Birds stammer, too
Some birds stutter just like people. Sometimes they repeat syllables, alter them or insert new ones into songs they have learnt until finally breaking out into the rest of the song. David Rosenfield of Baylor College of Medicine in Houston, Texas and his colleagues Nagalapura Viswanath and Santosh Helekar recorded the songs of 76 male zebra finches housed in their lab. Digital analysis revealed that seven per cent of them stuttered regularly. Although stuttering is thought to have a genetic component, all the stuttering birds had fluent parents. "We're unbelievably excited by this,' says Rosenfield ( New Scientist , Vol 164, No 2209).