Human Origins Recede In Australia

People inhabited Australia at least 116,000 years ago, long before prior estimates of that continent's colonization, and they left behind the earliest known examples of rock art.

Detecting a sound heartbeat

Patterns in the lengths of the intervals between heartbeats help researchers distinguish between healthy and ailing hearts.

Life in the Jurassic: Stability amid chaos

"Divided we stand" may be an appropriate motto for a loose-knit community of Jurassic bivalves that weathered tough times.

Ocean bacteria need iron with dinner

Iron regulates the growth of oceanic bacteria, increasing the efficiency with which these microorganisms use carbon.

Rods enhance superconductor performance

Adding tiny magnesium-oxide rods to a superconductor increases its ability to carry current without resistance by a factor of 10.

How many genes does a bacterium need?

A mere 256 genes are considered necessary and sufficient for the basic operations of a modern-day bacterial cell.

New multiple sclerosis drug clears hurdle

The search for a synthetic molecule that could provoke an immune response led to a new drug for multiple sclerosis that soon may be marketed in the United States.

'Clean' water may infect swimmers

The presence of sewage contaminants in seawater may increase bathers' risk of developing a respiratory disease or an ear infection, even when the measured concentrations of fecal bacteria do not exceed government limits.

Research Notes:

Biology:

Live long and prosper

Tubeworms, marine animals dependent on internal bacteria for energy, follow different lifestyles at hydrothermal vents than at sites where oil and gas seep out of the ocean floor.

Tackling sleeping sickness from within

To kill the disease-causing parasite that tsetse flies often transmit to humans, investigators are trying to genetically engineer bacteria found inside the insects.

A nicer side of a bacterial enzyme

Vibrio fischeri, a bacterium that lives harmlessly inside squid, secretes enzymes that investigators had always assumed caused illnesses.

Partners for life . . . and perhaps death

Aphids depend upon bacteria living inside them to supplement a diet short of amino acids, but a gradual buildup of mutations in the bacteria may be destroying this unusual symbiosis.

Physics:

Atomic scouring to dissolve a surface

Just as washing a pot makes it easier to wash away a baked-on crust, pressing on a crystal's surface with the sharp tip of an atomic force microscope can hasten dissolution.

Bringing nanomagnets into quantum step

At extremely low temperatures, a crystal made up of a large number of tiny magnetic clusters displays evidence of macroscopic quantum behavior.

Technology:

At the tone, the time will be. . .

The National Institute of Standards and Technology plans to boost the power of its time signal radio broadcast next year, paving the way toward clocks, wristwatches, and VCRs that can pick up the signal and set the time themselves.

Imaging method really shows some nerve

A noninvasive imaging technique based on magnetic resonance can help doctors distinguish normal nerves from damaged ones, especially in cases difficult to diagnose by traditional means.

Articles:

Interplanetary Odyssey

Can a rock journeying from Mars to Earth carry life?

Frozen or dormant lifeforms could survive the 10 million or fewer years that it may take a fragment of Mars to travel to Earth.

Allegations of Cancer

Does a herpesvirus cause an AIDS-related tumor?

Evidence mounts that a herpesvirus may be responsible for Kaposi's sarcoma.

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