Buzz
Though babies can't talk, by just a few months old, they've already established many vocal traits that will later define their speaking voice. This conclusion comes from a study featured in The New York Times, where bioacoustic researchers discovered that analyzing an infant's cries can reveal what their voice will sound like at age 5.
In their research, published in the journal Biology Letters [PDF], the scientists recorded the voices of 15 French children, aged 4 to 5 years. They compared these recordings with the children's 'mild discomfort cries' taken when they were between 2 and 5 months old. The findings revealed that a baby’s cry can predict 41 percent of the vocal pitch variation they will have at age 5.
Other research has indicated that the characteristics of our voices in childhood are strong indicators of their sound in later years, even after puberty alters our vocal cords. For example, a boy's voice pitch at age 7 can forecast up to 64 percent of the unique features his voice will retain as an adult.
The authors of the study suggest that many of these differences may develop even before childhood, potentially while still in the womb: "These observations suggest that inter-individual differences in [voice pitch] arise early in life and are largely unaffected by puberty, and raise the possibility that [pitch] may even be determined before birth."
The primary factors that influence pitch are the length, size, and tension of our vocal cords. However, these aren't the only determinants: Environmental elements such as smoking, pollution, and climate can also impact how our voices sound, though these changes tend to be short-lived.
