Salt causes the deterioration of historical artifacts
Scientists are fine-tuning the composition of cellulose poultices to maximize the extraction of salt from historical monuments.

The porosity of the various materials used throughout history to construct buildings and sculptures make them susceptible to salt absorption at rates which vary depending on geography, temperature, weather, and soil.

Salt carried by water and moisture are absorbed into the materials and deposited deep into the structures once the water evaporates. Over time, the salt reacts with the materials and compromises their strength and accelerates decay.

An analysis of the earliest fossil evidence of human lineage – a femur from the six million year old Orrorin tugenensis -- indicates that this species was bipedal. The functional and phylogenetic significance of these remains have been hotly debated since their discovery in 2000. To date, no one has measured and analyzed the shape of these bones and compared them to modern humans, living apes and other fossil hominins. Recently, though, researchers were granted permission to measure the original fossils in Kenya. Their results reveal and confirm bipedal adaptations. The bones closely resemble those from Australopithecus and Paranthropus, circa 3 to 2 million years ago, contradicting the hypothesis that Orrorin is more closely related to Homo than to Australopithecus.

The study, published in the journal Science, says the first Americans had their roots in southern Siberia and ventured across the Bering land bridge connecting Asia and North America about 22,000 years ago. But they probably did not migrate down into the Americas until 16,000 years ago, when an ice-free corridor in Canada opened.

Genetic evidence points to a founding population of less than 5000 individuals. Archaeological evidence, meanwhile, suggests that the so-called Clovis culture, distinguished by its unique stone tool kit and dating back about 13,000 years ago, may have been relative latecomers to the Americas.

In the late Cretaceous era, about 80 million years ago, global levels were 560 feet (170 meters) higher than today, according to a reconstruction of ocean basins from the time.

The predator represents one of the biggest species of pliosaur known to science, researchers say. Pliosaurs were the top marine predators during the dinosaur era.

Buried underneath the troubled Darfur province in northwestern Sudan is an ancient mega-lake, satellite data shows. Scientists believe there may be an abundance of groundwater still buried there.

The extraction of groundwater could help alleviate the political conflict in Darfur, some experts say, because the fighting in the region stems in part from a battle over water.

Radar waves penetrating the fine-grained sand cover in the hot and dry eastern Sahara revealed buried features of a lake as large as Lake Erie, the tenth largest lake on Earth. Farouk El Baz, director of the Center for Remote Sensing at Boston University, says up to a dozen channels of water supplied the lake more than 5,000 years ago.

The discovery may help scientists expand their knowledge of continental climate change and regional paleohydrology. The ancient lake represents evidence of the past rainy conditions that existed in the eastern Sahara.

According to the researchers, mapping the site of the former lake, named the Northern Darfur Megalake, will help with groundwater exploration efforts in the Darfur region, where access to water is essential for refugee survival.

El-Baz says the ancient lake discovered in Darfur is similar to his earlier detection of the "East Uweinat" basin in southwestern Egypt -- where the groundwater rises to 25 meters below the surface -- and which resulted in the drilling of 500 wells to irrigate 100,000 acres of agricultural land.

Tim Bromage, an adjunct professor at New York University College of Dentistry, has reconstructed a skull belonging to the species Homo rudolfensis, which was discovered in Kenya in 1972.

Bromage used a deformable cast and computer-generated models to create replicas of the skull that could be shaped.

The analysis suggests that the specimen had a smaller brain than scientists had believed as well as a distinctly protruding jaw.

But other experts expressed skepticism about Bromage's argument that the repositioning of the specimen's face means its brain size must have been smaller.

"It's probably right that the face should stick far more forward. But to say that because they've changed the angle of the face, the brain size has to get smaller doesn't make any sense," said Robert Martin, a biological anthropologist at the Field Museum in Chicago, Illinois.

"The [specimen's brain] certainly isn't as small as [Bromage is] now arguing."