Science Tuesday - Johnstown Flood, Dinosaurs, Dopamine, Human Sacrifice, and Cancer

Observatory: Research at the Source of a Pennsylvania Flood
By HENRY FOUNTAIN, The New York Times, October 27, 2009

Like many people who come to Johnstown, Pa., Carrie Davis Todd, a hydrologist who was hired to teach at a local university a little over a year ago, was curious about the great Johnstown Flood of 1889, in which 2,209 people were killed when a dam failed 14 miles away. “One of the first things I did was go out and look at the dam site,” Dr. Davis Todd said.

The lake behind the dam held a huge volume of water that roared down the winding course of the Little Conemaugh River before slamming into Johnstown in one of the worst disasters in American history. While there were many witness accounts of the dam failure and the torrent of water that ensued, Dr. Davis Todd, an assistant professor of geology at the University of Pittsburgh at Johnstown, was surprised to find that the beginnings of the flood had never been rigorously assessed.

( Read More )

Observatory: Two-Pound Dinosaur Holds North American Record
By HENRY FOUNTAIN, The New York Times, October 27, 2009

Small dinosaurs are big these days. Researchers recently announced the discovery of a tiny prototype of a Tyrannosaurus from China. Now paleontologists are reporting the smallest dinosaur ever found in North America.

The animal, Fruitadens haagarorum, had a body length of about 30 inches and weighed an estimated 2 pounds.

( Read More )

CT scan, left, of a female skull at a burial site at Ur. Women were buried with elaborate adornments, right, and warriors with their weapons.

At Ur, Ritual Deaths That Were Anything but Serene
By JOHN NOBLE WILFORD, The New York Times, October 27, 2009

A new examination of skulls from the royal cemetery at Ur, discovered in Iraq almost a century ago, appears to support a more grisly interpretation than before of human sacrifices associated with elite burials in ancient Mesopotamia, archaeologists say.

Palace attendants, as part of royal mortuary ritual, were not dosed with poison to meet a rather serene death. Instead, a sharp instrument, a pike perhaps, was driven into their heads.

( Read More )

Basics: A Molecule of Motivation, Dopamine Excels at Its Task
By NATALIE ANGIER, The New York Times, October 27, 2009

If you’ve ever had a problem with rodents and woken up to find that mice had chewed their way through the Cheerios, the Famous Amos, three packages of Ramen noodles, and even that carton of baker’s yeast you had bought in a fit of “Ladies of the Canyon” wistfulness, you will appreciate just how freakish is the strain of laboratory mouse that lacks all motivation to eat.

The mouse is physically capable of eating. It still likes the taste of food. Put a kibble in its mouth, and it will chew and swallow, all the while wriggling its nose in apparent rodent satisfaction.

Yet left on its own, the mouse will not rouse itself for dinner. The mere thought of walking across the cage and lifting food pellets from the bowl fills it with overwhelming apathy. What is the point, really, of all this ingesting and excreting? Why bother? Days pass, the mouse doesn’t eat, it hardly moves, and within a couple of weeks, it has starved itself to death.

Behind the rodent’s fatal case of ennui is a severe deficit of dopamine, one of the essential signaling molecules in the brain. Dopamine has lately become quite fashionable, today’s “it” neurotransmitter, just as serotonin was “it” in the Prozac-laced ’90s.

( Read More )

Cancers Can Vanish Without Treatment, but How?
By GINA KOLATA, The New York Times, October 27, 2009

Call it the arrow of cancer. Like the arrow of time, it was supposed to point in one direction. Cancers grew and worsened.

But as a paper in The Journal of the American Medical Association noted last week, data from more than two decades of screening for breast and prostate cancer call that view into question. Besides finding tumors that would be lethal if left untreated, screening appears to be finding many small tumors that would not be a problem if they were left alone, undiscovered by screening. They were destined to stop growing on their own or shrink, or even, at least in the case of some breast cancers, disappear.

( Read More )