Published: Thursday 30 June 2005

family tree: An interesting project using genetics to trace how humans colonised the earth was launched recently. Called the Genographic Project, it proposes to collect DNA from hundreds of thousands of people worldwide, including indigenous people, over the next five years.

By analysing the DNA, researchers working on the project hope to track down past migrations and develop a family tree for humankind. Data from the project will be accessible to other scientists and used to establish a virtual museum of human history.

plant hormone:
Scientists have finally discovered how the plant hormone auxin acts. Indiana University Bloomington biologists Mark Estelle, Nihal Dharmasiri and Sunethra Dharmasiri have found the hormone helps a protein, called TIR1, to influence how and when plant cells grow and divide. Estelle said the finding is important for basic plant science, but may also lead to new insight into how related proteins function in animals, including humans.

The hormone was discovered in 1885 and has been in use since the 1930s. It causes dramatic effects on plant growth and development.

primitive hydrogen: The Earth's atmosphere in primitive times was far richer in hydrogen than used to be previously believed and could have been the source of molecules that led to the earliest life forms, according to a team of scientists headed by Feng Tian of the University of Colorado in Boulder, USA.

The study lends credence to the long-standing notion that lightning in early Earth's atmosphere helped form the molecules from which life evolved.

mobile risk: Using a mobile phone in rural areas seems to pose a greater risk of developing brain tumours than it does in urban areas, suggests a Swedish study. The finding was based on a sample of more than 1,400 adults between the ages of 20 and 80 years.

For malignant brain tumours, the risk was eight times as high for those living in a rural area as compared to those in cities, but the numbers were themselves small, caution the authors. They point out that base stations tend to be much further apart in rural areas, requiring a higher signal intensity.

Subscribe to Daily Newsletter :

Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.