Tuesday, July 29, 2008

native

A single population of prehistoric Siberians crossed the Bering Strait into Alaska and subsequently fanned out to populate North and South America, according to a new genetic analysis of present-day indigenous Americans. http://louisejesheehan.blogspot.com

The study also hints that early Americans reached Central and South America by migrating down the Pacific coast by land or sea and only later spread into the interior of South America.

"We have good evidence that a single migration [from Siberia] contributed a large fraction of the ancestry of the Americas," says population geneticist Noah Rosenberg of the University of Michigan in Ann Arbor, who led the large international study team. http://louisejesheehan.blogspot.com

The finding draws on the largest database of Native American genetics ever compiled. The data include DNA from nearly 500 people belonging to 29 groups scattered across Canada, Mexico, Central America, and South America. The researchers also studied samples from 14 Tundra Nentsi individuals living in eastern Siberia.

"They should be commended for bringing together an enormous database, something no one has done before," says Tom Dillehay, an archaeologist at Vanderbilt University in Nashville.

The team examined 678 genetic markers in the human genome and found that one of the markers ties every Native American group to the Tundra Nentsi. The marker, moreover, is found nowhere else in the world. "It's extremely difficult to explain this kind of pattern unless all of the Native American populations ... have a large degree of shared ancestry," says Rosenberg.

In addition, the Canadian groups share more genes with the Siberians than do the groups in Central and South America, Rosenberg and his team report online in the November PLoS Genetics.

Tracing further migration through the Americas, the team then correlated genetic variations among different tribes with each group's location as measured along inland or coastal routes. The genetic data suggest that most migration to Central and South America followed the coast.

"That's the easy way south," says Vance Holliday, an archaeologist at the University of Arizona in Tucson. He cautions, however, that the groups that populated the South American interior would have had to surmount the formidable Andes Mountains.

Despite the migration findings, Holliday and Dillehay both say that southward migration along interior routes should still be considered. Dillehay notes that the current study excludes Native Americans from the United States and eastern Brazil. "It's a sampling bias," he says, that might have erroneously favored the Pacific coast migration model.

Rosenberg says that a second paper will soon address the genetics of tribes in the United States and whether there was more than one major Siberian migration.

While the study points to an eastern Siberian origin for most of the genes that spread across the Americas, it can't rule out small genetic contributions from other groups, says Kari Britt Schroeder of the University of California, Davis. In 2001, scientists unearthed 8,000- to 11,000-year-old skulls in Brazil that strikingly resemble today's Australian aborigines (SN: 4/7/01, p. 212). The find fueled speculation that several waves of immigrants from different parts of Asia reached the Americas.

"Even if Native Americans share a lot of ancestry from a single origin, there still could be contributions from other groups," says Schroeder.

Tuesday, July 22, 2008

birchington

Hydroponic farming is coming to the U.K.—70 soccer fields worth of it.
http://louis-j-sheehan.biz

Outside of Birchington in far southeastern England, workers are finishing the first of what will be seven giant greenhouses for growing tomatoes, cucumbers and peppers. Thanet Earth, as the complex is cleverly called, will cover around 220 acres of Kent County by its 2010 completion, according to the Daily Mail. In the greenhouses, plants will hang from a 26-foot-high ceiling. A drip will supply them with water, and also the nutrients they need and would normally take from soil, like potassium, magnesium, phosphate, and nitrogen.
http://louis-j-sheehan.biz

Greenhouse operators will deploy bees to pollinate the plants, and wasps to keep pests like aphids from wrecking their rows and rows of produce.

It’s not hard to see the practical reasons why Britons would go hydroponic: Thanet Earth’s proponents say the £80 million (approximately $160 million) project will produce 2.5 million tomatoes every week. That’s not bad for a country used to importing much of its produce—the BBC says half of the U.K.’s fruit and 95 percent of its vegetables come from abroad.

But not everyone is so thrilled. While the sun supplies much of the energy for normal agriculture, growing hydroponic crops year-round could be an energy glutton. You have to shine artificial light on tomatoes to trick them into growing in February, and 220 acres is a lot of artificial light. Growing hydroponic plants should save water compared to soil farming, but there’s also a lot of good soil now buried beneath glass and concrete, and any archaeologists who many have wanted to excavate the historical area are out of luck.

British foodies aren’t terribly happy with this trend, either. Where’s the culinary romance in a factory-grown cucumber? In the Daily Mail story, Jeanette Longfield of the food campaign group Sustain brings up the French word “terroir,” which means the specific traits a food gets from its soil and environment and is often used to start arguments about wine. Hydroponic tomatoes all have the same terroir, she argues, or none at all.

Lastly, we wrote earlier this week about the origins of the current salmonella scare in American tomatoes, and Keith Warriner of the University of Guelph in Ontario told DISCOVER that it was actually easier for pathogens to establish themselves in the hydroponic greenhouse compared to the field. According to the United States Department of Agriculture, salmonella can enter a hydroponic facility on tools, water, or workers’ clothing. So it seems that tightly-controlled greenhouse might not be so easy to control after all.

Wednesday, July 9, 2008

morgan

May 16, Monday. I yesterday took a steamer with a small company, consisting among others of Postmaster-General Blair, Senators Doolittle and Grimes, Messrs. Rice and Griswold of the Naval Committee, Count Rosen of the Swedish Navy, Mr. Hale (the newly selected Consul-General to Egypt), G. W. Blunt and Assistant Secretary Fox, Commander Wise, Dr. Horwitz, and two or three others, and went down the Potomac to Belle Plain. The day was pleasant and the sail charming. We reached Belle Plain about two P.M. and left a little past five. Is a rough place with no dwelling, — an extemporized plank-way from the shore some twenty or thirty rods in the rear. Some forty or fifty steamers and barges, most of them crowded with persons, were there. Recruits going forward to reinforce Grant’s army, or the wounded and maimed returning from battle. http://members.greenpeace.org/blog/purposeforporpoise Rows of stretchers, on each of which was a maimed or wounded Union soldier, were wending towards the steamers which were to bear them to Washington, while from the newly arrived boats were emerging the fresh soldiers going forward to the field. Working our way along the new and rough-made road, through teams of mules and horses, we arrived at the base of a hill some two or three hundred feet in height, and went up a narrow broken footpath to the summit, on which were the headquarters of General Abercrombie and staff. The ascent was steep and laborious. We had expected to find the prisoners here, but were told they were beyond, about one and a half miles. The majority were disposed to proceed thither, and, though tired and reluctant, I acquiesced. The prisoners, said to be about 7000 in number, were encamped in a valley surrounded by steep hills, the circumference of the basin being some two or three miles. Returning, we passed through the centre of this valley or basin. The prisoners were rough, sturdy-looking men, good and effective soldiers, I should judge. Most of them were quiet and well-behaved, but some few of them were boisterous and inclined to be insolent. http://members.greenpeace.org/blog/purposeforporpoise

One of the prisoners, a young man of some twenty-five, joined me and inquired if I resided in the neighborhood. I told him at a little distance. He wished to exchange some money, Rebel for greenbacks. When I told him that his was worthless, he claimed it was better than greenbacks though not current here. I asked him if they had not enough of fighting, opposing the Union and lawful authority. He said no, there was much more fighting yet to be done. Claimed that Lee would be in Fredericksburg before the Union army could get to Richmond. Would not believe that J. E. B. Stuart was killed, news of which I received just as I came on board the boat this morning. He was earnest, though uninformed, and said he was from western North Carolina. Returning, we reached Washington at 9 P.M.

To-day I have been busy in preparing two or three letters and matters for Congress.

Governor Morgan called on me relative to abuses in cotton speculations, and malconduct of Treasury agents and others. Some of the malpractices which are demoralizing the army and the officials and disgusting the whole people in the lower Mississippi are becoming known, and will, I trust, lead to legislative correction. As Morgan introduced the subject and thought proper to consult me, I freely gave him facts and my views, which conflict with Chase and the Treasury management. A bill which Morgan showed me is crudely drawn but introduces, or makes, an entire change. It is not, in some of its features, what I should have proposed, but it will improve on the present system.