couldn't digest without our helpful little microbes, and certain proteins, amino acids, and other nutrients we need that we would have a hard time absorbing if they weren't preprocessed.

Now it appears that they may also influence how well we absorb sugars and store them...and when we store sugars, we store them as fat. Researchers at Washington University inoculated germ-free mice with different microorganisms or a combination of microorganisms and measured how they digested their food. The mice given the combination of bugs digested the sugars within their feed more efficiently, but instead of burning them off, the mice stored them as fat, causing them to gain more weight.

The researchers look at the study as a "logical extension of the human genome project - one designed to define the microbial side of ourselves." They even managed to drop the word "microbiome." (Add that one to the list.)

The take home message? While dieting and exercise are still the best ways to lose and control weight, the bugs in your gut may have something to say about it. The researchers hypothesize that one day treatments that alter the microbial composition of our intestines could be a vital aspect of nutritional control.

[Many thanks to EurekAlert and LiveScience.]

Genetically carnivorous?

Twin studies are often used to probe the relative contributions of nature and nurture - that is, heredity and environment - to behavioral and other traits. The results can be eerie at times; the popular and scientific literature are rife with descriptions of twins who are separated at birth and meet decades later to find that they have followed the exact same career paths, have the same likes and dislikes, and have similar personality traits.

How about food preferences? Researchers in England surveyed the parents of hundreds of sets of identical and fraternal to determine the heritability of food preference. The results? Kids are more likely to inherit a taste for fish or meat, while preferences for vegetables - and dessert(!?) - are more heavily influenced by availability and/or parental choice.

Does this mean we can breed out vegans?

Believe it or not, this research does have a good purpose. The leader of the research group, Professor Jane Wardle of the Health Behavior Unit at University College London, is keenly interested in what shapes children's food preferences so as to better understand why kids diets are so, well, bad. If you can mold their diet when they're young, maybe you can keep them from getting cancer and heart disease later.

[Check out Yahoo for more, but if you really want to get to the meat of the story, check out Prof. Wardle's UCL faculty page.]