Tiny specks of carbon discovered in 3.85-billion-year-old rocks indicate that life on Earth arose far earlier than previously thought and in a period of asteroid bombardment.

Christopher Chyba
Department of Planetary Sciences
University of Arizona
Tucson, AZ 85721-0092

John M. Hayes
Woods Hole Oceanographic Institution
MS8
360 Woods Hole Road
Woods Hole, MA 02543-1539

Heinrich D. Holland
Department of Earth and Planetary Sciences
Harvard University
Cambridge, MA 02138

Stephen Mojzsis
Scripps Institution of Oceanography
University of California, San Diego
La Jolla, CA 92093-0220

On Mars:

A British team announced that the abundance of organic compounds in a young Martian meteorite, as well as their isotopic ratio of carbon-13 to carbon-12, suggests bacteria may have thrived on Mars as recently as 600,000 years ago.

Grady, M.M., C.T. Pillinger, and I.P. Wright. 1996. Meeting on the possibility of life in the solar system. Royal Society, London.

Amato, I. 1989. Meteorite may carry organic Martian cargo. Science News (July 22):53.

Cowen, R. 1996. Interplanetary odyssey. Science News 150(Sept. 28):204.

_____. 1996. Meteorite hints at early life on Mars. Science News 150(Aug. 10):84.

McDonald, G.D., and J.L. Bada. 1995. A search for endogenous amino acids in the Martian meteorite EETA79001. Geochimica et Cosmochimica Acta 59(6):1179.

Wright, I.P., M.M. Grady, and C.T. Pillinger. 1989. Organic materials in a Martian meteorite. Nature 340(July 20):220.

Lens gets X rays to a point

An aluminum lens focuses high-energy X rays to a spot only a few micrometers wide.

Anatoly Snigirev
European Synchrotron Radiation Facility
B.P. 220
F-38043 Grenoble Cedex
France
E-mail: snigirev@esrf.fr

Deadly Ebola virus seen to thrive in bats

By inoculating jungle-dwelling animals and plants with lethal Ebola virus, researchers have shown that healthy bats may harbor the virus, whose source in nature remains a mystery.

Peter Jahrling
U.S. Army Medical Research Institute for Infectious Diseases
MCMR-UIZ-E
Fort Detrick
Frederick, MD 21702-5011

Thomas G. Ksiazek
Special Pathogens Branch
Centers for Disease Control and Prevention
1600 Clifton Road
Atlanta, GA 30333

Depression fails to scar personality

A long-term study finds that people who suffer an initial episode of major depression do not experience lasting personality changes, such as becoming more introverted or dependent on others.

Kenneth S. Kendler
Department of Psychiatry
Medical College of Virginia
Box 710
Richmond, VA 23298

M. Tracie Shea
Department of Psychiatry and Human Behavior
Brown University School of Medicine
Duncan Building
700 Butler Drive
Providence, RI 02906

Ant life: It's a sister-eat-brother world.

To increase the chances of passing their genes on to future generations, some female ants seem to kill off male siblings.

Liselotte Sundström
University of Helsinki
Department of Ecology and Systematics
Post Office Box 17
FIN-00014
Finland

Research Notes:

Astronomy:

Hailing Hale-Bopp

After a fallow period this spring, in which it looked like Comet Hale-Bopp might prove a fizzle, the icy body has become more active, so it still may be the most dramatic comet of the century when it nears Earth next March.

Harold A. Weaver
Department of Physics and Astronomy
Bloomberg Center
Johns Hopkins University
Charles & 34 Streets
Baltimore, MD 21218

Biology:

Does parenting or prolactin hit first?

The hormone prolactin appears to direct some birds to take on parenting responsibilities for their relatives' offspring.

Stephan J. Schoech
Department of Biology
Indiana University
Bloomington, IN 47405
E-mail: sschoech@indiana.edu

Birds keep close track of seed business

Chickadees replace missing seeds from their winter food caches on almost a one-for-one basis.

Jeffrey R. Lucas
Department of Biological Sciences
Purdue University
West Lafayette, IN 47907
E-mail: jlucas@bilbo.bio.purdue.edu

Behavior:

Out-of-order memories

The act of trying not to think about an episode, such as a traumatic experience, makes it difficult to remember the sequence in which events occurred and may lead to a repression-like memory loss.

Daniel M. Wegner
Department of Psychology
Gilmer Hall
University of Virginia
Charlottesville, VA 22903

Anatomy of apprehension

The amygdala, an almond-shaped brain structure, appears to specialize in picking up signs of threat and danger in the social world, according to a new brain-scan investigation.

Raymond J. Dolan
Wellcome Department of Cognitive Neurology
Queen Square
London WC1N 3BG
England

Biochemistry:

Molasses recruit bacteria for cleanup

Mixing molasses with TNT-contaminated soil spurs bacteria to break down the explosive into harmless molecules.

Mark Hampton
U.S. Army Environmental Center
SFIM-AEC-ETD
Building E4430
Aberdeen Proving Ground, MD 21010-5401
E-mail: mlhampton@aec2.apgea.army.mil
Website: http://aec-www.apgea.army.mil

John Manning
Environmental Research Division
Argonne National Laboratory
9700 S. Cass Avenue
Argonne, IL 60439-4843
E-mail: jfmanning@anl.gov

Magnetic bacteria probe for proteins

Scientists have hitched antibodies to tiny magnetic particles made by bacteria in order to pull proteins out of a solution.

Tadashi Matsunaga
Department of Biotechnology
Tokyo University of Agriculture and Technology
2-24-16 Nakacho, Koganei
Tokyo 184
Japan
E-mail: tmatsun@cc.tuat.ac.jp

Jim Richey
PerSeptive Biosystems
500 Old Connecticut Path
Framingham, MA 01701
Website: http://www.pbio.com

Articles:

The Mother Lode of Natural Gas

Methane hydrates stir tales of hope and hazard

Vast deposits of frozen methane beneath the seafloor could be the fuel of the future.

William P. Dillon
U.S. Geological Survey
Woods Hole, MA 02543

James P. Kennett
Marine Science Institute
University of California, Santa Barbara
Santa Barbara, CA 93106

Keith A. Kvenvolden
U.S. Geological Survey
MS 999
345 Middlefield Road
Menlo Park, CA 94025

Gordon MacDonald
International Institute for Applied Systems Analysis
A-2361 Laxenburg
Austria

Charles Paull
Geology Department
University of North Carolina
Mitchell Hall 029-A
Chapel Hill, NC 27514

Gastrointestinal Blues

Research finds bugs that inflame the human gut

Microbes may cause gastrointestinal inflammation in people who are genetically susceptible.

Robert Greenstein
Laboratory of Molecular Surgical Research
Veterans Affairs Medical Center
Bronx, NY 10468

Balfour Sartor
Division of Digestive Disease
Burnett-Womack Building
University of North Carolina
Chapel Hill, NC 27599