According to a recent study led by the University of Warwick, orangutans are able to produce two separate sounds simultaneously. This ability is much like songbirds or human beatboxers.
These findings could shed new light on the evolution of human speech. They may also help us understand the interesting rhythms of human beatboxing.
The experts observed two populations of vocalizing orangutans in Borneo and Sumatra for a total of over 3,800 hours. From this, they discovered that primates from both groups were capable of producing highly complex types of vocalizations.
“Humans use the lips, tongue, and jaw to make the unvoiced sounds of consonants, while activating the vocal folds in the larynx with exhaled air to make the voiced, open sounds of vowels. Orangutans are also capable of producing both types of sounds – and both at once,” explained study lead author Adriano Lameira, an associate professor of Psychology at Warwick.
“For example, large male orangutans in Borneo will produce noises known as “chomps” in combination with “grumbles” in combative situations. Female orangutans in Sumatra produce “kiss squeaks” at the same time as “rolling calls” to alert others of a possible predator threat. The fact that two separate populations of orangutans were observed making two calls simultaneously, is proof that this is a biological phenomenon.”
According to the scientists, humans rarely produce both voiced and voiceless sounds simultaneously. One exception is beatboxing. This is a form of vocal percussion in which individuals imitate drum sounds and create rhythmic patterns using their voice, mouth, lips, and throat in order to imitate the complex beats of hip hop music.
The fact that humans are anatomically able to beatbox raises the question about where this fascinating capacity came from. The current study suggests that it may have evolved from vocal abilities already existent in our primate ancestors.
Unfortunately, previous research focused on the vocal abilities of birds has largely underestimated the amazing vocal control and coordination abilities of wild great apes and thus failed to identify the possible evolutionary link between primate vocalizations and the emergence of human speech and other complex vocal capacities such as beatboxing.
“Producing two sounds, exactly how birds produce song, resembles spoken language but bird anatomy has no similarity to our own so it is difficult to make links between birdsong, and spoken human language,” said co-author and independent researcher Madeleine Hardus.
“Now that we know this vocal ability is part of the great ape repertoire, we can’t ignore the evolutionary links. It could be possible that early human language resembled something that sounded more like beatboxing, before evolution organized language into the consonant – vowel structure that we know today,” Lameira concluded.
The study is published in the journal PNAS Nexus.
Orangutans are known to have a complex set of vocalizations, with several distinctive calls and sounds. They use these vocalizations to communicate with each other in various scenarios, such as alerting others to danger, indicating their presence, or expressing emotions such as frustration or fear. Here are some of the known orangutan vocalizations:
Adult male orangutans are famous for their “long call.” It’s a series of roars that can last up to two minutes and be heard as far as one kilometer away. The long call has many purposes, including attracting females, communicating with other males, and signaling their location.
Orangutans make a “kiss squeak” noise by pursing their lips and sucking in air. This is often a sign that an orangutan is annoyed or feels threatened. Some orangutans will even use leaves to make this sound louder, suggesting that it is a deliberate form of communication.
Orangutans produce a grumbling sound, typically used for close-range communication, such as between a mother and her offspring. It’s a general sound to express dissatisfaction or mild protest.
Young orangutans often emit soft hoots or squeals when they are playing, excited, or exploring. These vocalizations can also be used to gain the attention of the mother or other young orangutans.
Throat scrapes and rasps are low, quiet vocalizations used for close-range communication and often occur during social interactions.
Remember, these vocalizations can vary between different populations of orangutans, as these great apes are known to have culturally distinct behaviors. This means that different groups of orangutans, living in different geographical areas, may have their own unique sets of calls and responses.
Video Credit: Adriano R. Lameira and Madeleine Hardus