A study conducted by researchers of chimpanzees at Taï National Park in the African country of Côte d’Ivoire has found that chimps are capable of complex vocalizations and possess a dictionary of around 400 words.
According to research published in Communications Biology, the scientists discovered that “Chimpanzees produced 390 unique vocal sequences.”
“Most vocal units emitted singly were also emitted in two-unit sequences (bigrams), which in turn were embedded into three-unit sequences (trigrams),” the scientists continued.
Due to the arrangement of the vocal sequences, the scientists believe the chimps could possibly learn new words.
“From a purely structural perspective, the capacity to organize single units into structured sequences offers a versatile system potentially suitable for expansive meaning generation,” they wrote. “Further research must show to what extent these structural sequences signal predictable meanings.”
The researchers said that the evidence points to chimps clearly having very malleable vocal cords.
“What is astonishing in the chimpanzee vocal repertoire, compared to other non-human animals, is the extreme flexibility in which they can combine their limited number of signals,” said Catherine Crockford, co-author of the study, told Salon.
“This line of research will help us understand how human language may have evolved,” she continued, adding that humans are “very limited in the sounds we actually use in speech.”
“The next step is to determine if these sequences allow chimpanzees to convey substantially more messages to their group mates than single calls allow… [For instance,] if an animal has 10 call types and cannot combine them, they can send a maximum of 10 messages,” Crockford told the outlet. “If they can flexibly combine them, as we demonstrate the chimpanzees do, they have the potential to convey many more messages. Now we need to assess whether they really use that potential to convey many messages.”
“Other studies suggest that chimpanzee mainly vocalize about what they are currently doing (eating, resting, traveling, greeting, playing, grooming),” Crockford added. “I have only a few observations to suggest that they vocalize about things that have happened in the immediate past or what they want/will do in the immediate future.”