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Standing upright
There are lots of reasons why early humans started to stand upright. Reaching up for food in trees and running may be the ones you have heard of. But now scientists have shown that we could have stood erect in order to throw a harder punch. Could the natural selective forces of fighting rivals, be enough to drive the evolution of bipedalism?

Large mammalian brains
Mammals are incredibly diverse, but they all share a large brain to body size. But why did they evolve? Computer Tomography (CT) scans of the skulls of very early shrew-like mammals have revealed large olfactory brain regions. So could a greater reliance on the sense of smell be the cause?

Habitable planet
Astronomers think they have found the first definitely habitable planet outside of our solar system. It is in orbit around a red dwarf sun, and is in the Goldilocks zone, not too hot or too cold, but just right for liquid water to be present. It has the snappy name of Gliese 581 d.

Orphan stars
It seems that image we have of the galaxy being full of stars, with planets neatly in orbit around them, may need some revision. Japanese astronomers, writing in the journal Nature, say they have found evidence of what are being called rouge or orphan planets, which are drifting freely. So far they have identified 10, but say there could be more of these planets than there are stars.

Flooding the Mississippi
For people living in the direct path of flood water released from the spillways of the swollen Mississippi river in the United States, they may not be able to see the positive side of things. But for scientists, it is a chance to study how the river behaves.

Genes for cattle disease
Scientists have discovered two genes in cattle in Africa which might help in the fight against a devastating livestock parasite. 'African Animal Trypanosomiasis', is caused by the same type of bug that causes sleeping sickness in people.