In this blog post, we will look at various perspectives on whether human language ability is an evolutionary adaptation by natural selection or a byproduct of the brain.
We use speech and writing to convey our thoughts to others. Language is the most important tool for conveying human knowledge and emotions, and it forms the basis of culture. It enables people to communicate on a daily basis, as well as to engage in philosophical reasoning, historical records, and artistic expression. Therefore, language skills have become an essential element that affects all aspects of human society. When we use language, we use our language skills to construct sentences and use appropriate vocabulary and grammar to create meaningful words and writing.
Where did these language skills come from? Did our language skills arise as a result of adaptation in the process of human evolution? The adaptation we are talking about here is not simply a change in behavior or learning that occurs in an individual’s lifetime. According to evolutionary biologists, adaptation refers to the phenomenon in which a specific mutation in an individual becomes established as a result of natural selection over generations. This adaptation results in the modification of genes and bodies to suit the external environment, and plays an important role in the survival and prosperity of the group.
Among evolutionary biologists, there has long been a debate over whether language ability is a product of adaptation. Scholars who believe in the powerful force of natural selection explain it from an “adaptationalist” perspective, while those who are skeptical of it discuss it from a “counter-adaptationalist” perspective. The two sides have held opposing positions on this topic, and books such as “Darwin’s Table” vividly illustrate the details of this debate. Adaptationists argue that language skills have become an essential tool for human survival and have therefore evolved through natural selection. On the other hand, anti-adaptationists maintain that language is merely a byproduct of advanced cognitive abilities and cannot be seen as an adaptation.
I do not agree with the extreme adaptationist view that everything in the phenomenon of life is the result of evolutionary adaptation, but I do think that natural selection has played a significant role in language ability. Human language ability acts as a unique survival mechanism and has greatly contributed to the adaptation of humanity to the environment by enabling the transmission of information and cooperation within the group. For example, primitive humans had to develop verbal communication as a prerequisite for understanding each other’s intentions, cooperating, avoiding danger, and achieving common goals. This process of developing language skills can be seen as an essential adaptation for survival, rather than just a byproduct of the brain.
To gain a deeper understanding of the debate between the adaptivists and the anti-adaptivists regarding language ability, it is interesting to look at the arguments of both sides in detail. Adaptivists believe that language has developed for the purpose of communication with others, not for simple monologues. They argue that language has contributed to human survival and reproduction, citing how important communication was in various primitive societies. In contrast, the anti-adaptiveists see human language as a byproduct of complex cognitive abilities that have arisen naturally. They argue that language skills only appeared as a side effect of the highly developed human brain, and that it is an overinterpretation to see this as an adaptation.
Human body structure is an important clue that shows that language skills are an adaptation. For example, the human vocal organs, especially the vocal tract, are so elaborately constructed that they enable us to produce a wide variety of sounds. The vocal tract consists of the glottis, pharynx, oral cavity, nasal cavity, and lips, each of which performs a specific function to produce sound. This physical structure suggests that language is not a simple incidental function, but the result of intentional and functional evolution. Just as with the eyes, we receive visual information through our eyes, but we do not see the eyes as simply a byproduct of the brain. Just as the eyes have developed into specialized organs to obtain visual information that is important for survival, the vocal organs have also evolved for communication, so language ability is more than just a byproduct of the brain.
In addition, there are studies that show that language ability and cognitive development can be separated. When we look at the process of children acquiring language, language acquisition ability develops rapidly mainly in the early stages of life and gradually decreases thereafter. On the other hand, cognitive ability develops over a longer period of time, increasing until the age of 20 and then decreasing. This difference in developmental curves suggests that language ability and cognitive development have independent pathways. Cases of specific language disorder and Williams syndrome provide further evidence for this. People with Williams syndrome show excellent language skills despite their low IQ and cognitive difficulties, which is a good example of how language and cognition can develop separately.
Furthermore, language-related genes such as the FOXP2 gene are also important evidence for the evolution of human language skills. FOXP2 is present in all mammals, but in humans, a specific mutation occurs that enables the ability to speak complex languages. Surprisingly, this gene mutation was found to have appeared at the same time as the emergence of Homo sapiens, suggesting that language skills were established through natural selection. These gene mutations had a positive impact on survival and reproduction, spreading rapidly and becoming the basis for the language skills that are now common to all humans.
Ultimately, it is important to distinguish between language and language skills when discussing the fact that language skills are an adaptation that emerged during the evolutionary process. Language is a means and a tool for communication between people, and it is a kind of system that emerged when communication was needed. On the other hand, language ability is a unique ability of humans to acquire, express, and understand language, based on the biological and neurological foundations that make it possible. Therefore, it should not be overlooked that language is an adaptation that has become the result of natural selection, rather than simply a cognitive byproduct.
Therefore, language ability can be understood as a unique adaptation of humans that evolved through natural selection. Early humans sought cooperation and survival through communication, and language ability played an essential role in this process. The evolution of the vocal organs, the FOXP2 gene, and the differences in language acquisition and cognitive development are all strong evidence to support this. The questions raised by the anti-adaptivists have provided an important opportunity to develop academic debate by cautioning against extreme interpretations of adaptivism, but their claim that language ability is not a result of adaptation is just a plausible hypothesis that fails to fully consider the evolutionary importance of language ability.
