The movie *Dawn of the Planet of the Apes* is a global hit, featuring the chimpanzee Caesar who possesses human intelligence and emotions, and can even speak and communicate with humans. But in reality, can chimpanzees truly speak like humans?
Modern apes, gorillas, chimpanzees, and some ancient apes belong to the family Apistoniaceae and are the closest animals to humans, possessing a certain level of intelligence. Their exceptional talent for learning sign language has long been proven, but why have scientists yet failed to train apes to speak in human language?
Scientists say that defects in the chimpanzee's body structure are the root cause of their inability to speak.
According to Didier Morin, a linguist at the University of Stendhal in Gernoble, as quoted by the French magazine *Science and Life*, chimpanzees' vocal organs differ from those of humans. They lack the same muscle structure and neural connections, resulting in very different ways of controlling vocalization. Compared to humans, chimpanzees have a higher larynx, a smaller laryngeal cavity, and a longer, flatter oral cavity due to their elongated face shape, making it difficult for them to produce most vowels and consonants. Furthermore, primates have stiffer vocal cords and cannot control their breathing while vocalizing like humans, leading to unstable vocalizations that often consist of only instinctive roars or "grunts."
Adrien Meguerticent, a primatologist at the French National Centre for Scientific Research, said that although the physical structure of primates hinders their ability to adjust the sounds they produce, "it would still be possible if they possessed cognitive and thinking abilities."
He believes that the main reason primates cannot speak is that their neurons and muscle tissue cannot allow them to control language independently of emotions. Numerous scientific studies have demonstrated that the roaring behavior of chimpanzees is primarily related to the subcortical areas that control emotions, rather than the areas in the left hemisphere that control language.
Therefore, although some scientific experiments have given glimpses of how chimpanzees seem to intentionally produce certain sounds of human language, these "close relatives" of humans will probably never be able to truly speak like humans.
