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Fossils Put First Prehumans In Europe Earlier
A new branch may be budding on the human family tree. Hominid fossils at least 780,000 years old have been discovered in caves near Burgos, Spain. The fossils, which include the remains of an adolescent and a child, do not readily match those of known species of human precursors, reports Eudald Carbonell of the University of Tarragona, who leads a team of researchers at the site. His team's discovery appears in today's issue of the journal Science.
If the dating of fossils and implements from the site holds up, Europe's first human-like inhabitants must have arrived 500,000 to 1 million years earlier than previously thought. Thus the discovery could fill a gap in anthropologists' understanding of how prehumans migrated from Africa to Europe, the Middle East, and Asia.
Aerosols improve climate modeling
Coal, oil, and gas have been identified as the terrible trio in global-warming scenarios. When burned, these fossil fuels give off the greenhouse gas carbon dioxide as a byproduct. In one of the many ironies in science, this release of CO2 also carries with it the seeds for moderating the greenhouse effect. Four researchers from the Hadley Centre for Climate Prediction and Research in Britain report in yesterday's edition of the journal Nature that when sulfate particles (aerosols) - another byproduct of fossil-fuel combustion - are added to their computer climate-change model, its ability to mimic past climate patterns greatly improves.
The aerosols offset the greenhouse effect by reflecting solar radiation back into space. Thus, the Hadley researchers' model helps explain why global temperatures derived from previous models generally have been higher than those recorded. To Tom Wigley of the National Center for Atmospheric Research in Boulder, Colo., the significance of the work at Hadley is the improvement in climate modeling's accuracy.
Galaxies in the making?
Nobody said the Hubble Space Telescope would make life easier for astronomers. Analyzing Hubble images of 28 distant, energetic galaxies, and comparing them with data on the same galaxies from infrared and radiotelescopes, researchers from Britain and the Netherlands released preliminary data this week indicating that these galaxies are much more complex than astronomers originally thought.
Many believe that massive black holes at the galaxies' centers spawn the bizarre features these galaxies display, such as powerful jets of gas extending far beyond the galaxies themselves. Images from ground-based telescopes have shown that the galaxies are elongated along the direction the jets project. The three researchers from the Cavendish Laboratory at Cambridge University and from the Leiden Observatory in the Netherlands noted that these elongated portions, which look fairly uniform in ground-based images, contain hot clumps of gas - perhaps the breeding ground for new stars. In some galaxies, these clumps lie along the jets' axis; in others, they merely cluster around the galaxy. These differences, they suggest, could represent galaxies in different stages of evolution.