Science news of the year.

What's in a Name?

Scientific-classification schemes don't usually make children cry, but I know at least one 5-year-old who was in tears when he heard that Pluto had been struck from the list of true planets. In any science, as fields advance, definitions must be reconsidered, however difficult it is for people to readjust.

Children aren't alone in feeling strongly about Pluto's status. Last June, after the International Astronomical Union announced that it would redefine the word planet, a group of adults formed the Society for the Preservation of Pluto as a Planet. Feelings ran high among astronomers too. A panel proposed a definition on Aug. 16 that would have kept Pluto as a planet (SN: 8/19/06, p. 115), but astronomers attending the union's meeting voted overwhelmingly on Aug. 24 to add a size criterion that relegated Pluto to a less prestigious category: dwarf planet (SN: 9/2/06, p. 149).

Another controversy in 2006 hinged on definition. Time as recorded by the astoundingly accurate atomic clocks doesn't stay in sync with time measured by Earth's rotation. So, what's a year? Timekeepers argue that both measures are useful but haven't agreed when to add leap seconds to make the planetary and the atomic clock years match up (SN: 4/22/06, p. 248).

The boundaries of the category Homo sapiens also received scientific attention this year. A report challenged the 2004 announcement that a fossil find on an Indonesian island represents a new species of tiny relatives of humanity, arguing that the partial skeleton came from an early person with a growth disorder. Some anthropologists adamantly disagreed or noted that it's difficult to delineate who's who among fossil species (SN: 11/18/06, p. 330).

Strong opinions also clashed over whether ants leading nest mates to food warranted the word teaching (SN: 1/14/06, p. 20). And zoologists raised the possibility that birds, like scientists, may debate a word's meaning. A recent report says that chickens use a "tck, tck, tck" to announce a nutritious find, such as corn kernels (SN: 11/18/06, p. 325). Perhaps next year researchers will detect behaviors suggesting that one bird asks another, "You call that food?"

--Julie Ann Miller, Editor in Chief

Anthropology & Archaeology

Mini debate Anthropologists clashed over a report that a partial skeleton initially attributed to a new, tiny species of human cousins actually comes from a pygmy Homo sapiens with a developmental disorder (170: 330).

Ancient genes New techniques enabled scientists to extract an unprecedented amount of DNA from a Neandertal fossil, ushering in a new era of Neandertal genetics (170: 323 *).

An excavation in Africa yielded the oldest and most complete fossil child in our evolutionary family, from a more than 3-million-year-old species (170: 195 *).

Exploration of an ancient, dried-up lakeshore in Australia revealed the largest known collection of Stone Age footprints, made roughly 20,000 years ago (169: 3 *).

Mix it up Genetic analyses suggested that human and chimpanzee ancestors interbred before going their separate evolutionary ways no more than 6.3 million years ago (169: 308 *).

At a prehistoric farming village in Pakistan, researchers discovered the oldest known examples of dental work, 11 teeth with drilled holes dating to between 9,000 and 7,500 years ago (169: 213 *).

Write stuff Researchers concluded that a slab of stone found by road builders in southern Mexico contains the oldest known writing in the Americas, from almost 3,000 years ago (170:179 *).

Back tracks Bones from a 1.8-million-year-old spinal column supported the controversial theory that ancient human ancestors talked to one another (169: 275 *).

Tree trimming Fossils of a 4.1-millionyear-old human ancestor in Africa fueled the idea that early members of our evolutionary family arose one species at a time rather than branching out into many species (169: 227 *).

Old England Investigators who found 700,000-year-old stone tools at a site on England's southeastern coast said that the implements provided the earliest evidence of human ancestors in northern Europe (169: 29).

Sizable find A 260,000-year-old skeleton from China was determined to represent the largest known female among human ancestors and offered insights into the origins of large, broad bodies adapted to cold climates (169:116 *).

Doggone After a rancorous debate, planetary scientists voted to demote Pluto, leaving the solar system with only eight planets (170: 115 *, 149). Another object that's larger than Pluto and was once touted as the tenth planet at the fringes of the solar system was renamed Eris and excluded from 5 planethood (169:26 * 230 *; 170: 237 *). Further blurring the definition of planet were observations of low-mass brown dwarfs (170: 360 *).

Crash cargo In the aftermath of a collision between two galaxies, researchers directly detected invisible dark matter for the first time, they reported (170:131 *).

Big picture The most detailed portrait ever taken of the radiation left over from the Big Bang provided fresh evidence that the universe began with a brief but tremendous growth spurt (169:163 *).

Dark secrets A controversial study hinted that dark energy may not have been constant over time (169: 35). But Hubble Space Telescope observations traced dark energy's fingerprints to earlier in time than ever before and indicated that the energy hadn't varied (170: 323).

Comet collector Analyzing a capsule containing dust collected from the comet Wild-2, scientists found evidence that comet material could have formed only at the fiery temperatures close to the sun and was then widely distributed across the solar system (169: 37,182 * 170: 387 *).

To the moon NASA unveiled a plan to begin assembling a human outpost on the moon in 2020 and finish building it by 2024 (170: 373).

Martian water A Mars-orbiting spacecraft discovered recent color and shape changes on two Martian slopes, a sign that water might have flowed there in just the past few years (170: 416).

Crumbling comet Scores of telescopes recorded the continuing breakup of a comet as it nears the sun (169: 277 *).

Moon jet A spacecraft confirmed that the south pole of Saturn's moon Eneeladus spews jets oficy particles into space (169:13 * 282 *).

Growing up fast When the universe was only one-fifth its current age, a remote galaxy had already begun to look like the modern Milky Way (170:157).

EYE ON SATURN

The Cassini spacecraft captured an image of the most powerful storm ever seen on Saturn (169: 118 *). New evidence indicated that a shattered moon produced the planet's main rings (169: 198). With the sun poised behind Saturn, Cassini discovered two new rings and confirmed the presence of two ringlets (170: 263).

Delayed onset The next solar-activity cycle won't begin until late 2008, a year later than the sun's standard cycle would forecast, a new computer model predicted (169:147 *).

Galactic cannibalism A highly elongated group of stars was revealed to be a dwarf galaxy that the Milky Way is gobbling up (169: 78). About 13 billion years after its birth, our galaxy is still packing on the stars (170: 12).

After several years of uncertainty, NASA gave the go-ahead for a shuttle crew to replace and repair parts on the Hubble Space Telescope (170: 294).

Radio daze Astronomers discovered what appears to be a new class of radio wave-emitting stars (169: 99).

Stellar performance Measuring radioactive material spewed by dying stars, astronomers calculated the star-formation rate in our galaxy over the past few million years (169: 6).

Gravity's lens Astronomers found 19 cosmic mirages, phenomena created when the gravity of a massive galaxy bends and magnifies the light from a background object (169: 45).

Titanic findings The frigid surface of Saturn's moon Titan revealed dunes like those in the Arabian Desert (169: 333). Radar images strongly suggested that the moon holds lakes of liquid hydrocarbons (170: 83 *) and a combination of radar and infrared pictures revealed the moon's tallest mountains (170: 405).

Red Jr. Jupiter developed a second red spot (169: 222* 293; 170: 69, 301).

Watering Earth A newly discovered trio of unusual, icy comets hidden in the asteroid belt appeared to be the primary source of water for early Earth (169: 252).

Big beginning A supernova appeared to have originated with a much heavier star than the standard theory allows (170: 237).

Record-breaking galaxy Astronomers found a galaxy more distant than any other known in the universe (170: 269).

Distant planets Researchers gathered indirect evidence of the smallest planet known to exist outside the solar system (169:126). Scientists confirmed the existence of the nearest known planet beyond the solar system (170: 334), discovered what may be the largest planet ever found (170: 181 *), and measured the temperature variation between the light and dark sides of an extrasolar planet (170: 285).

Planet makers Astronomers discovered a disk that may make planets in the harsh environment surrounding an exploded star (169: 211). Disks with the potential to form planets or moons were found orbiting extrasolar objects that themselves are no heftier than planets (169: 355).

Holes in two Theorists for the first time successfully simulated the merger of two black holes and the event's production of gravitational waves (169: 243).

Recent smash Findings suggested that a small galaxy has just plunged into the Andromeda galaxy, opening a window on collisions that are rare today but were common in the early universe (170: 261).

Rip-off Telescope observations revealed that thermonuclear explosions tore the outer layers from a dense, nearby star within the past 108 years (170: 54 *).

Superfind Bytraining scores of telescopes on a supernova associated with the second-closest-known gamma-ray burst, astronomers confirmed that bursts arise from material blasted into space by supernova explosions (169:133 *).

Cosmic, and big Astronomers discovered the universe's largest known structures (170:141).

Icy small-fry Powerful telescopes detected more than 50 of the tiniest chunks of ice ever discerned in the outer solar system (170: 100).

Galactic origins A halo of hot gas flowing into a massive, spiral galaxy appeared to be a leftover from the galaxy's formation (169: 85).

Birth photo The most detailed portrait ever assembled of the Orion nebula promised to provide new insight about star birth throughout the galaxy (169:154).

Behavior

Monkey mimics Scientists showed for the first time that baby monkeys possess a crucial social skill, imitating facial movements displayed by their caretakers (170:163 *).

Gay clue A study indicated that boys who grow up with older brothers stand an increased chance of becoming homosexual, in a process that perhaps begins before birth (170: 3 *).

Aging well A long-term study of wild chimpanzees found that males prefer to mate with old females, who have demonstrated success at surviving and raising offspring (170: 341).

Anger mismanagement A national survey found that a surprisingly large proportion of people experience recurring, hostile outbursts that include domestic violence and road rage (169: 356 *).

Mellow out Scientists reported that the aging brain restructures itself in ways that encourage emotional stability and a tendency to favor positive emotions over negative ones (169: 389 *).

Hyper kids Long-term data showed that girls diagnosed with attention-deficit hyper activity disorder encounter a variety of problems as teenagers, even as their hyperactivity symptoms diminish (170: 21 *). Another investigation charted a mix of behavioral improvements and side effects in preschoolers who had been prescribed stimulant medication for the condition (170: 275).

Brain scans revealed that children with extremely high scores on intelligence tests show a unique trajectory of brain development, characterized by initial thickening and then by marked thinning of brain tissue (169: 195).

Good trips Evidence suggested that, with proper preparation and monitoring, the psychedelic drug psilocybin triggers life-changing mystical and spiritual experiences in ordinary people (170: 216 *).

Alone together A series of studies probed the workings of Asperger syndrome, an antismlike condition characterized by social awkwardness, repetitive behavior, and narrow interests (170:106).

Buy out A national telephone survey found that nearly 6 percent of adults are compulsive buyers, going on frequent shopping binges that leave them debt-ridden, anxious, and depressed (170: 227 *).

Storm survivors Interviews with Gulf Coast residents suggested that in the year after Hurricane Katrina hit they experienced a surge in mental disorders combined with an undercurrent of personal growth and resilience (170:150).

Bias test Psychologists debated the merits of a popular test of unconscious preferences that, according to some, has uncovered widespread, unacknowledged biases against black people (169: 250).

PRESCRIBING DEBATE

Regulatory action and scientific clashes arose concerning the efficacy and safety of a popular class of anti-depressant drugs, especially in depressed youth (169: 168).

Biomedicine 

Circumcision benefit Two East African trials showed that circumcision protects men from the AIDS virus (170: 405). Mass circumcision of boys and men in sub-Saharan Africa could avert 2.7 million new cases of HIV infection over the next decade, scientists asserted after comparing the distributions of the practice and the infection (170: 77). Circumcision was also found to reduce rates of other sexually transmitted diseases (170: 325).

Macular regeneration A new drug called ranibizumab may enable many people with the eye disease known as age-related macular degeneration to recover some vision (170: 227 *). Variations in two genes could account for three-quarters of all cases of macular degeneration (169: 158). Transplanted retinal cells restored vision in mice with degenerative eye disease (170: 308).

Cancer genetics A study suggested that a mutated BRCA1 gene predisposes a woman to breast and ovarian cancer because progesterone stimulates runaway cell proliferation unless it's held in check by a healthy version of the gene's protein (170: 355 *).

MS advances The multiple sclerosis drug natalizumab got a second chance after being withdrawn in 2005 (169: 131 *). An immune-suppressing drug called fingolimod slowed relapses in MS patients (170: 179).

Alzheimer's Two tests showed promise in detecting Alzheimer's disease or other cognitive impairments years before symptoms arise (169: 102). The drug memantine slowed mental decline in Alzheimer's patients in a 12-month trial (169:110), and a novel drug reversed some Alzheimer'stype symptoms in mice (169: 222). Chronically activated brain areas showed excess amyloid beta, the waxy protein tied to Alzheimer's (169: 3).

Cancer treatments Delivering chemotherapy directly into the abdomen of women with ovarian cancer improved their chances of survival (169: 62). The anti-inflammatory drug celecoxib, currently prescribed mainly for arthritis, prevented precancerous growths in the colon (169: 213). The antiosteoporosis drug raloxifene worked as well at preventing breast cancer as did tamoxifen, the sole drug currently prescribed for this purpose (16.9: 285).

No help Although often prescribed for people with anorexia nervosa, the popular antidepressant medication Prozac offered no better protection against the eating disorder than placebos did (169: 374).

Bird flu Vaccinating people against one strain of avian influenza primed them to rev up a potent defense against another strain (170: 262). By piggybacking components of bird-flu viruses onto an existing poultry vaccine, scientists created vaccines that prevented the disease in chickens (169: 324 *).

CHLOROQUINE'S RETURN

An expensive drug that had lost much of its punch against malaria over the past 20 years showed signs of regaining its strength in the African nation of Malawi (170: 307 *).

A dangerous shift Men who alternate between daytime and nighttime work had triple the average rate of prostate cancer (170: 195). And women exposed to light during the night had reduced concentrations of melatonin in their blood, a decline that supports the growth of breast tumors (169: 8 *).

Added protection Condom use reduced women's risk of being infected with human papillomavirus and of developing precancerous growths on the cervix (169: 387).

Crib death Tests of babies who died of sudden infant death syndrome showed abnormal regulation of the chemical serotonin in their brains (170: 294).

Diabetes People taking antidepressant medication appeared to be at increased risk of developing diabetes (169: 398), and loss of sleep seemed to be a culprit too (169: 195 *). The popular dietary supplement glucosamine didn't cause insulin resistance, the precursor of type 2 diabetes, in test volunteers (169: 398). Two experimental drugs lowered blood sugar significantly in people with type 2 diabetes (169: 398), and a traditional Chinese medicine showed promise as a treatment for the disease (169: 357 *).

Dengue ashore The severe form of dengue fever, dengue hemorrhagic fever, reached the continental United States for the first time (170: 286).

Clot stoppers A decades-old form of the anticlotting drug heparin was as safe, as effective, and potentially as convenient as newer, related anticlotting drugs that are many times as expensive (170:174).

Vaccines Two new vaccines proved safe and effective against life-threatening childhood diarrhea (169: 78). In monkeys, an experimental vaccine prevented infection by the lethal Marburg virus (169: 277).

No go The herbal supplement saw palmetto failed to outperform a placebo when taken for urinary problems (16.9:126).

Bioterror A vaccine against the bioterrorism agent ricin generated antibodies against the toxin (169: 69). Using a submicroscopic packet called a liposome, scientists neutralized anthrax toxin in rats (16.9: 262).

Secondhand smoke Pub workers in Scotland had better respiratory health shortly after a ban on smoking in the establishments went into effect (170: 243).

Demystifying death New methods of assessing a person's risk of sudden death from heart arrhythmia promised to enable doctors to better identify which patients need an implanted defibrillator (170: 202).

Autoimmune switch Using a patient's own stem cells, doctors reversed lupus in severely ill patients (169: 67).

Cool down Antidepressants and some other prescription drugs reduced the number of hot flashes experienced by menopausal women (169: 34.9).

Birthing news High concentrations of a stress hormone in newly pregnant women appeared to make them more likely to have miscarriages (169: 116). Babies conceived between 18 months and 5 years after their mothers' previous births were healthier than babies conceived before or after this period (169: 244).

Heart shock A study showed that in some heart patients, stressful events precipitate changes in blood's composition and flow that may trigger heart attacks (169:157).

Pain revelation An imbalance in signal-carrying immune chemicals might underlie fibromyalgia syndrome, chronic pain without an apparent cause, scientists reported (170:117).

Obesity risks Researchers found that excess weight in middle age hikes a person's risk of heart or kidney problems later in life (169: 21). A large study tied weight gain to heartburn in women (169: 365).

Sleep losses Sleep deprivation emerged as a partial explanation of obesity (169:195 *).

Autism oddity Children born to fathers who are age 40 or older showed an increased risk of developing autism (170:164).

Pathogen judo Scientists have used DNA from the bacterium Clostridium difficile to fashion a vaccine against that microbe (170: 286).

Renal gain The experimental drug roscovitine inhibited polycystic kidney disease in mice (170: 340 *).

Cancer risk New and relatively patient-friendly methods of screening for colorectal cancer showed that they might reduce the malignancy's toll (170:122 *). A study found that a healthy baby faces an increased risk of brain cancer if he or she was born with a large head (169: 93). Computed tomography scans caught lung cancer early in smokers, but questions remained about the procedure (170: 277).

Boosting memory Research in rats showed that an experimental drug regenerates parts of the brain crucial to forming memories (170:101).

Parkinson's advance Parkinson's patients in whom surgeons implanted brain electrodes regained some muscle control and had an improved quality, of life (170:149). A gene found only in men affected the brain's production of dopamine, which might explain why' men are more likely than women to develop Parkinson's disease (169:132).

Leprosy fighter Moxifloxacin, typically prescribed for sinus infections, also showed potency against leprosy (170: 254).

TB touch-up Calculations indicated that existing drugs that take only 2 months to cure tuberculosis, instead of the usual 6 months, could prevent millions of TB infections and deaths (170: 101).

Flip side of aging A biological tradeoff between aging and being resistant to cancer emerged from studies of mice that carry mutant versions of tumor-suppressing genes (170: 296).

Hyperthermia versus cancer By raising a tumor's temperature a few degrees, scientists boosted the efficacy of radiation, chemotherapy, and cancer vaccines (170: 250 *).

Acid test Suppressing stomach acid while taking antibiotics showed the potential of dangerously encouraging drug-resistant bacteria to colonize a person's intestines (170: 269).

To tan and protect A lotion tested on lab mice proved that it could simultaneously stimulate production of the skin pigment melanin and protect the skin against damage from ultraviolet rays (170:196 *).

SOUND THERAPY

No longer limiting the use of sound waves to diagnostic medicine, researchers studied intense, focused ultrasound as a treatment for uterine fibreids, breast cancer, prostate cancer, and other cancers (169: 264 *).

Stroke rehab Stroke survivors having difficulty using an arm or a hand experienced lasting mobility gains after completing an unusual 2-week rehabilitation program (170: 292).

Ear protection A vaccine against common bacteria prevented many ear infections (169:149 *).

Cancer prevention Capsaicin, the component of red pepper that makes it taste hot, killed cancer cells in a test tube and inhibited their growth in mice (169: 254).

Simpler HIV therapy Standard three-drug regimens fought HIV as well as four-drug treatments did, and a drug proved that it might single-handedly maintain a patient's health once the virus is suppressed (170:115).

Leukemia drugs The remarkably successfill cancer drug imatinib (Gleevec) might have caused heart failure in some patients (170: 69 *). Two experimental drugs stopped many cases of chronic myeloid leukemia that are resistant to imatinib (169: 371 *).

Blood to the brain Doctors showed that propping open a clogged neck artery might ease symptoms of depression in elderly people (170: 70).

Bacteria battles Specialized peptides in the urinary tract are the body's first line of defense against bacterial infection, a study indicated (169: 355). A diarrhea-causing microbe became resistant to a widely used class of antibiotics (169: 104 *). A newly recognized compound wiped out some drug-resistant bacteria that cause hospital infections (169: 307 *).

Estrogen therapy Two studies provided conflicting findings on estrogen therapy's effect on breast cancer risk, while a third study suggested that the hormone contributes to blood clot formation (169: 228).

Botany & Zoology

Ape die-off Ebola virus has killed 5,500 western-lowland gorillas in the Republic of the Congo (170: 371 *).

Sniffing vines Experiments showed that seedlings of a parasitic dodder vine find its host plant by following the host's scent, the first evidence that odors stimulate plant growth (170: 214 *).

Big itch An outdoor experiment predicted increases in carbon dioxide in the air and found that poison ivy vines grew bigger and made extra-irritating forms of their toxins (169: 339 *).

Bad timing A study of pied flycatchers found populations shrinking in regions where climate change knocked the foodsupply cycle out of sync with the birds' migration to breeding grounds (169: 276).

Vanishing vultures Veterinarians identified meloxicam as a safe alternative to a painkiller that has poisoned most vultures in India and Pakistan because the birds eat dead livestock dosed with the drug (169: 70). A review of vet records worldwide raised fears that other scavenging birds and other drugs maybe elements of similar disasters (170: 309).

Quick, evolve Researchers found a dramatic example of rapid evolution, a Hawaiian cricket population in which males lost most of their singing behavior within 5 years after the arrival of a predator that follows sounds (170: 197 *). A study of Caribbean lizards likewise found quick changes in leg length--affecting the lizards' speed and climbing skill--soon after a new predator arrived (170: 382).

Hybrid species Two butterflies--a highalpine Lycaeides and a tropical Heliconius-joined the short list of species that researchers contend arose naturally as hybrids of two other species (169:371;170:355).

Extinct or not Birders debated whether the ivory-billed woodpecker survives in Arkansas and agreed only on the need for better evidence (169: 189). The search expanded to other wildernesses, such as an area of the Florida panhandle (170: 285).

NATURAL TEACHERS

Testing suggested that meerkats are true teachers when they ease their pups into the perils of handling live prey (170: 36*) and that tiny British ants teach nest mates where to find food (169: 20 *)

Researchers reported that starlings managed to learn to recognize a grammatical pattern called recursion, once claimed as unique to human language (169: 261). Chickens appeared to be the first animal other than primates to use sounds, as people use words, to represent things in the environment (170: 325 *).

Self-sacrifice versus thuggery A study of territoriality in male side-blotched lizards suggested that their altruism represents a much-discussed scenario in which individuals with a certain version of a gene recognize and favor others with the same form (169: 334).

Why diversity? An analysis of frog evolution showed that species in the tropics don't evolve faster than species in temperate zones, so the extra biodiversity of the tropics must arise some other way (170: 270).

Early bias A study of dawn singing among European birds called blue tits found that the older birds tend to sing earlier and to cuckold sleepyheads (17o: 21).

Decoded Notable genomes unveiled this year included those of the insect-gut bacterium Carsonella ruddii, the smallest yet (170: 285); the black cottonwood, the first from a tree (170; 180); and the western honeybee, the first from an ultrasocial animal with a strictly stratified society (170: 275 *).

Cell & Molecular Biology

Sharing the health Scientists discovered that immune-cell transplants from an extraordinary strain of mice that resists cancer could pass this trait to mice that aren't as lucky (169: 292 *).

See blind mice Researchers prompted mouse-eye cells that aren't normally light sensitive to respond to light, an accomplishment that might eventually lead to treatments for blindness in people (169: 211 *).

Model for madness Scientists genetically altered mice so that they mimic schizophrenic patients in short-term memory and attention deficits (169: 100).

Derailing a disease Injecting a special type of stem cell into dogs with the canine equivalent of Duchenne muscular dystrophy significantly slowed the disease's progression (170: 326).

Hear, hear Tests suggested that the cells responsible for hearing in mammals may be capable of regenerating, as such cells are in birds and some other animals (170:14).

Gender divide Men and women were shown to differ in the amount of protein that thousands of their genes produce (170: 52).

PRION PROLIFERATION

Bad vibrations? Scientists studying pregnant mice suggested that prolonged and frequent use of ultrasound imaging leads to abnormal fetal-brain development (170:99 *).

Fat friends New findings in mice suggested that the collaborative efforts of two common gut microbes can increase the calories that a person extracts from food and stores as fat (169: 373).

Buff and brainy Diet and exercise play important roles in encouraging the brain to function at an optimum level, heal injury, and fight disease, studies continued to indicate (169: 122 *, 136).

Alcohol grows cancer Downing the human equivalent of two to four alcoholic drinks per day dramatically spurred the growth of cancer in lab mice (16.9: 238).

Fit moms, brainy babies Offspring of female mice that jogged each day had a mental advantage over pups of sedentary moms (169:150).

Trimming down cancer Research indicated that fatty, tissue secretes substances that make it hard for the body to battle cancer (170: 277).

It's my metabolism Researchers may have hit on a better way to predict drug toxicity in individual patients: examining their metabolisms, rather than focusing on their genes (169: 244).

Hunger tamer Eating protein appeared to boost blood concentrations of a hormone recently found to restrict appetite, a finding that could partially explain the success of popular high-protein diets (170:173).

Fighting dirty New research found that bacteria that live in dirt are surprisingly resistant to antibiotics, whether or not the microbes had been exposed to the chemicals in the past (169: 109).

Chemistry

Tainted by cleanser Researchers found that 76 percent of an antimicrobial agent exits sewage-treatment plants in sludge used to fertilize farms, a result that raised questions about the fate of the chemical in the environment (169: 275 *).

TOXIC leftovers Bacteria can break down harmful flame retardants called polybrominated diphenyl ethers into evenmore-toxic forms, researchers said (169: 389).

Back on the table? Element 118--first reported in 1999 hut then retracted in 2001-reappeared when nuclear chemists pure reeled californium with 10 million trillion calcium ions (170: 260).

CARBON GOES GLAM

Chemists fashioned tiny dots of carbon that glow in response to light (169: 372 *).

Nanotech safety A field called nanotoxicology took shape as toxicologists and chemists assessed the safety of some engineered nanoparticles (169: 280). Meanwhile, the National Research Council called for more studies of the health and environmental effects of nanotechnology (170: 253).

Leaking lead The water disinfectant monochloramine dissolved lead in laboratory experiments, a finding that might explain increased lead in some drinking-water supplies (169: 333).

Sweet synthesis The efficient synthesis of a renewable chemical building block derived from fructose opened the door to the eventual production of sugar-based polyesters (170: 6).

New in the water Some unexpected byproducts of water-disinfection processes turned up in drinking-water samples from U.S. treatment plants (170: 83).

Catalyst cleans up A new chemical catalyst cleansed water of the pollutant perchlorate, a disrupter of thyroid hormone synthesis in the body (170: 222).

Light-responsive receptor Researchers chemically modified a cell-surface protein to make it respond to light, a feat that scientists could exploit in new studies of brain cells (169: 22).

Gold, bombarded with a laser, formed hollow, namoscale cages similar to carbon buckyballs (169:308).

Chemical coats Chemicals from the exoskeletons of invasive Argentine ants gave scientists some insight into how the insects recognize each other and suggested possible new strategies for controlling them (170: 222).

Recycling allies Researchers found that a tree-rotting fungus can break down an otherwise impervious resin that's commonly used in plywood and fiberboard (170: 29). Other scientists combined a chemical reaction with microbial metabolism to transform polystyrene into a biodegradable polymer (169: 117).

Earth Science

Hot times The average global temperature in 2005 was the highest since scientists began compiling records in the late 1800s (169: 78 *), one possible reason that sea-surface temperatures in the North Atlantic-the birthplace of hurricanes that affect North America and the Caribbean-reached record highs last year (170: 62).

Gassy bugs Microbes deep under the ocean's floor could be the source of some ethane and propane found in sediments, researchers reported (170: 213 *). Analysis of the gases trapped in ancient minerals suggested that methane-generating microbes have been around almost 3.5 billion years (169: 179 *).

Blast survivors Rocks found inside a 70-kilometer-wide crater in southern Africa might be intact pieces of an asteroid that struck the site millions of years ago (169: 292 *).

Nearly naked Ocean researchers found a large area of the South Pacific with almost no seafloor sediment, the result of a combination of factors that probably isn't found anywhere else on Earth (170: 246 *).

Deep-sea action Heavily instrumented undersea vehicles made the first close-up observations of a deep undersea volcano during its eruption (169: 365) and took an unprecedented look at the underside of an Antarctic ice shelf (170: 72 *).

Not so tare Mathematical analyses, backed up by satellite data, suggested that rogue waves are more common in oceans than scientists had previously suspected (170:328 *).

Life down under? Scientists discovered two immense bodies of water trapped beneath Antarctica's kilometers-thick ice sheet and declared that the hidden lakes could harbor life (169: 69 *). Such lakes may not be isolated ecosystems, another analysis suggested (169: 382).

III winds The hurricanes that struck Florida in the summer of 2004 may also have triggered an intense, widespread red tide that afflicted the state's west-central coast throughout 2005, scientists reported (169: 358).

Quake boost A tally revealed that the number of earthquakes that occur beneath surging glaciers in Greenland doubled in the past 4 years (169: 270).

On the fly An analysis of ground motions caused by large earthquakes suggested that it may be possible to estimate the full magnitude of such quakes even before they've stopped rumbling (169:14).

If a large earthquake struck Rome, ground motions could rock the city for up to a minute and threaten many of the city's ancient landmarks, geologists concluded (169: 115).

Researchers analyzing satellite images of the Sahara Desert discovered the region's largest impact crater (169:149).

Going up Molten rock moving through a volcano's plumbing before an eruption can sometimes heat up substantially as it approaches Earth's surface, chemical analysis of lava samples revealed (170:189).

Submarine slumps An oceanographic survey off the northern coast of Puerto Rico found remnants of many underwater landslides, some of which were large enough to have caused deadly tsunamis (170: 30).

Volcanic suppression Ocean cooling caused by the eruption of Krakatoa in 1883 kept a worldwide sea level rise in check well into the 20th century, an analysis of ocean data suggested (169:110).

Shaken, not stirred Dozens of precariously balanced rocks in southern California suggested that earthquakes at nearby faults haven't exceeded magnitude 7 for several millennia (169:164).

Getting the points Physicists created miniature, laboratory versions of towering snow spikes found in the Andes (169: 206) and developed a mathematical model that explains the shape of stalactites (169: 266).

Ancient thermometers The layer of material that formed with age on the surfaces of ancient artifacts made of natural glass revealed the temperatures that the artifacts had experienced (170:110).

Man, old rivers Ocean-floor sediment near England proved to hold material deposited during the last ice age by what was then Europe's largest river system (170: 237). Analysis of South American rocks hinted that the forerunner of the mighty Amazon ran from east to west, the opposite of its flow today (170: 293).

Environment & Ecology

worthless waters A global analysis of marine ecology indicated that the biological riches of the oceans will be spent within a few decades if current fishing trends persist (170: 291).

warming and wildfires Major forest fires in the western United States became more frequent and destructive over the past 2 decades, in step with rising average temperatures in the region (170:19 *).

LONG HAUL

More than half the airborne dust that provides vital nutrients to the Amazonian rainforest comes from a small corner of the Sahara, researchers reported (170: 333).

Dirty secret Recognition grew that soils in many communities are laced with natural but potentially hazardous asbestos (170: 26 *).

Killer warming Data suggested that Earth's rising temperatures might be a factor in the extinction of dozens of tropical-frog species (169:109).

Less than green Emerging data indicated that use of pesticides containing pyrethroids, even by homeowners, poses significant environmental risk (169: 74 *).

New hormones At least some fluorinated water pollutants, such as the nonstick chemical known as PFOA, triggered estrogen-like action in fish (170: 366), and waterborne pesticides with an estrogenic effect impaired protective burrowing behavior in mussels (170: 397).

Plastic and diabetes Exposure to trace amounts of an estrogenlike ingredient of polyearbonate plastic may increase the risk of diabetes, experiments in mice suggested (169: 36 *).

Macho moms Perchlorate, a compound best known as a component of rocket fuel, disrupted sexual development in fish to make females resemble males (170: 99 *).

Invasion infiltration By modifying a technique used to flavor foods, researchers concocted tiny particles that poisoned the invasive zebra mussel (169: 4).

Night light New digital images demonstrated that artificial light from U.S. urban areas penetrates remote wild places, where it may disrupt ecosystems that need a nightly quota of darkness (169: 170 *).

Dirty diesels Just a few diesel-fueled vehicles account for much of traffic-related soot, European data indicated (169:125).

Skin-allergy plasticity Low doses of one of the most commonly used softeners in plastics aggravated dust-mite allergy in test animals (170: 174).

Lavender revolution Two plant extracts that are common ingredients in hair- and skin-care products act like a female-sex hormone, and they caused abnormal breast development in a small group of boys, their doctor reported (170: 6).

Polar bear problem Research linked persistent pollutants with reproductive impairment in polar bears (170:173).

Holy smoke Incense and candles release substantial quantities of pollutants that may harm health, air sampling in a church indicated (170: 116 *).

Methane rising Field studies suggested that Siberian lakes release far more atmospheric methane than had been previously recognized (170:165). A wide variety of plants also appeared to routinely produce methane in significant quantities (169: 19 *).

BAD BEAUTIES

Doscarded aquarium fish appeared to be the source of an alien population of red lionfish that's breeding in the Atlantic Ocean and could threaten economically important fish (170: 168 *)

Food & Nutrition

Longevity juice A constituent of grape juice and red wines increased the life spans and well-being of mice that had been fed fatty diets (170: 293 *).

Fat chance Cutting fat intake after menopause offered women little if any protection against breast cancer, colorectal cancer, or heart disease, a massive, 8-year trial found (169: 85).

COFFEE CHASER cups of coffee may provide heavy drinkers with some protection against cirrhosis, a liver-scarring disease common in alcoholics (169: 397).

Food for thought Senior citizens who eat a Mediterranean-style diet rich in plant matter and fish, low in saturated fat--were less likely than their peers were to develop Alzheimer's disease (169: 245).

Antibiotic vitamin Because vitamin D turns on a major germ killer in the body, a deficiency in the nutrient may leave people especially vulnerable to infections (170: 312 *).

Satiety buster A protein that's more abundant in the blood of obese people inactivated leptin, a hormone that controls hunger (169: 252).

Grapefruit's culprit Researchers found the natural compounds in grapefruit juice that are responsible for its unwanted chemical interaction with many drugs (169: 317).

Snack center Gene activity in mouse brains led researchers to a body clock that appears to be regulated by food (170:109).

Safe seeds Scientists engineered cotton plants whose seeds lack a toxin that had previously made them inedible (170: 339 *).

Low-protein therapy A diet low in protein improved the effectiveness of drug therapy and abbreviated the most debilitating symptoms suffered by Parkinson's disease patients (169:158).

Prion latency A rare but deadly human illness spread by cannibalism has an incubation period in some individuals of about 4 decades, researchers in New Guinea discovered (170: 45).

Mathematics & Computers

All square Mathematicians nailed down when it is possible to express numbers as the sums of squares (169:152 *).

Chaotic bites A new, physics-based approach to analyzing simple games, such

as Chomp and Nim, revealed changing geometric patterns reminiscent of crystal growth (170: 58 *).

Medal work Fields Medals were awarded to four mathematicians, including Grigori Perelman, who proved a famous conjecture about the shapes of higher-dimensional spheres (170:132).

Messy packing Physicists found that, in high dimensions, disorderly spheres pack together more densely than orderly arranged spheres do (170: 244 *).

Hairy calculations New algorithms improved the rendering of blond hair in computer-generated animations (170: 68 *).

Phone drain In a new type of cyberattack, assailants using computers connected to the Internet secretly induced distant cell phones to rapidly deplete their batteries (170:190).

A remarkable geometric shape made up of a sequence of triangles led to a host of novel forms and mobile structures (170: 266 *).

Mathematical models helped explain how group behavior is more than the sum of its parts (170: 347 *).

Paleobiology 

Found link Fossils from Greenland provided researchers with new insights into ancient vertebrates' move from water to land (169: 379).

Sticky subject Remnants of a spider web embedded in ancient amber hinted that some spiders' diets haven't changed much in millions of years (169: 390 *).

Tiny treasure A small chunk of amber found in Southeast Asia displayed the remains of a bee that's at least 35 million years older than any reported fossil of a relative (170: 334).

Extreme necking Paleontologists unearthed the remains of a massive, plant-eating dinosaur whose neck might have been twice as long as its body (169: 270 *).

Like clockwork Discovery of the sudden appearance of many new species of rodents in Chile about 18 million years ago indicated when the southern Andes rose (170: 318).

Sight for dinosaur eyes A study of dinosaur eyes suggested that Tyrannosaurus rex had sophisticated vision that might have enhanced its predatory prowess (170: 3 *).

DNA revelation Genetic analyses of the remains of gray wolves found in Alaska indii cared that a distinct subpopulation of that species disappeared at the end of the last ice age (170: 318).

Legging it Archaeopteryx, the earliest known bird, had feathers on its legs that might have provided lift for flight and improved its maneuverability (170:197 *).

Rarity explained? Growth rings in fossilized bones suggested that many juvenile tyrannosaurs survived to adulthood, which could explain why paleontologists have unearthed so few remains from young members of such species (170: 78).

Ancient forest Fossils trapped in amber provided evidence that the Amazonian rainforest is up to 15 million years old (170: 150 *).

Battle scats Damage in the fossil tusks of adult-male mastodons suggested that the creatures engaged in fierce combat with rival males at a certain time each year (170: 276 *).

CRESTED BEAUT 

The oldest known member of the tyrannosaur clan, a 3-meter-long predator that lived in China about 160 million years ago, has a fragile bony crest on its skull, scientist reported (169: 83*).

Physics

See saw Theorists proposed ways to make invisibility cloaks (170: 42 *). Then, experimentalists demonstrated a prototype that hides an object from microwave sensors (170: 261 *).

Shrinkage Differences between the amount of radiation that hydrogen molecules absorbed in a lab and in space suggested that mu, a supposed constant of nature, shrank in the past 12 billion years (169: 259 *).

Slicker ticker An atomic clock using high-frequency ultraviolet radiation tracked time more precisely than do the lower-frequency microwave clocks that have been the world's standard for 50 years (170: 51 *).

Critics claimed in books, articles, and blogs that string theory--which proposes that infinitesimal strands of energy are the universe's building blocks--has failed because it doesn't make testable predictions (170: 264).

Go with the flow Adding boron changed the widely used semiconductor silicon into a superconductor (170: 341). Meanwhile, an advanced superconductive wire carried large currents in magnetic fields of practical strength (169: 196 *).

Warmth welcome An exotic quantum state, which is called a Bose-Einstein condensate and was previously produced only at ultracold temperatures, made its room-temperature debut (170: 211 *).

Bit by bit In advances toward quantum computing: A new microchip manipulated a single ion (169: 5), quantum states passed from light to atoms (170: 301), and a computer found answers without actually running (169: 117 *).

Flip responses Physicists probed a previously unrecognized way that electric currents flip or rotate polarizations of nanomagnets--then used the trick in prototype memory chips and microwave transmitters (169: 11).

Highly rated A scheme that uses electrons as energy absorbers cranked up the particle-collision rate in the world's highest-energy collider and could soon find use in other major particle accelerators (169: 68).

On the dot When exposed to light, nanocrystals called quantum dots unleashed a remarkable abundance of electrons, a feature that might lead scientists to improved solar cells (169: 344 *). Ancient Greeks unwittingly used quantum dots in hair dye, analysis of an ancient written formula indicated (170: 350).

Hard air X rays revealed unexpected four atom groupings in highly compressed, solidified oxygen (170:182). Under intense pressure and heat, carbon dioxide became a transparent solid that's the hardest known glass (169: 374).

Science & Society

Faked finds Investigators reported that a South Korean scientist faked embryonic-stem-cell findings (169: 20).

Depoliticizing science A new law banned three federal agencies from knowingly disseminating bad data or using political litmus tests to select expert advisers (169: 62).

Doors shut Some Environmental Protection Agency libraries began permanently closing because of large proposed cuts to their funding (170: 35).

Evolution debates Arguments between supporters of evolution and of intelligent design heated up in the courts, state legislatures, and communities (169:120).

Peer prejudice A study revealed evidence of bias when scientists review research papers identified by the authors' names and affiliations (169: 285).

VENTING CONCERNS

Scientists developed a code of conduct to guide research and other activities at hydrothermal vents (107: 232 *)

NASA overextended A National Academy of Sciences study joined a chorus of critics claiming that NASA has been sacrificing basic science to finance the International Space Station and to return astronauts to the moon (169: 317).

Technology

Tag team Prototype electronic labels made of plastic responded to a commercially usable radio frequency, a step toward ubiquitous radio tags for merchandise (169: 83 *). In a test, other radio tags prevented surgeons from leaving surgical sponges in patients (170: 77).

Bright future New indoor-lighting schemes tapped sunlight and energy-efficient light-emitting diodes (169: 314 *). Encircling a light-emitting diode with concentric, nanoscale ridges brightened it seven-fold (170:125).

Puny powerhouses Crawling bacteria ran a micromotor (170:147 *). Munching bacteria in novel fuel cells made electricity for sensors, a hint that the cells might someday generate sufficient power from sewage to operate wastewater-treatment plants (169: 72).

Vision revision Prototype eyeglasses that might someday replace bifocals switched focus in response to electricity (169: 243 *).

Robo de novo Among robotics advances, artificial muscles powered themselves chemically (170: 8 *), a new membrane detected textures with human-skin sensitivity (170: 14), and an innovative algorithm enabled a machine to adapt to damage (170: 324 *).

By Zeus An X-ray and optical study revealed nearly all the parts and their probable uses in an ancient Greek astronomical computer, the Antikythera mechanism (170: 357 *).

Better bladder Bioengineered bladders performed well in seven young patients, making the bladder the first successful labgrown internal organ for people (169: 214).

Slick findings Grooved oil skimmers collected up to three times as much spillage as smooth skimmers did (170: 325). Crude oil zapped by electromagnetic fields turned runny, potentially easing its flow through pipelines (170: 285).

Freeze-dried pearl A ceramic composite fabricated mainly by simple freezing had a microstructure featuring nearly the strength and toughness of mother-of-pearl (169: 51 *).

Hey you, tubes Carbon nanotubes squished hard metals inside them (169: 326 *) and detected deterioration of engine oil (170: 126). Meanwhile, centrifugation sorted carbon nanotubes by size and electronic properties (170: 244).

In steps toward creating optical circuits that might be better than electronic ones, researchers unveiled a prototype laser for silicon microchips (170: 198) and slashed power losses in silicon optical amplifiers (770: 22).

Wearable rice Textile scientists extracted natural cellulose fibers from otherwise useless rice straw and spun it into yarn (170: 222).

What genes? Increasingly prized as structural components, DNA strands formed stable, complex geometric shapes (1629: 165, 174) and a "nanometronome" (169: 141).

Take a breather A prototype system that greatly decreases automobiles' toxic-hydrocarbon releases passed road tests (170: 206).

Food for Thought

Born to love salt Research indicated that biological programming in the womb can foster a taste for salty foods (sciencenews.org/articles/20060128/food.asp).

Chocolate sunscreen A cocoa drink rich in flavonoids not only made women's skin look better but also protected it from sunburn (sciencenews.org/articles/20060610/food.asp).

Pressure washer Pressure-cooking reduced to safe concentrations a liver carcinogen that can taint rice (sciencenews.org/articles/120060415/food.asp).

Germ bodyguards Ubiquitous waterborne protozoa appeared to support several types of bacteria responsible for gutwrenching food poisoning, researchers found (sciencenews.org/articles/20060318/food.asp).

Lightly processed New studies found that trace constituents of virgin olive oil, aside from its heart-friendly fats, fight cardiovascular disease and cancer (sciencenews.org/articles/20061014/food.asp).

Satiety fraud Diluted calories are far i more effective at satisfying hunger than are calorie-dense products, studies demonstrated (sciencenews.org/articles/20060218/food.asp).

Gender differences Young women's advantage over young men in heart disease risk may trace in part to different responses to fats in the first hours after a meal (sciencenews.org/articles/20060902/food.asp).

Gaining tolerance A new analysis found that most people who suffer from lactose intolerance can still consume milk and other dairy products in moderation (sciencenews.org/articles/20060408/food.asp).

FRUITY RELIEF

Certain fruit products, such as cherry juice, appeared to reduced pain and speed people's recovery from muscle injury (sciencenews.org/articles/20060701/food.asp).

Cola break? Regularly consuming cola-flavored drinks appeared to weaken bones in postmenopausal women, leaving them vulnerable to fractures (sciencenews.org/articles/20061028/food.asp).

With the grain Data suggested that diets rich in whole grains ward off a type of gum disease (sciencenews.org/articles/20060624/food.asp).

MathTrek

Record numbers Computers at Central Missouri State University identified the 43rd and 44th Mersenne primes (sciencenews.org/articles/20060114/mathtrek.asp).

Crashing cars Data analyses showed that men, whether as drivers or pedestrians, have a much higher rate of traftic fatalities than women do (sciencenews.org/articles/20060415/mathtrek.asp).

Magic counting A physicist established that Benjamin Franklin's remarkable magic squares are just three of more than a million possibilities (scieneenews.org/articles/20060624/mathtrek.asp).

Soccer geometry In a break with recent tradition, the official ball used in the 2006 World Cup was made from 14 curved panels (scienecnews.org/articles/20060708/mathtrek.asp ).

Class size An analysis showed that computing the average size of classes at a college can give different answers that depend on one's point of view (sciencenews.org/articles/20060812/mathtrek.asp).

Web links Pioneering studies of social networks and the Web's structure won Jon Kleinberg a prestigious computer-science prize (scieneenews.org/articles/20060826/mathtrek.asp).

Protein knots Researchers found that knotted proteins are rare, but the knots have biological implications (sciencenews.org/articles/20061014/mathtrek.asp).

Yesternet mining Digital records enabled social scientists to study online communities and the diffusion of innovation (sciencenews.org/articles/20061028/mathtrek.asp).

Fibonacci's flowers A biologist examined why the number of petals on a flower isn't always a Fibonacci number (sciencenews.org/articles/20060603/mathtrek.asp).

Upgrading scorer Mathematicians found that it can be tricky to determine which scores to drop when computing a final grade that is to a student's greatest advantage (sciencenews.org/articles/20060610/mathtrek.asp).

Amazing tooth Researchers found that the narwhal's long tusk might sense changes in water temperature and pressure, helping the sea animal survive in the Arctic (sciencenewsforkids.org/articles/20060125/Feature1.asp).

Coral gardens An expedition to an undersea mountain revealed large corals, brilliant sponges, and other strange sea creatures (sciencenewsforkids.org/articles/20060301/Feature1.asp).

Space stuff A spacecraft brought comet grains and stardust back to Earth (sciencenewsforkids.org/articles/20060215/Feature1.asp).

Atomic drive Chemists assembled atoms into tiny molecular cars that motor across a gold surface (sciencenewsforkids.org/articles/20060823/Feature1.asp).

Sahara cemetery Archaeologists uncovered the remains of a Stone Age settlement in the Sahara Desert (sciencenewsforkids.org/articles/20060809/Feature1.asp).

What babies know By studying how babies choose objects, researchers discovered that babies are especially good at learning things that are essential for survival (sciencenewsforkids.org/articles/20060322/Feature1.asp).

Pumping microbes High gas prices focused attention on the use of bacteria to turn waste material from plants into biofuels (sciencenewsforkids.org/articles/20060412/Feature1.asp).

Strangely warm Spacecraft observations suggested that Saturn's mysterious moon Enceladus might have liquid water close enough to its surface to produce giant geysers (sciencenewsforkids.org/articles/20060419/Feature1.asp).

Flu patrol Scientists prepared for a possible flu epidemic (sciencenewsforkids.org/articles/20060104/Feature1.asp).

Endless summer Researchers discovered that a small seabird makes the longest known migration flight (sciencenewsforkids.org/articles//20060517/Feature1.asp).

Snow traps A prize-winning science fair project focused on how snow fences create snowdrifts and increase water supply (sciencenewsforkids.org/articles/20060607/Feature1.asp).

Robot dance Student-built robots played soccer, danced, or went on a rescue mission (sciencenewsforkids.org/articles/20060510/Feature1.asp).