lIn infancy, normal children
 sing, babble, produce undulating
 patterns, and imitate tones sung by others.  
 lAn important transition in their musical lives occurs in
 the middle of the second
 year of life when them begin to emit tones that explore small intervals from seconds to fourths.  
 lThey begin to invent spontaneous songs and imitate short patterns from familiar songs.  
 lBy age three or four, the
 original tunes and exploratory sound
 play give way to conformity as they begin to limit themselves to the songs of the dominant
 culture.  
 lBy school age, children know what a song should be according to the cultural practice.  They can
 produce a fairly accurate
 rendition of common melodies.