Researchers in Japan found that birds that come from the earlier eggs in a brood are more likely to be better singers. Hardiest males, who use song to show their fitness to potential mates, tend to sing the longest and loudest.  This new study found that the order in which eggs were laid was important in determining how complex a hatchling's song would be when it matured. 

It's not clear where in the order Roger McGuinn fell when he was born.