By DAVID PERLMAN, San Francisco Chronicle

Stanford University engineers report they have developed a device for computers that can send information over light beams faster than anything yet achieved, while consuming far less energy.

The device, they say, may well overcome the two biggest obstacles to the future of high-speed computing.

BERKELEY, Calif. - One day in the not-too-distant future, we might be filling our cars with fuel made from useless grass.

A biologist at the University of California, Berkeley, has transferred a gene from a variety of corn into a widespread, fast-growing species of the grass, and transformed it into what could become an important source of biofuel.

SAN FRANCISCO - The ocean floor off the coast of Northern California and southern Oregon reveals a record of massive earthquakes that have hit the region over the past 10,000 years -- and there's a 1-in-3 chance that another could strike again within the next 50 years, scientists say.

SAN FRANCISCO - Chimps do it, birds do it, and now it turns out that fish do it, too -- they all use tools of one kind or another to catch whatever they need to eat.

SAN FRANCISCO - Long, long ago, a bold race of early modern humans left Africa and migrated across vast stretches of southern Asia to Australia -- a mass migration of humankind that was followed thousands of years later by a second wave of African migrants who would settle all of Europe and the northern reaches of the Eurasian continent.

PALO ALTO, Calif. - Physicists probing the sun's deep interior have predicted the emergence of sunspots on the surface a full two days before they appear, providing the first early warning of the violent solar storms that can endanger astronauts in space, disrupt electric power grids on Earth, and plunge cities into darkness.

SAN FRANCISCO - The blood-sucking talents of vampire bats are giving scientists new insights against some of the most painful nervous system disorders that humans can suffer.

A spacecraft named Dawn has begun a yearlong visit to the brightest asteroid in the distant sky to study how Earth and its closest planets formed more than 4 billion years ago.

SAN FRANCISCO - The massive gray whales that migrate each year between Alaska's Bering Sea and Baja California have survived thousands of years of sea-level and climate change by altering the way they live and feed, scientists at the University of California, Berkeley have found.

The southern end of the San Andreas Fault may be overdue for a large earthquake that could heavily damage the Los Angeles area, scientists have concluded after studying a record of ancient quakes and flooding around the seismically active region of the Salton Sea.