A TEAM of stem cell researchers have done the seemingly impossible and successfully combined artificial human cells with the embryo of a chicken in a shock new experiment aimed at trying to better understand developing life. ================================================================================== Until now, scientists have been unable to answer how certain cells in a developing embryo decide to become muscles or limbs, while others become bones and nerves. But now researchers led by Dr Ali Brivanlou, from Rockefeller University in New York, have achieved the unimaginable in a shock experiment. By grafting petri dish-grown human cells onto the embryo of a chicken the scientists...