It’s an enduring enigma in paleoanthropology: when and where did modern human behavior arise? The fossil record suggests that anatomically modern humans appeared in Africa sometime between 150,000 and 100,000 years ago. Yet the earliest convincing indications of behavioral modernity in our species, archaeologists have argued, date to tens of thousands of years later and have turned up in Europe, not Africa. With that in mind, some theorists posited that modern behavior blossomed late and rather sudd
Ultra-minaturized electrical components could shrink supercomputers.
Researchers in the Netherlands and the United States have constructed simple computer circuits with electrical components many times smaller than those on commercial silicon chips 1 , 2 . These ultra-minaturized logic circuits hold out the prospect of hand-held computers as powerful as today’s state-of-the-art supercomputers.
Cees Dekker and co-workers at the Delft University
Scientists are finally beginning to understand how common genetic differences among individuals underlie differences in the structures that make up their brains. In the first attempt to actually map these variations, neurologist Paul Thompson and colleagues at the University of California at Los Angeles have discovered that brain structures related to cognitive ability and language seem to be under tight genetic control. The group’s findings, which could help explain how diseases like schizophre
New catalyst means greener paper is not pulp fiction.
Pollution from paper production could be cut, say US chemists, with a new way of refining wood pulp 1 . But the process must go through the mill before it can convert industry.
During paper production, gluey wood component lignin is stripped out to leave stringy cellulose. The harsh chemicals used create environmental pollutants, such as toxic and long-lasting chlorinated compounds.
A new chemical
Our brains use angular measurements to decide how far away objects are.
Even if trigonometry wasn’t your strong suit in school, your brain uses it constantly. You judge distance by measuring the angle between the ground and your line of sight to an object, a new study shows. The finding could improve the design of robots and artificial vision systems 1 .
Volunteers who looked through prisms that increased this angle thought objects were closer than they reall
A microelectronic sensor may alert doctors to bacterial hazards.
Smart bandages could soon alert doctors to the presence of certain bacteria in a wound by glowing different colours. Researchers in the United States have created a tiny device that emits faint light of two colours in response to two types of bug 1 .
Benjamin Miller, of the University of Rochester in New York State, and colleagues hope that a refined sensor might ultimately generate an instant an
Air lets water droplets skim across the kitchen sink.
Scientists have found the answer to a question pondered over many a kitchen sink: why do little droplets skim across the surface of washing-up water rather than mix with it?
Yacine Amarouchene and colleagues at the University of Bordeaux in Talence, France have discovered that the height from which the drops fall has no effect on their lifespan 1 .
Soap, detergent – and indeed food grease – are ’
Mosquitoes’ evolve rapidly in response to global warming.
Mosquitoes are holing up later as winters get warmer, US ecologists have shown. This is the first genetic adaptation to global warming to be identified. Less flexible animals could face extinction, they warn.
The North American mosquito Wyeomyia smithii uses shortening day length to judge when to bed down for the winter. Modern mozzies wait nine days more than their ancestors did in 1972, William Bradshaw and Christin
Solar cells printed like wallpaper.
Solar cells might one day be produced by the roll, as cheaply and easily as wallpaper. Scientists in Arizona are using screen-printing, a technique developed for patterning fabrics, to produce plastic solar cells 1 .
The technique is another step towards the general availability of solar power from flexible devices on plastic sheets or glass panels. The basic materials of a photovoltaic cell are inexpensive, but combining t
Scientists can coax tiny metal particles to self-assemble into microscopic wires that conduct electricity and repair themselves, new research reveals. Kevin D. Hermanson of the University of Delaware and his colleagues, who published their finding in the current issue of Science, suggest that such nanowires may prove useful for wet electronic and bioelectric circuits.
The researchers placed particles of gold ranging in diameter from 15 to 30 nanometers in a fluid suspension within a thin ch
Examine any depiction of Ice Age life and you’re likely to find at least one—a woolly mammoth, that is. But popular appeal notwithstanding, the evolutionary history of this prehistoric beast has proved somewhat difficult to pin down. To that end, findings published today in the journal Science provide some much needed insight.
Working from an extensive Eurasian fossil record going back some 2.6 million years, Adrian Lister of University College London and Andrei V. Sher of the Russian Acad
Some galaxies may have torus envy, if a new study is any indication. The most sensitive imaging yet of nearby galaxy M87’s core reveals that the black hole residing there has either a nonexistent or much fainter ring of dust around it compared with its peers. Scientists had thought that these rings were key features of such highly energetic galaxies. The puzzling finding appears today in the Astrophysical Journal Letters .
The current model of active galaxies such as M87 posits that
Water trapped for millions of years gives a glimpse of oceans’ turbulent past.
Drops of sea water entombed within salt crystals millions of years ago are giving researchers a glimpse of ancient oceans. The water, trapped during evaporation, reveals that the seas have seen large chemical changes during their history.
“The consensus had been that sea-water chemistry hadn’t changed that much over the past 600 million years,” says geochemist Juske Horita of Oak Ridge National La
Dazzling snapshots show how ions power nerve signals round the body.
“Potassium channels underlie all our movements and thoughts,” says Rod MacKinnon of Rockefeller University in New York. His team has now unravelled the molecular mechanics of these minute protein pores. Some say the work merits a Nobel Prize.
Potassium (K + ) channels power the transmission of nerve signals through the body and the brain by ushering K + ions in and out of our cells. MacKin
Humans learn water-gathering trick from bumpy beetle.
A desert beetle turns fog into drinking water with its wings, new research reveals. Materials mimicking the insect could help humans survive harsh environments.
Southwest Africa’s Namib Desert is one of the hottest and driest places on Earth. There is no rain, but on about six mornings a month a fog blows in off the Atlantic and across the land at gale force.
The beetle Stenocara traps this fleeting resour
Half a century of thinning ice leaves Greenland’s future looking wet.
There is new evidence that the Greenland ice pack is in retreat. The finding may be a foretaste of still more rapid melting, and in turn, rising sea levels.
The ice sheet over northwest Greenland has thinned by 10-15 cm a year over the past 40 years, two scientists calculate 1 . The trend indicates “a significant long-term thinning”, says one, Niels Reeh, of the Technical University of
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