Day: March 21, 2010

Our early tree-dwelling ancestors were also bipedal

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Experiments by a UA anthropologist and his colleagues show that fossil footprints made 3.6 million years ago are the earliest direct evidence of early hominins using the kind of efficient, upright posture and gait now seen in modern humans.
More than three million years ago, the ancestors of modern humans were still spending a considerable amount of their lives in trees, but something new was happening.

David Raichlen…and his colleagues…have developed new experimental evidence indicating that these early hominins were walking with a human-like striding gait as long as 3.6 million years ago.

A trackway of fossil footprints preserved in volcanic ash deposited 3.6 million years ago was uncovered in Laetoli, Tanzania, more than 30 years ago. The significance of those prints for human evolution has been debated ever since.

The most likely individuals to have produced these footprints, which show clear evidence of bipedalism, or walking on two legs, would have been members of the only bipedal species alive in the area at that time, Australopithecus afarensis. That species includes “Lucy,” whose skeletal remains are the most complete of any individual A. afarensis found to date…

Since the Laetoli tracks were discovered, scientists have debated whether they indicate a modern human-like mode of striding bipedalism, or a less-efficient type of crouched bipedalism more characteristic of chimpanzees whose knees and hips are bent when walking on two legs.

To resolve this, Raichlen and his colleagues devised the first biomechanical experiment explicitly designed to address this question…

“Based on previous analyses of the skeletons of Australopithecus afarensis, we expected that the Laetoli footprints would resemble those of someone walking with a bent knee, bent hip gait typical of chimpanzees, and not the striding gait normally used by modern humans,” Raichlen said. “But to our surprise, the Laetoli footprints fall completely within the range of normal human footprints…”

“What is fascinating about this study is that it suggests that, at a time when our ancestors had an anatomy well-suited to spending a significant amount of time in the trees, they had already developed a highly efficient, modern human-like mode of bipedalism,” said Gordon.

True Believers may ignore this entire post and the linked article. Of course.

You may now return to jiggling your beads or whatever it is that you fondle on a Sunday evening after all televised sports have ended.

The Plastiki sets sail

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The Plastiki, a boat with a hull built of 12,500 plastic bottles, set sail from a Sausalito yacht harbor this morning on a risky and adventurous voyage across the Pacific.

The purpose, said expedition leader David de Rothschild, is to draw attention to the health of the oceans and to demonstrate the value of recycled plastic bottles. De Rothschild and his crew of five hope to sail to Australia, a voyage of about 11,000 nautical miles.

The Plastiki, named in honor of Norwegian explorer Thor Hyderdahl’s raft Kon Tiki, is a boat like no other in the world. Besides the hull of recycled plastic water and soda bottles, the vessel is made of a hardened plastic called PET.

The boat is a twin-hulled catamaran rigged as a ketch. It will rely on the wind for propulsion and has only a small auxiliary engine. No such boat has ever made an ocean passage before.

Skipper Jo Royle said the first port of call will be one of the Line Islands, a small group of atolls south of Hawaii.

The voyage can be followed on the Internet at www.theplastiki.com.

Bon voyage, folks. It ain’t ever easy with a craft this small.

Light can twist rigid mechanical structures

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In findings that took the experimenters three years to believe, University of Michigan engineers and their collaborators have demonstrated that light itself can twist ribbons of nanoparticles.

Matter readily bends and twists light. That’s the mechanism behind optical lenses and polarizing 3-D movie glasses. But the opposite interaction has rarely been observed, said Nicholas Kotov, principal investigator on the project…

While light has been known to affect matter on the molecular scale—bending or twisting molecules a few nanometers in size—it has not been observed causing such drastic mechanical twisting to larger particles. The nanoparticle ribbons in this study were between one and four micrometers long. A micrometer is one-millionth of a meter.

“I didn’t believe it at the beginning,” Kotov said. “To be honest, it took us three and a half years to really figure out how photons of light can lead to such a remarkable change in rigid structures a thousand times bigger than molecules.”

Kotov and his colleagues had set out in this study to create “superchiral” particles—spirals of nano-scale mixed metals that could theoretically focus visible light to specks smaller than its wavelength. Materials with this unique “negative refractive index” could be capable of producing Klingon-like invisibility cloaks, said Sharon Glotzer, a professor…also involved in the experiments. The twisted nanoparticle ribbons are likely to lead to the superchiral materials, the professors say…

The light twists the ribbons by causing a stronger repulsion between nanoparticles in them.

The twisted ribbon is a new shape in nanotechnology, Kotov said. Besides superchiral materials, he envisions clever applications for the shape and the technique used to create it…

This newly-discovered twisting effect could also lead to microelectromechanical systems that are controlled by light. And it could be utilized in lithography, or microchip production.

I’d love to see this in stop-motion. Might also help me to understand. Descriptive geometry is one of my least-favorite subjects.

Environmental and social impact of the ‘Livestock Revolution’

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Global meat production has tripled in the past three decades and could double its present level by 2050, according to a new report on the livestock industry by an international team of scientists and policy experts. The impact of this “livestock revolution” is likely to have significant consequences for human health, the environment and the global economy…

“This is the first time that we’ve looked at the social, economic, health and environmental impacts of livestock in an integrated way and presented solutions for reducing the detrimental effects of the industry and enhancing its positive attributes,” Harold A. Mooney said.

Among the key findings in the report are:

More than 1.7 billion animals are used in livestock production worldwide and occupy more than one-fourth of the Earth’s land.

Production of animal feed consumes about one-third of total arable land.

Livestock production accounts for approximately 40 percent of the global agricultural gross domestic product.

The livestock sector, including feed production and transport, is responsible for about 18 percent of all greenhouse gas emissions worldwide.

Eating less meat helps. Eating less animal fat helps you live longer.

RTFA – for lots of analysis and stats – and especially links to related sites. Lots of info.

I enjoy consuming new information as much as barbecued pork. 🙂

Teabaggers turn to racist, homophobe chants at D.C. rally

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The tea party movement is disturbingly racist and reactionary, from its roots to its highest branches. On Saturday, as a small group of protesters jammed the Capitol and the streets around it, the movement’s origins in white resistance to the Civil Rights Movement was impossible to ignore. Here’s only what the mainstream media is reporting, ignoring what I’m seeing on Twitter and left wing blogs:

Civil rights hero Rep. John Lewis was taunted by tea partiers who chanted “nigger” at least 15 times, according to the Associated Press (we are not cleaning up language and using “the N-word” here because it’s really important to understand what was said.) First reported on The Hill blog (no hotbed of left-wing fervor), the stories of Lewis being called “nigger” were confirmed by Lewis spokeswoman Brenda Jones and Democratic Rep. Andre Carson, who was walking with Lewis. “It was like going into the time machine with John Lewis,” said Carson, a former police officer. “He said it reminded him of another time.”

Another Congressional Black Caucus leader, Rep. Emanuel Cleaver, was spat upon by protesters. The culprit was arrested, but Cleaver declined to press charges.

House Majority Whip James Clybourn told reporters: “I heard people saying things today that I have not heard since March 15, 1960, when I was marching to try to get off the back of the bus.”

There were many reports that Rep. Barney Frank was called a “faggot” by protesters, but the one I saw personally was by CNN’s Dana Bash, who seemed rattled by the tea party fury. Frank told AP: “It’s a mob mentality that doesn’t work politically…”

So I’m having a hard time tonight trying to believe almost uniformly white tea partiers are anything other than a racist, right-wing reaction to the election of an African American president who brings with him feminists and gays (even if he doesn’t do as much for them as they would ideally like). I’m having a hard time seeing the tea partiers as anything other than the spawn of George Wallace racism – the movement Pat Buchanan bragged to me that Richard Nixon made his own…

Anyone surprised?

Pharmco missed deadline – loses patent extension!

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The United States Patent and Trademark Office on Friday again denied the Medicine Company’s request to extend the life of the patent protecting its main drug, the blood thinner Angiomax.

Medicines has been trying since 2001 to undo an error, when it narrowly missed a 60-day deadline for requesting the patent extension. Because the patent office would not accept the late application, the patent has been scheduled to expire next Tuesday, rather than in late 2014.

On Tuesday, however, a federal judge ordered the patent office to reconsider its rejection of the extension, suggesting the agency had been too strict in interpreting the law regarding the 60-day deadline. The judge, Claude M. Hilton of the United States District Court in Alexandria, Va., also told the patent office to keep the patent in force while it conducted its reconsideration.

By Friday, however, the patent office had already concluded its review, telling the company that it would stick with its previous decisions and would not accept the company’s application.

The decision, and especially how rapidly it was made, stunned and infuriated the company…

The Patent Office is, after all, usually ready to rollover for corporate America.

In a 15-page decision, accompanied by more than 300 pages of attachments, the Patent Office defended its decision. It said Medicines had waited until the last minute to file the fairly simple patent extension application. It also said the company did not sue the patent office until the patent had nearly expired, instead spending years lobbying Congress. “MDCO’s dire situation is therefore exclusively of its own making,” it said.

Smile, you’re on Candid Camera – at Best Buy, Wal-Mart

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The scenes being examined in this office may seem like random shopping bloopers, but they are meaningful to stores that are striving to engineer a better experience for the consumer, and ultimately, higher sales for themselves. Such clips, retailers say, can help them find solutions to problems in their stores — by installing seating and activity areas to mollify children, for instance, or by lowering shelves so merchandise is within easy reach.

Privacy advocates, though, are troubled by the array of video cameras, motion detectors and other sensors monitoring the nation’s shopping aisles…

Companies that employ this technology say it is used strictly to determine characteristics like age and gender, which help them discover how different people respond to various products. But privacy advocates fear that as the technology becomes more sophisticated, it will eventually cross the line and be used to identify individual consumers and gather more detailed information on them…

Some degree of privacy, experts say, is necessary as a matter of decency.

“When someone’s watching me, I’m going to act differently than when I think I’m alone,” consumer advocate, Katherine Albrecht said. “Did I pick my nose? What was I doing? What did they see..?”

The companies that install and analyze video for retailers say that they are sensitive to privacy issues but that the concerns are overblown. They say they are not using the technology to identify consumers but to give them easier and more enjoyable shopping experiences. And, they added, they have the sales results to prove it…

But industry professionals said interest in analyzing shoppers was growing. Video analysis companies said nearly every major chain was or had been a client, including giants like Wal-Mart Stores and Best Buy.

So, remove the words “shoppers” and insert “voters”, “office-workers”, “students” – does the question become more or less meaningful?

RTFA. A few examples which illustrate why you should be interested.