Are copper bands copper bottomed? Do you weigh less in the day than you do at night? Plus our old favourite String theory. Just some of the conundrums for Dr Karl this week. Dotun is ringmaster as Rhod is away.

In this special edition Dr Chris visits Lee Berger, at the University of Witwatersrand in Johannesburg to see the fossils which could revolutionise our understanding of the evolution of our species.

Dr Chris and his team discuss the virtues of yoghurt on the brain. Flat lenses and ice cold bacteria are also on the agenda.

The benefits of biting your nails, supernovas and what happens when an atom bomb detonantes are all put under the scientific spotlight of Dr Karl and Dr Rhod.

Dr Karl and Dr Rhod tackle why rocket thrusters work on the moon, what makes night fall, why rain doesn't hurt us and what causes tinnitus.

This week Dr Chrs and the naked scientists go to the University of Aberdeen to meet a scientist who's exploring the depths of the ocean and a look at Thalidomide 50 years on.

Dr Karl joins Rhod and as always tackles all your science questions.

Chris takes a look at work being done in Italy that may create a new treatment for muscular dystrophy

Dr Karl answers all your science related questions.

which is warmer, a bath with bubbles in it or one without? Just one of the stranger science stories tackled this week by Dr Chris Smith and the Naked Scientists!