Witnessing a silverback gorilla beating its massive chest is enough to strike fear into the hearts of even the strongest and bravest among us. This impressive display has been depicted in movies such as King Kong and Tarzan as an expression of aggression. However, there’s actually much more to the gorilla chest beating than a mere exhibition of anger or __1__.
For as long as scientists have been observing gorillas in the wild, there has been much speculation as to the true purpose and meaning of chest beating. Recent research suggests that it could be used as a way of preventing fights __2__ initiating them.
Scientists working on behalf of the National Geographic Society observed 25 male mountain gorillas in Rwanda for more than 3,000 hours between the years of 2014 and 2016. __3__ high-tech recording equipment, they recorded the frequencies of each chest beat, as well as the number of beats and duration of each instance. __4__ they found was that the largest animals produced sounds of lower frequency compared to other smaller gorillas. The researchers theorized that males with larger chests had proportionallylarger air sacslocated near their larynxor “voice box.”
Previous research has shown that the largest gorillas enjoy greater reproductive success and higher social ranking. And gorillas with a higher social position tend to have more access to mates. For this reason, chest beating may be a way for gorillas to __5__ their size to others, even across long distances. In essence, it acts as a quick and effective way to signal would-bechallengers that they’d better keep their distance.
1. (A) compliment (B) weakness (C) jealousy (D) hostility
2. (A) except for (B) in spite of (C) rather than (D) with regard to
3. (A) Used (B) Using (C) To use (D) Had used
4. (A) Whom (B) Which (C) Where (D) What
5. (A) convey (B) inform (C) dedicate (D) apply
