Texas canyon carved in just three days

Normally, geologic events happen over hundreds of thousands of years. In January, I was surprised to read that the Mediterranean sea may have filled with ocean water in a mere two years. (Check out that post at the Lay Scientist.)

Again--I am surprised to find that in a mere three days, floodwaters carved this impressive 2.2-kilometer-long and 7-meter-deep canyon in solid Texas bedrock. In 2002, a particularly menacing rainstorm sent water gushing over Canyon Dam in central Texas, carving this sizable trench which has since dried up significantly.

Now that the canyon and associated rocks and formations are visible, Caltech geologist Michael Lamb and Texas State geologist Mark Fonstad took a look at the area upstream of the flood, examining rock weathering patterns to measure strength of water movement, using aerial photographs and topological measurements to deduce displacement of rocks during the big 2002 gush. Because the flood was able to pop out massive rocks and carry them far upstream, the geologists deduced the rate of canyon erosion to be extremely rapid.

This study provides a promising scientific look into the mechanics of so-called megafloods since, unlike the filling of the Mediterranean sea, the erosion of the Canyon Dam canyon was witnessed in-vivo. Says geologist Mark Lamb:

"This is one of a few places where models for canyon formation can be tested because we know the flood conditions under which this canyon formed. We're trying to build models of erosion rates so we can go to places like Mars and make quantitative reconstructions of how much water was there, how long it lasted, and how quickly it moved."

Lamb, M., & Fonstad, M. (2010). Rapid formation of a modern bedrock canyon by a single flood event Nature Geoscience DOI: 10.1038/ngeo894

      Photo credit: Michael Lamb, Caltech

PIC: REEEAALLY OLD SHOE

[The oldest shoe ever found--laces intact, stuffed with straw, and 5,500 years old. Don't walk in this. -UCLA]

Read about it:

This Shoe Had Prada Beat by 5,500 Years--New York Times

Ancient shoe unearths footprints from the past--UCLA news

Bones reveal first shoe-wearer--BBC

Artist Louise Bourgeois and Nature Imagery

Few artists can create sculpture that at once showcases nature imagery, betrays humanness and sensuality, and has a heavy artistic/conceptual weight. Louise Bourgeois was one of them. (Georgia O'Keeffe and Maya Lin also come to mind.) She died last week in New York City.

Some critics think (and I believe the artist herself once said) that her work was wholly personal--most of her sculptures were intended to convey a sense of protection against a harsh world outside one's self.

I've always seen a nurturing, playful side to her work, however undeniably introverted. And, what i construe as nature imagery--the giant spider, soft white grassish sculpture, sci fi coral reef-looking stuff--is more calming and wonder-inducing than anything else. It could be that the 'self' in these cases, that the artist wants to protect is the concept of ourselves undeniably embedded in the natural world.

I don't know about you, but the interconnectedness concept (ie how the scientific concept of energy flow ties all living and non-living matter together) always gives me a sense of invulnerability, or at least a lack of paranoia.

PIC: LIZARD JAW

[~10,000 year old lizard jaw, Rancho La Brea, Los Angeles. Photo Andie Thomer]

OCD and immune system linked

I have a friend who compulsively cleans his apartment.

He's a writer, too, so it stands to reason he either takes procrastinating to a whole new level, or there's something funky going on in his brain when he scrubs the kitchen grout with a toothbrush for hours.

Obsessive-compulsive disorder is a psychological disease, or that's how the scientific community portrays it. But, a new scientific study published in Cell this week takes on the disorder from a different perspective. Something funky IS going on there..

Mainly, the research team seems to have found: if you remove microglia--branchy cells whose main function is to roam around and keep the brain clean of infection--from the brain of an adult mouse, you get obsessive grooming behavior. The mouse brain goes haywire, seemingly afraid of infection itself, and the mice over-lick and over-pick themselves until some are virtually hair-free.

It's easy to look at psychological disorders like OCD, PTSD, generalized anxiety disorder, and many others and ask--what aberrant physical processes are a result of these conditions? Heart palpitations? Peptic ulcers? Panic episodes? But, it's relatively novel to even suggest that the underlying psychology is directly attributable to the presence or absence of a single cell.

Researcher Mario Capecchi says: "We're showing there is a direct relationship between a psychiatric disorder and the immune system, specifically cells named microglia that are derived from bone marrow" and are found in the brain, says Mario Capecchi, a distinguished professor of human genetics at the University of Utah School of Medicine. "There's been an inference. But nobody has previously made a direct connection between the two."

So maybe you're thinking--what if the process of ripping out important branchy cells in the brain is itself what irrevocably damages some circuit somewhere and renders mice OCD for life?

Not true. The researchers report--when the microglia cells were added back into the mouse brain (im sure this sounds easier than it is), the mice lose their OCD affectation. The authors don't claim to know the biochemical process by which these immune-functioning brain cells might cause this kind of OCD in mice (or for that matter whether humans operate the same way), but it's safe to say that it's worth further investigation.

BTW--geneticist Mario Capecchi co-won a Nobel Prize in Physiology or Medicine in 2007

Chen, S., Tvrdik, P., Peden, E., Cho, S., Wu, S., Spangrude, G., & Capecchi, M. (2010). Hematopoietic Origin of Pathological Grooming in Hoxb8 Mutant Mice Cell, 141 (5), 775-785 DOI: 10.1016/j.cell.2010.03.055