Harvard Anthropologist Says Neanderthals Had Language Skills

About 50,000 years ago, robust Neanderthals living in Europe and Israel were invaded by hordes of slightly built modern humans migrating northward from Africa. For thousands of years, the two separate cultures intermingled and, possibly, clashed.

Anthropologists are debating whether they also talked to each other. Was language developed far enough for Neanderthals to converse with modern humans--far enough to perhaps curse them for competing for food resources?

Terrence Deacon. an assistant professor of anthropology at Harvard University, thinks that it was. He maintains that the massive Neanderthals "had every bit of the intellectual and linguistic capability" that our direct ancestors did. Neanderthal speech may have been nasal and difficult to understand, "but they could have conversed with modern humans," he said.

Deacon bases this belief on the phenomenal growth of the human brain during thepast 2 million years and on what he calls "the discovery of a missing link in the story of  language evolution."

In growing from the fist-size gray matter of monkeys to the cantaloupe-size of modern folk, the brain has increased dramatically in proportion to the body. "We have a brain three times larger than would be expected for an ape our size," Deacon said.

All parts of the brain did not grow at the same rate. An area in the front of our heads, called the prefrontal cortex, expanded 200 percent faster than the rest of the gray matter, which itself increased 300 percent from ape to man.

Deacon's study of monkey and human brains has led him to the conclusion that language is controlled by the prefrontal area and by two other areas behind it--Broca's and Wemicke's areas.

He injected dyes into the brains of monkeys, then traced the neuronal connections of areas corresponding to the language centers of humans, as well as areas that produce the hoots, howls, coos, and calls of chimpanzees.

"The dyes, some of which are fluorescent, light up the circuitry of the brain and allow you to see the connections directly ," Deacon said.

Human speech is thought to be centered in and near Broca's area, a clump of brain cells in the front of the brain. Injury to Broca's area produces a loss of both speech production and comprehension of grammar.

Deacon found the equivalent of Broca's area in the brains of monkeys. Surprisingly, however, damage to that area does not interfere with the ability of monkeys to communicate by means of some two dozen calls and sounds.

Other researchers traced similar connections in human brains using electrostimulation tests and positron emnission tomography (PET) scans. In the former technique, selected brain circuits can be temporarily shut down, electrically speaking, and then researchers determine how this affects a person's speech.

PET scans reveal metabolic activity in the brain. They show that brain cells in front of Broca's area become particularly active when a person makes semantic associations, such as naming all the objects in a room.

This so-called ventral prefrontal area, Deacon found, connects to several areas: to Broca's area, to other areas where speech is produced and analyzed, and to primitive parts of the brain responsible for automatic, emotional vocalizations such as laughing and crying.

Monkeys Don't Cry

Therein lies a paradox. Monkeys don't cry, they don't laugh the way that we do, and they still communicate by sounds when their Broca's area is destroyed. How is this possible if their speech circuits are similar to ours?

Deacon believes that the answer lies in the development of the prefrontal cortex. As proportions of connections in this area increased relative to other pans of the expanding brain, the gray matter of primates became reorganized. Connections from the prefrontal area replaced those from more primitive, emotional, less-conscious brain centers.

The restructuring caused emerging humans to lose a large number of vocalizations that apes and monkeys use to communicate. The two dozen or so stereotypic sounds used to call mates, express fear, display anger, etc., were reduced to two--laughing and crying. Shrieking, hooting, and cooing gave way to consciously controlled speech, long on content, short on emotion.

This story is repeated today by every infant. Babies communicate first by laughing and crying, then by babbling, which Deacon refers to as "vocalization without emotion."

      Then come sounds like "no" and "mama" followed by more and more complex sequences of words.

Did Neanderthal children babble? Did adults sit around their caves talking about sources of food and the frail, flat-faced invaders from the south? Deacon answers this way: "I think that they spoke. And their speech was something like human language as we know it”

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He bases his answer on the theory that a Neanderthal's prefrontal cortex was not very different from that of anatomically modem humans. Their bones and muscles were more massive than ours; their jaws and teeth were larger; they had sloping foreheads and prominent brows. No matter; their gray matter was organized like ours, according to Deacon.

By his reckoning, the origin of language goes back 2 million years--back to human ancestors who made stone tools in Africa before Neanderthals appeared in Europe and Asia. Other anthropologists insist that language is a more recent development--as recent as 50,000 years old.

The latter argue that to produce human speech requires a larynx placed low in the throat and an arched or flexed skull base. Neanderthal fossils show that they possessed a high larynx and a straight skull base.

Deacon insists that language ability stems from the organization of the brain, not the position of the larynx or shape of the skull base. Humans whose larynx has been damaged or destroyed by disease or trauma retain the ability to speak with the help of mechanical devices.

“A lower larynx enhances the range of vowels," Deacon admitted. "But there are modern languages in which vowels are subordinate to consonants. Also, vowel changes are essentially neutral to word meaning, whereas consonant changes have serious consequences for intelligibility.” 

Some researchers side with Deacon for another reason: the recent discovery of a human-like hyoid bone in the 60,000-year-old skeleton of a Neanderthal found in northern Israel. (The hyoid is a small U-shaped bone from which the larynx is suspended.) These researchers contend that existence of the bone supports the idea that Neanderthals could talk in much the same way as we do today.

Deacon, however, does not consider this to be a critical factor. "Neanderthals were capable of language irrespective of the modem or primitive state of the hyoid bone," he said.

If that is true, it is difficult to imagine Neanderthals and modem humans not talking to each other during the thousands of years in which they were in contact.