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Saturday, January 7
A cop dies & kin
by
salvador rosillo
on Sat 07 Jan 2006 10:19 PM EST
DNA Offers New Insight Concerning Cat Evolution
by
salvador rosillo
on Sat 07 Jan 2006 10:17 PM EST
Rui Vieira/Associated Press
Researchers have gained a major insight into the evolution of cats by showing how they migrated to new continents and developed new species as sea levels rose and fell. Researchers have gained a major insight into the evolution of cats by showing how they migrated to new continents and developed new species as sea levels rose and fell. About nine million years ago - two million years after the cat family first appeared in Asia - these successful predators invaded North America by crossing the Beringian land bridge connecting Siberia and Alaska, a team of geneticists writes in the journal Science today. Later, several American cat lineages returned to Asia. With each migration, evolutionary forces morphed the pantherlike patriarch of all cats into a rainbow of species, from ocelots and lynxes to leopards, lions and the lineage that led to the most successful cat of all, even though it has mostly forsaken its predatory heritage: the cat that has induced people to pay for its board and lodging in return for frugal displays of affection. This new history of the family, known as Felidae, is based on DNA analyses of the 37 living species performed by Warren E. Johnson and Stephen J. O'Brien of the National Cancer Institute and colleagues elsewhere. Before DNA, taxonomists had considerable difficulty in classifying the cat family. The fossil record was sparse and many of the skulls lacked distinctiveness. One scheme divided the family into Big Cats and Little Cats. Then, in 1997, Dr. Johnson and Dr. O'Brien said they thought most living cats fell into one of eight lineages, based on the genetic element known as mitochondrial DNA. Having made further DNA analyses, the researchers have drawn a full family tree that assigns every cat species to one of the lineages. They have also integrated their tree, which is based solely on changes in DNA, with the fossil record. The fossils, which are securely dated, allow dates to be assigned to each fork in the genetic family tree. Knowing when each species came into existence, the Johnson-O'Brien team has been able to reconstruct a series of at least 10 intercontinental migrations by which cats colonized the world. The cheetah, for instance, now found in Africa, belongs to a lineage that originated in North America and some three million years ago migrated back across the Bering land bridge to Asia and then Africa. Dr. O'Brien said the cats were very successful predators, second only to humans, and quickly explored new territories as opportunity arose. Sea levels were low from 11 million to 6 million years ago, enabling the first modern cats, in paleontologists' perspective (saber-tooth tigers are ancient cats), to spread from Asia west into Africa, creating the caracal lineage, and east into North America, generating the ocelot, lynx and puma lineages. The leopard lineage appeared around 6.5 million years ago in Asia. The youngest of the eight lineages, which led eventually to the domestic cat, emerged some 6.2 million years ago in Asia and Africa, either from ancestors that had never left Asia or more probably from North American cats that had trekked back across the Bering land bridge. Sea levels then rose, confining each cat species to its own continent, but sank again some three million years ago, allowing a second round of cat migrations. It was at this time that the ancestors of the cheetah and the Eurasian lynxes colonized the Old World from the New. Chris Wozencraft, an authority on the classification of carnivorous mammals, said the new cat family tree generally agreed with one that he had just published in Mammal Species of the World, a standard reference. Dr. Wozencraft, a taxonomist at Bethel College in Indiana, based his classification on fossil and zoological information, as well as on DNA data already published by Dr. O'Brien's laboratory. Cat fossils are very hard to tell apart, because they differ mostly just in size, and the DNA data emerging over the last decade has helped bring the field from confusion to consensus, Dr. Wozencraft said. Despite their evolutionary success, most of the large cats are in peril because their broad hunting ranges have brought them into collision with people. "With the exception of the house cat and a few other small cat species, nearly every one of the 37 species is considered endangered or threatened," Dr. Johnson and Dr. O'Brien write in the current Annual Review of Genomics and Human Genetics. Fewer than 15,000 tigers, cheetahs and snow leopards remain in the wild, they estimate, and pumas and jaguar populations have been reduced to about 50,000 each.
Nearly 100, LSD's Father Ponders His 'Problem Child'
by
salvador rosillo
on Sat 07 Jan 2006 10:11 AM EST
Marc Latzel/Lookat
"LSD spoke to me. He came to me and said, 'You must find me.' He told me, 'Don’t give me to the pharmacologist.'" ALBERT Hofmann, the father of LSD, walked slowly across the small corner office of his modernist home on a grassy Alpine hilltop here, hoping to show a visitor the vista that sweeps before him on clear days. But outside there was only a white blanket of fog hanging just beyond the crest of the hill. He picked up a photograph of the view on his desk instead, left there perhaps to convince visitors of what really lies beyond the windowpane. Mr. Hofmann will turn 100 on Wednesday, a milestone to be marked by a symposium in nearby Basel on the chemical compound that he discovered and that famously unlocked the Blakean doors of perception, altering consciousnesses around the world. As the years accumulate behind him, Mr. Hofmann's conversation turns ever more insistently around one theme: man's oneness with nature and the dangers of an increasing inattention to that fact. "It's very, very dangerous to lose contact with living nature," he said, listing to the right in a green armchair that looked out over frost-dusted fields and snow-laced trees. A glass pitcher held a bouquet of roses on the coffee table before him. "In the big cities, there are people who have never seen living nature, all things are products of humans," he said. "The bigger the town, the less they see and understand nature." And, yes, he said, LSD, which he calls his "problem child," could help reconnect people to the universe. Rounding a century, Mr. Hofmann is physically reduced but mentally clear. He is prone to digressions, ambling with pleasure through memories of his boyhood, but his bright eyes flash with the recollection of a mystical experience he had on a forest path more than 90 years ago in the hills above Baden, Switzerland. The experience left him longing for a similar glimpse of what he calls "a miraculous, powerful, unfathomable reality." "I was completely astonished by the beauty of nature," he said, laying a slightly gnarled finger alongside his nose, his longish white hair swept back from his temples and the crown of his head. He said any natural scientist who was not a mystic was not a real natural scientist. "Outside is pure energy and colorless substance," he said. "All of the rest happens through the mechanism of our senses. Our eyes see just a small fraction of the light in the world. It is a trick to make a colored world, which does not exist outside of human beings." He became particularly fascinated by the mechanisms through which plants turn sunlight into the building blocks for our own bodies. "Everything comes from the sun via the plant kingdom," he said. MR. HOFMANN studied chemistry and took a job with the Swiss pharmaceutical company Sandoz Laboratories, because it had started a program to identify and synthesize the active compounds of medically important plants. He soon began work on the poisonous ergot fungus that grows in grains of rye. Midwives had used it for centuries to precipitate childbirths, but chemists had never succeeded in isolating the chemical that produced the pharmacological effect. Finally, chemists in the United States identified the active component as lysergic acid, and Mr. Hofmann began combining other molecules with the unstable chemical in search of pharmacologically useful compounds. His work on ergot produced several important drugs, including a compound still in use to prevent hemorrhaging after childbirth. But it was the 25th compound that he synthesized, lysergic acid diethylamide, that was to have the greatest impact. When he first created it in 1938, the drug yielded no significant pharmacological results. But when his work on ergot was completed, he decided to go back to LSD-25, hoping that improved tests could detect the stimulating effect on the body's circulatory system that he had expected from it. It was as he was synthesizing the drug on a Friday afternoon in April 1943 that he first experienced the altered state of consciousness for which it became famous. "Immediately, I recognized it as the same experience I had had as a child," he said. "I didn't know what caused it, but I knew that it was important."
Coming Soon to TV Land: The Internet, Actually
by
salvador rosillo
on Sat 07 Jan 2006 10:02 AM EST
LAS VEGAS, Jan. 6 - What would a world with television coming through the Internet be like? Instead of tuning into programs preset and determined by the broadcast network or cable or satellite TV provider, viewers would be able to search the Internet and choose from hundreds of thousands of programs sent to them from high-speed connections. At the International Consumer Electronics Show here this week, a future dominated by Internet Protocol TV, or IPTV, seemed possible, maybe even inevitable. Giants like Yahoo and Google turned their attentions to offering new Internet programming. Hardware companies like Intel introduced chips and platforms that can push videos sent via an Internet connection to living room screens. And Microsoft looked for alliances that would allow its software to dominate living rooms as well as the home office. "At one level it's clear that the dam has broken," said Paul Otellini, chief executive of Intel. "There's an inevitable move to use the Internet as a distribution medium, and that's not going to stop." The rapid emergence of the consumer electronics and computer companies as Internet video providers is certain to challenge the control of the cable, telephone and satellite companies, which seek to dominate the distribution of digital content to the home. Competition has intensified as more consumers have upgraded to digital televisions. Indeed, the easy availability of on-demand content over the Internet is certain to accelerate consumer expectations that they will have more control over digital video content, both to watch programs when they want as well as to move video programs to different types of displays in different rooms of the home. "Appointment-based television is dead," said William Randolph Hearst III, a partner at Kleiner Perkins Caufield & Byers, the Silicon Valley venture capital firm. "The cable industry is really in danger of becoming commoditized." Mr. Hearst sits on the board of Akimbo, a provider of an Internet service that permits users to download video content via the Internet to a set-top box digital video player. This week, Akimbo announced its first mainstream content deal to enable its customers to download Hollywood movies for later viewing on their televisions. In the battle for the living room, cable, satellite, and increasingly, phone companies are trying to defend their turf by offering more choice through an array of content in video-on-demand programs. But fending off the Internet's openness will be a struggle, one that the online companies themselves lost years ago. At the onset of the dot-com era, large online service companies like AOL, Compuserve and MSN tried to lock customers into electronic walled gardens of digital information. But it quickly became apparent that no single company could compete with the vast variety of information and entertainment sources provided on the Web. The same phenomenon may well overtake traditional TV providers. Potentially, IPTV could replace the 100- or 500-channel world of the cable and satellite companies with millions of hybrid combinations that increasingly blend video, text from the Web, and even video-game-style interactivity. Though still new, IPTV is already commercially available in limited areas both in the United States and internationally. To date, the new digital Internet content is hard to find and of uneven quality. Moreover, the consumer electronics industry is still struggling to complete copy protection agreements with Hollywood and other content providers. But the advantage of IPTV is that it can potentially be deployed at lower cost than current cable television systems and can offer consumers features like the ability to record several programs simultaneously without having to add costly additional tuners. (And IPTV can potentially record many streams if bandwidth is available.) A prototype of one feature of the Microsoft IPTV service, known in the industry as a matrix channel, allows several baseball games to be viewed simultaneously along with textual information like player statistics. Internet search is also likely to play a defining role in shaping IPTV, according to executives attending the consumer electronics show. Both Yahoo and Google announced plans to distribute video at the show, and Yahoo showed a new application intended to be used with a high-definition television to ease the search for video content, stream digital video and permit users to keep their personal information and files in sync whether they are viewing a PC, TV or mobile phone.
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