1. Our Oldest Ancestor, "Ardi"
With her long, elegant fingers, 4-ft. frame and a head no larger than a bonobo's, it's hard not to feel a certain fondness for little Ardi, the oldest skeleton of a prehuman hominid ever found. Painstakingly pieced together from more than 100 crushed fossil fragments unearthed in Ethiopia, this female specimen of Ardipithecus ramidus (Ardi, for short) lived 4.4 million years ago and had remained anonymous until 1992, when her fragments were first discovered. After 17 years of research, a team of scientists led by Tim D. White from the University of California, Berkeley, published a comprehensive analysis of Ardi in October, in a series of articles in the journal Science. Among the team's revelations: Ardi was surprisingly unchimplike despite being the earliest known descendant of the last common ancestor shared by humans and chimps. Also, she was capable of walking on two feet despite living in an area of woodland and forest — a finding that downplays the importance of open grasslands to the evolution of human bipedalism.
2. The Human Epigenome, Decoded
The decoding of the human genome nearly a decade ago fueled expectations that an understanding of all human hereditary influences was within sight. But the connections between genes and, say, disease turned out to be far more complicated than imagined. What has since emerged is a new frontier in the study of genetic signaling known as epigenetics, which holds that the behavior of genes can be modified by environmental influences and that those changes can be passed down through generations. So people who smoke cigarettes in their youth, for example, sustain certain epigenetic changes, which may then increase the risk that their children's children will reach puberty early. In October, a team led by Joseph Ecker at the Salk Institute in La Jolla, Calif., studied human skin and stem cells to produce the first detailed map of the human epigenome. By comparing this with the epigenomes of diseased cells, scientists will be able to work out how glitches in the epigenome may lead to cancers and other diseases. The study, which was published in the journal Nature, is a giant leap in geneticists' quest to better understand the strange witches' brew of nature and nurture that makes us who we are.
3. Gene Therapy Cures Color Blindness
Modern science already offers ways to enhance your mood, sex drive, athletic performance, concentration levels and overall health, but a discovery in September suggests that truly revolutionary human enhancement may soon move from science fiction to reality. A study in Nature reported that a team of ophthalmologists had injected genes that produce color-detecting proteins into the eyes of two color-blind monkeys, allowing the animals to see red and green for the first time. The results were shocking to most — "We said it was possible, but every single person I talked to said, 'Absolutely not,' " said study co-author Jay Neitz of the University of Washington — and raised the possibility that a range of vision defects could someday be cured. That's a transformative prospect in itself, but the discovery further suggests that it may be possible to enhance senses in "healthy" people too, truly revolutionizing the way we see the world.4. A Robot Performs Science
By any standard, it was an elementary discovery — the identification of the role of about a dozen genes in a yeast cell. But what made this finding a major breakthrough was the unlikely form of the scientist: a robot. In April, "Adam," a machine designed at Aberystwyth University in Wales, became the first robotic system to make a novel scientific discovery with virtually no human intellectual input. Robots have long been used in experiments — their vast computational power assisted in the sequencing of the human genome, for example — but Adam was the first to complete the cycle from hypothesis to experiment to reformulated hypothesis without human intervention. Interviewed after Adam's experiment appeared in Science, inventor Ross King argued that artificial intelligence had almost limitless scientific potential — and that a computer would one day make a discovery akin to Einstein's special theory of relativity. "There isn't any intrinsic reason why that wouldn't happen," he said. "A computer can make beautiful chess moves, but it's not doing anything special. In my view, that's what's going to happen in science."
5. Breeding Tuna on Land
In Australia, a tankful of southern bluefin tuna — regal, predatory fish prized for their buttery sashimi meat — began to spawn, and they didn't stop for more than a month. "People said, 'It can't be done, it can't be done,' " said Hagen Stehr, founder of Clean Seas, the Australian company that operates the breeding facility. "Now we've done it." Scientists believe that the breeding population of the highly migratory southern bluefin has probably plummeted more than 90% since the 1950s. Others have gotten Pacific bluefin to spawn and grow in ocean cages, but by coaxing the notoriously fussy southern bluefin to breed in landlocked tanks, Clean Seas may finally have given the future of bluefin aquaculture legs.
6. Water on the Moon
There is water on the moon, scientists stated unequivocally in November. Gallons of it. On Oct. 9, NASA used a rocket to punch a hole about 100 ft. across the moon's surface, then measured about 25 gal. of water vapor and ice in the resulting debris. Some scientists speculated that there may be enough water in the craters of the moon's poles to sustain future colonies of astronauts. Others said the ice could hold a historical record of the solar system. NASA said the first priority was to figure out where the water came from and measure how much of it there is. Meanwhile, the discovery had a more immediate and widespread impact among the rest of us: the rekindling of an old thrill. In 2009, the moon, our recently neglected neighbor, regained her mystery.
7. The Fundamental Lemma, Solved
In 1979 the Canadian-American mathematician Robert Langlands developed an ambitious and revolutionary theory that connected two branches of mathematics called number theory and group theory. In a dazzling set of conjectures and insights, the theory captured deep symmetries associated with equations that involve whole numbers, laying out what is now known as the Langlands program. Langlands knew that the task of proving the assumptions that underlie his theory would be the work of generations. But he was convinced that one stepping stone that needed confirmation — dubbed the "fundamental lemma" — would be reasonably straightforward. He, his collaborators and his students were able to prove special cases of this fundamental theorem. But proving the general case proved more difficult than Langlands anticipated — so difficult, in fact, that it took 30 years to finally achieve. Over the past few years, Ngo Bao Chau, a Vietnamese mathematician working at Université Paris-Sud and the Institute for Advanced Study (IAS) in Princeton, formulated an ingenious proof of the fundamental lemma. When it was checked this year and confirmed to be correct, mathematicians around the globe breathed a sigh of relief. Mathematicians' work in this area in the last three decades was predicated on the principle that the fundamental lemma was indeed accurate and would one day be proved. "It's as if people were working on the far side of the river waiting for someone to throw this bridge across," says Peter Sarnak, a number theorist at IAS. "And now all of sudden everyone's work on the other side of the river has been proven."
8. Teleportation!
Inching our reality ever closer to Star Trek's, scientists at the University of Maryland's Joint Quantum Institute successfully teleported data from one atom to another in a container a meter away. A landmark in the brain-bending field known as quantum information processing, the experiment doesn't quite have the cool factor of body transportation; one atom merely transforms the other so it acts just like the first. Still, atom-to-atom teleportation has major implications for creating supersecure, ultra-fast computers.
9. The Large Hadron Collider, Revived
It is largest science experiment ever conducted. The Large Hadron Collider (LHC) at CERN, the European Organization for Nuclear Research, took a quarter of a century to plan and about $10 billion to build. Housed in a 17-mile underground ring, the LHC has been designed to accelerate particles at temperatures colder than that of deep space to a velocity approaching the speed of light. Beset by a series of hiccups and delays, the CERN scientists on Nov. 29 finally recorded a benchmark achievement, powering up a proton beam to an energy of 1.05 trillion electron volts (TeV), overtaking the Tevatron accelerator at Fermilab in Illinois as the world's most powerful accelerator. Eventually the machine will power up to as much as 7 TeV, causing collisions of such high energy that they will re-create the conditions in the seconds after the Big Bang. Amid the by-products of these collisions, physicists will be searching for signs of a hypothetical subatomic particle called the Higgs boson, which according to current theory is responsible for imparting mass to all things in the universe. Other scientists are hoping for even deeper clues, like confirmation of an ambitious theory called supersymmetry. Let the physics begin.
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