Who hasn’t long to talk to the animals like Dr. Dolittle? There’s no doubt that all animals have ways of communicating with each other, whether it’s a barking dog, a color-changing squid, or even a singing gorilla. But these animal calls are far from the in-depth conversation we’re used to having over tea. That’s because almost all animals like the ability to talk using subtle changes in their vocalizations to convey complex meanings about themselves, their actions, and their innermost thoughts.
Animal researchers have tried to teach nonhuman primates to talk. They even raised chimpanzees in human homes to expose them to speaking like human babies. But all these attempts have failed. Because of some influential studies a couple of decades ago, most scientists thought that nonhuman primates’ vocal anatomy was to blame. But, according to a paper published in Science Advances this month, their brains might be the limiting factor.
The reasons why animals can not talk
While some animals can produce sounds and vocalizations for communication, they do not possess the capacity for complex language and speech like humans. Here are several reasons why animals cannot talk like humans:
Anatomy: The anatomical structure of animals, including their vocal apparatus, differs from that of humans. Animals lack certain physical structures, such as the larynx and vocal folds, essential for producing the wide range of sounds and articulations needed for human speech.
Brain Complexity: The human brain has evolved to have specialized areas associated with language processing and production, such as Broca’s and Wernicke’s areas. Animals, while having communication abilities, do not possess the same neurological complexity and brain structures required for human-like language and speech.
Lack of Symbolic Representation: Human language is built upon a system of symbols and grammar that allows for expressing complex thoughts and concepts. While capable of vocalizations and communication, animals do not possess the same level of symbolic representation and abstract thinking required for language.
Cultural Transmission: Human language is not solely based on instinct but also cultural transmission. Language is learned and passed down through generations, allowing for the development and evolution of complex communication systems. On the other hand, animals rely more on instinct and innate vocalizations for communication.
Cognitive Abilities: Animals have varying levels of cognitive abilities and communication systems. Some species, such as primates, dolphins, and parrots, exhibit more advanced communication skills and can learn to use symbols or understand a limited set of human words. However, their communication remains distinct from human language regarding complexity, structure, and grammar.
In the 1960s and 1970s, scientists studying rhesus macaques and chimpanzees used computer programs to determine the range of sounds they could make. They concluded that these primates’ throats and mouths couldn’t produce all the sounds needed for a language like ours. It supported the idea that modern humans evolved some special vocal anatomy that paved the way for language rather than developing special brain mechanisms to coordinate advanced vocal tracts.
But these critical 1969 computer models were based on plaster casts of the vocal tracts of dead rhesus macaques. Those scientists tried to shape the monkeys’ tongues and lips to approximate what a bark would look like—then estimated the whole range of movement. It may or may not have captured the full flexibility of a live monkey.
Vocal evolution
Our linguistic skills depend partly on the intricate machinery in our chests, throats, and mouths. The muscles contract the ribcage, and the diaphragm compresses the chest cavity. They force puffs of air out of the lungs and up throughout the trachea. The rushing air passes through the voice box’s larynx, vibrating thin stretched membranes or vocal cords to produce a sound.
Using the muscles in the throat, we can change how tightly the vocal cord membranes are pulled, which changes the pitch of the sound. But that’s not talking yet because the sound then passes through mouths where it needs to run the gauntlet of tongue and lips. Then, try talking while keeping your jaw, tongue, and lips still.
So while the larynx is responsible for turning a puff of air in the lungs into a sound in the throat, the flexible part of the mouth shapes the words we say. But why’d animals fallen short? Even gorillas and chimpanzees are our closest evolutionary relatives and don’t have anything like the complex language we humans do. Scientists think that it’s down to the shape of their mouths and throats. Our impish cousins have short-sloping necks and large protruding jaws, giving them big mouths, which could be eaten but are less good for making words.
On the other hand, humans have longer necks and smaller mouths, which gives more versatility in the noises we can make. It doesn’t take much movement of jaws, tongue, and lips to form a whole range of words. So Homo sapiens is uniquely gifted with the right-shaped throat to make the noises that call words. But we could learn something from the humble bird regarding vocal acrobatics.
Vocal learners
Birds have what’s known as a syrinx in place of the larynx. They can produce some of the most beautiful and complex songs with it. Searing Cesare is even versatile enough that some birds like parrots. Lyrebirds can form human words and imitate the sounds of machinery and vehicles. What sets these extraordinarily gifted birds apart is their vocals and learners. They can hear a sound learn how to make it, and then repeat it. It’s like us mimicking the wolf of a dog or the cow.
Humans are vocal learners, and so apparent, but not many other animals are. They’re only able to make the sounds. The secret lies not in the shape of the voice box but in its connections with the brain. Vocal learners have a direct link between their forebrain and vocal muscles. It gives them precise control and understanding of the sounds they can make. But while they might be able to understand how to make the sounds.
No other animal has yet shown that it understands what those sounds represent. With one exception African Grey parrot called Alex, who, during a day of learning to repeat color words, looked at himself in the mirror and asked what color am I. To ask an existential question like that, Alex must have cracked the fundamental skill of speaking and organizing words into meaningful, novel sentences.
Aside from Alex, only humans have ever been known to do this. It’s probably a direct result of how big and complex brains are. Humans have specific brain areas dedicated to understanding, planning, and producing speech. They’re called Broca’s area, and the Verne occurs area.
Monkeys and apes have similar structures involved in making and face gestures. But that’s where the similarities end. Monkeys’ noises come not from Broca’s area but from the more primitive limbic system and brain stem. It’s a particular quirk of neurology that means we can perform mental acrobatics to grapple with language.
Gene mutation
Have you ever wondered why humans are the only species capable of talking? If chimps are so smart, why can’t they speak? Scientists have discovered the reason behind humans’ unique ability to produce and understand speech, and it turns out.
It may have arisen from a gene mutation over half a million years ago. That gene is called FoxP2 and exists in humans and chimps. Its connection to language was first discovered in family members who had severe speaking and understanding speech difficulties. That family was found to be carrying a mutated version of the gene.
A study published in Nature about FoxP2 showed that the human and chimp versions of the gene look different and function differently. Somewhere around that time, humans began developing the capacity for speech. Our FoxP2 gene became mutated. That mutation resulted in different gene targets being switched on or off in human and chimp brains.
In that study, scientists genetically engineered mice to express the human form of FoxP2. Given that mutation, mice learned to run a maze much more quickly than normal mice. It means their learning capacity was effectively enhanced. Specifically, they developed the ability to turn mindful actions into behavioral routines. It is a necessary learning process for developing language.
- It hinges on two key types of memories: declarative memory, the memory of events and places, and procedural memory needed for routine tasks.
In humans, those two types of memories work in conjunction. So when somebody shows us a hand, for example, and says the word “hand,” – we’re transforming the experience of hearing that word into an automatic association. Human brains now associate the word hand with objects that look and function like hands once we learn that association, it’s with us forever.
That’s why, when performing routine actions, like driving to work, we don’t need to think about it as we’re doing it consciously. But that’s not the case for other species. Our unique ability to do that is an essential part of how we’ve come to develop and understand speech.
It’s crazy that a single gene mutation could be responsible for our language development. It doesn’t completely rule out the possibility that other animals could someday develop speech. Of course, even if they did develop that mutation naturally, it would still take thousands.
Animal Vocal Experiment
A team of international researchers wanted to create an updated model. These researchers took X-ray videos of three living rhesus macaques while making different facial expressions: noises, chewing, and swallowing. They digitally traced the monkeys’ vocal tracts’ outlines and used those tracings rather than estimated movements.
To create a computer model of how they could contort their mouths and throats. Some fancy math let them calculate the range of sounds the monkeys could theoretically make, using an English-speaking adult human female for comparison.
The scientists concluded that the macaques should make almost most vowel sounds in American English. They even used their results to simulate what it would sound like if a macaque said, “Will you marry me?” mixed with some noise. It’s terrifying. But the creepiness is beside the point. Why did they choose that particular phrase?
But these researchers made this model fly in the face of decades of belief that nonhuman primates can’t talk. It’s because their throats can’t make the right sounds. Instead, their brains might be the limiting factor. After all, even though the physical pieces are mostly in place. Their neural circuitry doesn’t give them a fine level of control. They need to mimic human language.
So it seems that when we’re chattering over a cup of tea, we use a startlingly complex combination of physical and mental apparatus. Other animals might have that talking toolkit, but we have the complete package alone.
More Articles:
Can Humans Breed With Animals?
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How Does Evolution Process Work?
What Makes Humans Different From Other Animals?
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References:
Jordania, Joseph. Who Asked the First Question? The Origins of Human Choral Singing, Intelligence, Language and Speech. Tbilisi: Logos. ISBN 978-99940-31-81-8.
Kirby, Alex. “Parrot’s oratory stuns scientists.” BBC News.
F.X. Plooij. “Some basic traits of language in wild chimpanzees?”. In A. Lock (ed.). Action, Gesture, and Symbol. New York: Academic Press.
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