Inbuilt storage

Earth's mantle could be holding three times the water found in oceans

 
Last Updated: Saturday 04 July 2015

earth

Earth's mantle
could turn out to be the single largest water reservoir on the planet. Deep pockets of magma have been found 600 km beneath North America in the transition zone (see diagram). Magma gets formed due to melting of rocks and water is crucial to this process. The new find indicates it is the surface water that gets pushed to such great depths due to tectonics. The water found at these depths, however, is not in liquid, ice or vapour form. Due to severe pressure and high temperature, water molecule splits to form a hydroxyl radical (OH) which gets attached to minerals in rocks. It is not known yet whether the phenomenon is uniform throughout the planet, but the discovery could give clues to the formation of Earth, volcanic eruptions, the presence of water on Earth's surface, and even alter current theories on Earth's composition. Science, June 13

BIOLOGY
Eucalyptus genome decoded
THEGENOME
of eucalyptus, the most widely planted hardwood tree in the world, has been sequenced. The tree has innumerable uses, from medicinal to that in construction, and is also a potential biofuel. Decoding genome sequence is essential to understand the growth qualities of the tree which allow it to thrive in over 100 countries. The properties can then be added to other biofuel species. Genes responsible for the production of cellulose and the hemicellulose xylan (carbohydrates used as biofuels) in eucalyptus have also been identified. Nature, June 11 (carbohydrates used as biofuels) in eucalyptus have also been identified. Nature, June 11
 
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Beaten into shape

FISTFIGHTS
have left a lasting impact on the human face, literally. Shape of the human face, especially of australopiths, evolved into its present form to minimize injury from punches. This new theory is in contrast to the long-held hypothesis which said the face evolved to chew hard food. The bones which face the maximum damage in fist fights are the ones which have seen the maximum increase in strength in the evolutionary course. The theory gives clues not only to the evolution of musculoskeletal features, but also indicates that our distant past was highly violent.
Biological Reviews, June 9
ENVIRONMENT
New ozone depletors found
TWONEW chlorofluorocarbons (CFCs) and one new hydrochlorofluorocarbon have been found in the atmosphere, taking the total number of CFCs to seven. The discovery was made by comparing samples of present day air to those collected between 1978 and 2012 in Tasmania, Australia. CFCs damage the ozone layer and the discovery indicates that there may be other such gases present which remain unidentified. Atmosphere, June 4

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