Bangalore: A chimpanzee’s grunt almost always means food, a ‘hoo’ is certainly a retort to a threat, and grunts are mostly polite greetings. And according to a new study, chimpanzees can string these sounds together in different combinations to produce “sentences” that convey different meanings.
These are the findings of an international group of researchers who observed adult chimpanzees in Tao National Park in Ivory Coast, Africa. To understand the semantic structures they use when communicating with each other.
According to the study, researchers in France, Germany and Ivory Coast found that primates could combine 12 primary sounds to form 390 “words,” or unique sequences, that could lead to language precursors.
The study was conducted in two parts in January-February 2019 and between December 2019 and March 2020 test resultwhich have been peer-reviewed, published Monday in the open-access journal communication biology,
The researchers studied 4,862 vocalizations made by 46 wild adult chimpanzees over the course of 900 hours of recordings. The study said the 12 primary sounds they identified included grunts and howls, which chimpanzees combine into groups to form phrases of different meanings.
Combinations included bigrams and trigrams – while bigrams are a sequence of two primary sounds, trigrams are recombinations of single-unit sounds and bigrams.
Chimpanzees are considered one of the more cognitively evolved species on the planet. In February, another study published in the peer-reviewed scientific journal current biology showed that chimpanzees sometimes use insects for their wounds as well as for the behavior of their friends, which may be be a sign of charity in species.
The authors of the latest study suggest that the rules they observed using chimpanzees during singing have structural complexity capable of generating new meanings by recombination of sounds, and emphasize that different sequences of vowels Further research is needed to understand the meaning of
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Bigram and Trigram
In their study, the authors classified the sounds made by chimpanzees into 12 basic units – grunt, hoo, bark, scream, whisper, pant, pant grunt, painted whoo, panted bark, panted scream, panted roar, and non-vocal. Sounds such as blowing a raspberry or the smell of lips.
Sounds with and without panting were used in different contexts – for example, single grunts were used when eating, while painted grunts were emitted during polite greetings, a ‘hoo’ emitted towards danger Whereas ‘Hus’ was painted. Used to interact with other chimpanzees.
According to the researchers, chimpanzees can combine two of these 12 main sounds to form bigrams. Some sounds tended to occur before or after others, while some beagrams occurred much more frequently than others. These bigrams were combined with other sounds to trigger or combine three unique units of sound. For example, a trigram sequence might consist of a ‘painted whoo’, followed by a grunt-bark bigram, followed by a non-painted ‘hoo’.
The authors set about analyzing three aspects of vocal communication – flexibility, or if different sounds can be combined with other sounds; ordering, or if sounds can be produced in different sequences to change meaning or context; and recombination, or whether groups of sounds combined can further recombine to form longer sequences.
Findings show strong evidence regarding the use of structurally complex syntactic vowels, with the ability to convey new meanings, According to the authors.
The ability to sequence vocalizations exists in 31 “non-human primate species,” although longer sequences are formed in communication by great apes, namely gorillas, chimpanzees, bonobos and orangutans, the authors further write in their study.
chimpanzee intelligence
The intelligence of chimpanzees has been the subject of research for many decades. For example, Washo, the female chimpanzee, was the first non-human To learn to communicate using American Sign Language (ASL), and Nim Chimpsky, who was born in the 1970s, was subjected to An experiment at Columbia University to find out is language innate,
The world’s foremost authority on chimpanzees is British primatologist Jane Goodall, who has studied the animals for more than six decades. in the beginning criticized being too humanTheir work has shown that chimpanzees have a behavior similar to that of humans. Goodall widely documented A four-year “war” between chimpanzee communities in Tanzania in the 1970s.
However, the extent of primate intelligence is as yet undetermined, as is the extent of their communication ability.
According to the authors of the new study, while chimpanzee sounds may be a precursor to language, more research is needed to determine what chimpanzee sounds mean and how well they are able to expand their vocabulary.
(Edited by Gitanjali Das)
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