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The planet earth is 4.5 billion years old and has undergone many geologial and climatic changes. Geologists know: Earth history demonstrates continuous dynamic evolution. The above figure shows climate change over the last 65 million years. The data has been gained from oxygen isotope measurements (δ18O) on benthic foraminifera by Zachos et al. (2001) and reflect a combination of local temperature changes in their environment and changes in the isotopic composition of sea water associated with the growth and retreat of continental ice sheets. Figure and citation from wikipedia.com.Ancient climate records provide clear evidence of abrupt episodes of greenhouse warming in the past. Understanding cause and effect for these events continues to remain a major challenge. For the best-documented example, a burst of warming some 55 million year ago termed the Palaeocene–Eocene thermal maximum (PETM), known increases in greenhouse gases fail to explain even half of the observed warming. Read more..nature.com
Haiti earthquake occurred in complex, active seismic region. The magnitude 7.0 earthquake that triggered disastrous destruction and mounting death tolls in Haiti this week occurred in a highly complex tangle of tectonic faults near the intersection of the Caribbean and North American crustal plates, according to a quake expert at the Woods Hole Oceanographic Institution (WHOI) who has studied faults in the region and throughout the world.....read more...sciencedaily.com
Microorganisms cited as missing factor in climate change equation
Those seeking to understand and predict climate change can now use an additional tool to calculate carbon dioxide exchanges on land, according to a scientific journal article publishing this week.
The research, publishing in the Proceedings of the National Academy of Sciences, incorporates into global computer models the significant impact an enzyme, carbonic anhydrase, has on the chemical form of carbon dioxide released from the soil and reduces uncertainties in estimates of CO2 taken up and released in terrestrial ecosystems.
The same enzyme is present in foliage and soils, but leaves a different imprint on CO2 involved in photosynthesis and respired by soils.
"Our paper presents measurements from all the major regions of the world where we have experimentally determined the effect of this enzyme, produced by many microorganisms, on carbon dioxide released from the soil," said Dr. Behzad Mortazavi, an assistant professor of biological sciences at The University of Alabama, and a co-author of the article.
from sciencedaily.com
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A research team headed by Tim White discovered in 1992 the first Ardipithecus ramidus fossils from the Afar Depression in the Middle Awash river valley of Ethiopia. More fragments, including mainly teeth, were recovered in the following years allowing the composition of 45 percent of the total skeleton.
The lines that evolved into modern humans and living apes probably shared an ancestor 6 million to 7 million years ago, in the Late Miocene. The fossils were dated as 4.4 million years of age based on its interval between the volcanic strata of the Gaala Tuff Complex and the Daam Aatu Basaltic Tuff. Studies under way indicate the species lived in the woodlands and could climb on all fours along tree branches, but the development of their arms and legs indicates they didn’t spend much time in the trees. And they could walk upright, on two legs, when on the ground. In its 2 October 2009 issue, Science presents 11 papers, authored by a diverse international team, describing the early hominid species, Ardipithecus ramidus, and its environment. 
These 4.4 million year old hominid fossils sit within a critical early part of human evolution, and cast new and sometimes surprising light on the evolution of human limbs and locomotion, the habitats occupied by early hominids, and the nature of our last common ancestor with chimps.
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