Another 1994 study by the same researchers found that humans were still able to identify an infant's cries, even when the sound was altered by recording it from a distance outdoors.
But pretty good isn't perfect. University of Florida researcher Harry Hollien, in his 2001 textbook "Forensic Voice Identification," notes that in a 1970s study, he found examples of babies whose voices were hard to tell apart.
"When two babies sounded similar, their mothers not only correctly identified their own child, but also identified the other one as theirs," he writes.
And recognizing the voice of an adolescent or adult in a stressful situation is a trickier task.
Hirotaka Nakasone, an FBI voice analysis expert, testified for the prosecution that an extreme emotional state can significantly alter a person's pitch, increasing the vibration of the vocal cords from 120 to 220 hertz to 500, 600 or even 700 hertz.
Additionally, a person's resonance -- the ability to project, a key part of what makes one person's voice sound distinctive -- can also be affected, he testified. Nakasone testified that it was beyond the ability of present scientific methods to identify the voice.