New Study: Orangutans Challenge Decades of Mathematics and Provide Insight Into Origins of Language Itself

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Written by Austin S.

Published: October 2, 2021

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For decades researchers have been studying orangutans’ language and linguistic patterns in order to seek answers for human speech development. Due to their complex sound arrangements and also the use of consonant and vowel-like sounds, orangutans may be our closest relative language-wise.

Researchers use orangutans to study our own language development because they were the first species to evolve beyond the “great ape lineage”. Orangutans are also the only ape-like species to use consonants and vowels in their communication and have one of the more complex and developed language systems in the animal kingdom.

In a study out of the United Kingdom, researchers have uncovered new information about how orangutans communicate. This information is changing what we know, what we have already accepted about human speech development, and throws into question the current mathematical formulas we use to study our language.

The Study

In their study, researchers asked what would happen to the meaning of orangutans’ language when traveling over a large space. For example, when humans shout across a field at their friend. In human language, space muddles our language’s meaning. We may be able to recognize our friends’ voices, but not understand what they are saying.

Researchers played recorded orangutan sounds across the rainforest at 25, 50, 75 and 100 meters. They discovered that though the distance continued to increase and the quality of the message stayed the same. They continued to test the sound and found that the message remained clear until the sounds were inaudible.

For this test, the researchers used recorded orangutan sounds from previous studies in Indonesia. They selected sounds that had clear consonants and vowels in the language.  The purpose of the study was to look at the sounds alone as a “packet of information”. They hoped to eliminate other language identifiers such as facial expressions, gestures, and other body language by transmitting the sounds over a distance.

They expected these sounds to function like human language – the meaning would become more muddled as the distance increased. They did not expect the meaning to remain clear as the distance increased.

Despite previous research indicating that language should become muddled across a distance, this study shows that we still have lots to learn about linguistic evolution.

Results and Impact

The clarity of the orangutan’s calls throws into question the mathematical formula researchers have used for 20 years to study humans’ linguistic development. This formula assumes that language has a limit on how far it can travel before losing its meaning. In the original research conducted by Harvard scientists, studies assumed that early humans would link sounds together in order to make language travel over a distance.

Learning that orangutan calls don’t lose meaning over great distances, but rather just distort the sound is causing linguistic researchers and evolutionary psychologists to question the ways they believed human communication developed. Though the mathematical formulas suggest a linear language process, this study indicates that we are just at the beginning of understanding our linguistic roots.

In the future, researchers hope to begin deciphering the meaning of orangutan calls. Studying the building blocks of this species’ language development will hopefully shed more light on our own language evolution. Evolutionary psychologists and linguistic researchers are hoping that this study will lead to more studies that apply mathematical models to real life data.

By continuing to study orangutan calls, their meaning, and their evolution, we will hopefully find the key to our own linguistic history.

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About the Author

Growing up in rural New England on a small scale farm gave me a lifelong passion for animals. I love learning about new wild animal species, habitats, animal evolutions, dogs, cats, and more. I've always been surrounded by pets and believe the best dog and best cat products are important to keeping our animals happy and healthy. It's my mission to help you learn more about wild animals, and how to care for your pets better with carefully reviewed products.

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