News Briefs15 Million-Year-Old Skeleton May Offer Clues on Human Evolution THE WASHINGTON POST -- A 15 million-year-old skeleton unearthed in Kenya belongs to a previously unknown animal type that may be a sort of great-uncle of our oldest direct relative, scientists say.
The recent find predates by several million years the long-sought “holy grail” of paleoanthropology: the last common ancestor that great apes and humans had before each of those groups diverged and developed separately.
But the new and unexpectedly copious remains are an important step in the search, apparently ruling out one leading candidate for that illustrious evolutionary position, and narrowing the range of characteristics for which fossil-hunters will look.
The partial skeleton, extracted from a stone formation after a protruding tooth first signaled its presence in 1993, came from an animal approximately “the equivalent of a large modern male baboon,” said co-discoverer Steve Ward of Northeastern Ohio Universities College of Medicine and Kent State University. It weighed about 60 pounds and stood 4 to 5 feet tall with a long, flexible spine and strong grasping hands.
That creature arose during a key epoch in pre-human evolution called the Middle Miocene (about 16 million to 11 million years ago) in which the lush rain forests of Africa gradually gave way to more open plains and savannas. During this period, the animals whose lineage would eventually produce gibbons, great apes and humans first ventured down from treetops and spent a little time on the ground.
Water, Billions of Years Old, Found in Meteorite THE WASHINGTON POST -- A meteorite that whistled into a West Texas yard last year contained the first extraterrestrial water ever captured on Earth, scientists reported Thursday.
Like a cosmic message in a bottle, the microscopic bubbles of primordial water are locked inside crystals of halite, the mineral that makes up table salt, but in this case has been turned blue and purple by radiation. The crystals and their liquid cargo appear to date from the dawn of the solar system some 4.5 billion years ago.
The discovery provides scientists their first chance to study actual samples of water that may have existed in interstellar space before the sun and planets were born. It also suggests there was much more water on early asteroids than anyone suspected, the researchers said, and it could help reveal the unknown processes by which this essential ingredient of life was distributed in the early solar system.
The processes by which water was acquired by Earth and other rocky inner planets have remained largely unknown. Because water in liquid form is essential to all known forms of life, the search for the origins of life, and for life on other worlds, has centered largely around the search for water. Astrobiologists called the discovery fascinating but said its implications are not yet known.
“The importance of this discovery is that for the first time we have actual samples of (extraterrestrial) water trapped inside mineral grains, which we can have in the lab and study directly -- which is really exciting,” said Michael Zolensky, an asteroid specialist and minerologist at NASA’s Johnson Space Center, and lead author of a report on the discovery in Friday’s issue of the journal Science.
Robert Clayton, of the Enrico Fermi Institute at the University of Chicago, who was not involved in the research, wrote in an accompanying commentary: “The existence of water-soluble salt in this meteorite is astonishing” and provides “the first opportunity to study solar nebular water directly.”
Based on dating analysis led by JSC scientist Laurence Nyquist, the salt grains appear to have formed at the time the sun, planets and other bodies of the solar system were still tiny seeds coalescing out of a vast cloud, or nebula, of rotating gas and dust.