Great ape language

Great ape language research historically involved attempts to teach chimpanzees, bonobos, gorillas, and orangutans to communicate using imitative human speech, sign language, physical tokens and computerized lexigrams. Scientists wanted to understand how close apes’ communication was to human language and what this might tell us about their intelligence.

These studies sparked big debates. People argued about what really counts as “language,” whether it was fair to the animals being studied, and how much we were just projecting human ideas onto them. Even though many interesting things were learned, most language experts still believe that human language is something special and unique to us.

Today, scientists have shifted their focus. Instead of trying to teach apes human language, they watch how apes talk to each other in zoos and the wild. They study gestures, facial expressions, and sounds apes make to each other, giving us new insights into how these amazing animals communicate in their own ways.

1890s: Richard L. Garner

Richard Lynch Garner was the first researcher to study how nonhuman primates communicate. He began by observing monkeys in American zoos and later traveled to Africa to watch gorillas and chimpanzees in the wild. He wrote three books about his findings: The Speech of Monkeys (1892), Gorillas & Chimpanzees (1896), and Apes and Monkeys: Their Life and Language (1900).

Garner believed that these animals had their own ways of "speaking." He even lived in a cage to better observe gorillas. Although his methods were not scientific by today's standards, his work was important because he studied the animals in their natural homes and was one of the first to record their sounds for later study.

1930s: Cross-fostering and efforts to teach speaking

Scientists tried to teach chimpanzees to speak by raising them like human children. In one study, a chimpanzee named Gua was raised alongside a human child. Gua could make different sounds to show her needs but did not learn to speak human words. Instead, the human child sometimes copied Gua's sounds.

Later, another chimpanzee named Viki was raised by a couple who tried to teach her to speak. After many years, Viki learned only a few words like mama and papa. These studies showed that while chimpanzees could understand and make some sounds, they did not learn to speak like humans.

1960s–1980s: Sign language

Washoe and the Gardners

Main article: Washoe (chimpanzee)

In 1966, researchers Beatrix T. Gardner and Robert Allen Gardner began teaching a chimpanzee named Washoe to use American Sign Language (ASL). They chose sign language because they believed Washoe might struggle to make human sounds. Washoe lived with the Gardners and learned to use signs to communicate. By the time she was three years old, Washoe could use 85 different signs, and later she learned even more.

The Gardners made sure their work was carefully tested. They used a special setup where Washoe would see pictures and then sign what she saw. This helped make sure that Washoe was really understanding and not just copying what she saw.

Washoe and Roger Fouts

Main article: Roger Fouts

Roger Fouts, one of Washoe’s caregivers, believed that teaching Washoe should be more like how human children learn. He thought that strict rewards and punishments were not the best way to teach a language. Instead, he felt that Washoe needed time and a relaxed environment to learn naturally.

Nim Chimpsky

Main article: Nim Chimpsky

In 1973, another chimpanzee named Nim Chimpsky was taught sign language by Herbert S. Terrace. Nim had many different caregivers, and his upbringing was not stable. This made it hard for Nim to learn and behave well. Terrace later said that Nim mostly copied signs to get rewards and did not truly use language.

Koko

Main article: Koko (gorilla)

In 1972, Penny Patterson began teaching a gorilla named Koko to use sign language. Koko learned about 1,000 signs. However, many scientists felt that Koko was not really using language because she did not use the rules of grammar or sentence structure.

Visual symbols

Some researchers tried to teach apes to communicate by using visual symbols, like plastic tokens or special picture boards. Psychologist David Premack worked with a chimpanzee named Sarah and used plastic tokens to help her learn simple words and follow commands. Sarah could answer questions and make requests, but she did not ask questions herself.

Another ape named Kanzi, a bonobo, learned to use a special board with symbols called a lexigram. By pressing these symbols, Kanzi could tell researchers what he wanted or where he wanted to go. Kanzi showed that he could understand and respond to complex questions, though his way of speaking was quite different from human language.

Main article: Kanzi

Criticism and controversy

In the 1970s and early 1980s, there was much debate about what really counts as "language." Some researchers taught chimpanzees and other great apes to use signs or symbols to communicate. They celebrated their success, but many experts argued that this wasn't true language because the apes didn't use sentences or grammar.

One famous study with a chimp named Nim Chimpsky showed that the apes were just learning to follow instructions, like trained animals, rather than truly using language. This led many scientists to question the earlier exciting claims about apes talking. After these debates, support for this kind of research dropped off, and some researchers turned to other projects to care for the apes they had worked with. The treatment of these apes also raised ethical concerns, with critics saying it was wrong to isolate them and train them in ways that caused them stress.

Contemporary research

Animals like monkeys and apes use body movements, faces, sounds, and smells to share feelings or warn about danger. They also groom each other to strengthen group bonds and sometimes show aggression to keep groups separate. Humans, however, mainly use spoken words to communicate.

Scientist Tetsuro Matsuzawa suggests that as humans evolved, we may have traded away some short-term memory skills for better language abilities, according to his cognitive tradeoff hypothesis. This trade helped us develop the complex talking we use today, using short-term memory and working memory in new ways.