9 . Young babies make many short and word-like sounds such as “ba” or “aga”. Those early sounds are later replaced with words and, eventually, sentences. While some of them are born to be more talkative than others, a new study confirms that male babies make more sounds than female babies in the first year.
While the research confirms earlier findings from a much smaller study by the same team, they still come as a surprise. That’s because there’s a common and long-held belief that females have an advantage over males in language.
In the study, Dr Kim and his team included more than 450,000 hours of all-day recordings of 5,899 babies, using a device about the size of an iPod. Those recordings were processed to count the number of words spoken by babies and adults across the first two years of life.
Generally, the data showed that male babies made 10% more sounds in the first year compared to females. In the second year, the difference turned directions, with female babies making about 7% more sounds than males. Those differences were observed even though the number of words spoken by adults caring for those babies was higher for female babies in both years compared to males.
Why, then, would male babies be more talkative than females in the first year and not later? “We think it may be because boys are more likely to die in the first year than girls. Given that so many male deaths happen in the first year, boys may have been under especially high selection pressure to produce fitness signals to express their wellness and improve their chances of surviving,” says Kim. By the second year of life, as death rates drop sharply across the board, he added, “the pressure on special fitness signaling is lower for both boys and girls.”
1. Why are the findings of the new study surprising?
| A．They are similar to earlier ones. |
| B．They show males are more talkative. |
| C．They go against people’s common belief. |
| D．They show babies learn language differently |
2. What did the study find about male babies in the second year?
| A．They received more language input. |
| B．They showed better language abilities. |
| C．They communicated more with adults. |
| D．They made less sounds than female babies. |
3. What might cause the change in sound production for male babies?
| A．Improved language skills. | B．Change in living environment. |
| C．Less need for fitness signaling. | D．Increase in social communication. |
