Since the advent of comparative psychology, scientists have
tried to avoid anthropomorphising, or humanizing, their animal subjects.
Attributing human characteristics to animals is easy to do; most pet owners
will say that their pets understand at least some human language, for example.
When Dr. Duane Rumbaugh and his team began their work with nonhuman primates
and language, they began with no assumptions—not even that the apes could acquire language. They were
determined to gather evidence based on solid research methods on what
dimensions of language an ape might learn and the conditions under which they
had been learned. Given the ape’s relatively
small brain (compared to ours), the researchers’ optimism was not high.
The Beginning: Lana
Although his career did not all begin with Lana, Dr.
Rumbaugh describes her as "the grandmother of all my professional life” (2013).
Lana is a chimpanzee who learned the word-symbols and grammar of Yerkish, a
language that Dr. Rumbaugh and his colleagues created at the Yerkes Regional
Primate Center. The language consisted
of symbols, called lexigrams, on a computerized keyboard. Each lexigram
represented a word, and to ensure that Lana understood the meanings of the
lexigrams rather than simply memorizing their locations, they were moved around
on the keyboard. Lana’s achievements
still inspire researchers. In fact, Lana still participates in research.
A chimpanzee that could communicate with humans made
headlines in 1975. Unfortunately, those headlines focused on the wrong thing.
"The emphasis on Yerkish was predictable,” says Dr. Rumbaugh. "We just didn’t
predict it. They [reporters] made it seem as if we created a language that made
us magically able to communicate with the apes. The lexigrams were important
because they had to be discernable and had to fit on the keys, but at the same
time they were but tools for our research. The more important part of the whole
thing was the question ‘Can an ape really learn what the symbols mean?’”
The answer to that question is the result of some creative
genius on the part of the researchers. Dr. Rumbaugh first linked sets of the
lexigrams together, so that if any one symbol in a set was pressed, the entire
set would activate. For example, if any of the keys in the set that represented
asking for milk were pressed, Lana would be given milk. Eventually, the keys
were separated, so that Lana would have to search for and press each lexigram
in the request in order to receive milk.
Even now, more than 30 years later, Lana’s accomplishments
seem utterly fantastic. As the Yerkes Center director at the time pointed out,
"There’s just something mystical about apes, language, and computers.” Lana
learned to clearly communicate her wants, needs, and preferences using the
keyboard. More than that, she applied
what she learned in unexpected ways—to make requests that researchers never
taught her and thereby solve novel problem that she faced.
The idea that complex learning occurs through a series of
amalgams rather than by responses to individual stimuli permeates Dr.
Rumbaugh’s work. He strongly opposes the ideas that animals are simply empty
beings with no psyche, or capability to feel emotion, perceive pain, or
otherwise experience the world as humans do. Careful, varied research over the
course of his career has shown "all of the different kinds of responses are
important to gel into a larger picture. Apes are surprisingly competent at
doing that—much more than we thought 50 years ago. Animals were thought to be
unintelligent and empty, but the brain is hungry for stimulation, for
experiences of the live-a-day world as information within which it searches for
forms patterns and systems of "knowing”. That is what the brain does, day and
Dr. Rumbaugh described the way that many separate concepts
can come together and create a whole with a story that most psychology students
can relate to: "When I was in school, we called statistics class the Mystery
Hour. We all understood the numerals and some of the theories, but we still
couldn’t quite see our way through the fog. But we each eventually had an
‘aha!’ moment. The whole thing just congealed—and it was like a symphony, with
all of the parts working together.” Dr. Rumbaugh’s work has shown that apes
possess the ability to use seemingly disparate bits of knowledge to find
systems and patterns in much the same manner as statistics students.
In 2007, Dr. Rumbaugh and several colleagues published A Salience Theory of Learning and
Behavior—With Perspectives on Neurobiology and Cognition (Rumbaugh, King,
Beran, Washburn & Gould, 2007). In it, they outlined a new theory of
learning and behavior. Salience theory takes into account instinct,
conditioning, and unforeseen, novel behaviors that Dr. Rumbaugh calls emergents. "My 60 years of work led me
to a redefinition of how learning occurs. Reinforcement is not sufficient on
its own to explain learning,” Dr. Rumbaugh says. Salience theory "has been
warmly received by all but those who adhere to the ancient definition of
reinforcement. Reinforcement is reformulated in terms of attributes that all
stimuli have in a given stimulation. As we
eat or meal or an animal learns to press a key to get food, a host of stimuli
are present and are in interaction with one another. The stimulus events form amalgams in which
each stimulus enters in accordance with its salience and its response eliciting
properties. Amalgams are both formed and
organized by the brain into networks that organize them rationally into what we
might call knowledge. Hence, it is not
just the strongest but all stimulus events that impact upon what is learned and
usable in the future. The traditional ‘reinforcer’
is but the strongest of events in a situation.”
Lana provided an excellent example of an emergent behavior
early in her work with the keyboard. It was useful for caretakers and
researchers if she did not urinate any where she wished in her enclosure, so they
used a conditioning technique to train her to use a pan. Each time Lana
urinated in the pan, she received a reward.
Lana, however, did not just learn that she would be rewarded
for urinating in the pan. Instead, she also concluded that it must be the
putting liquid in the pan that resulted in a reward. When she could not no
longer urinate, she would spit in the pan and then look expectantly for a
reward even though that behavior had not been reinforced at any time. Dr.
Rumbaugh explains, "It is the dynamic flow of contexts, stimuli, and much
else—it is the integrating of all these things that allow the brain to work.”
The Language Research
In 1980, Georgia State University built the Language
Research Center, founded by Dr. Rumbaugh, and where he served as director until
2001. He and his team, as well as researchers from around the world, carried
out numerous studies on nonhuman primates. A bonobo named Kanzi taught them a
great deal about comprehension. Kanzi was at the Language Research Center as an
infant, but not as the subject of language training or research. An adult
female named Matata acted as his mother, and he was always there with her.
Matata was not a particularly good student, but, to everyone’s surprise, Kanzi
Although no one had been directly teaching Kanzi, he was
paying attention. When Matata left, he needed to communicate with humans to get
the things he wanted. To the amazement of all of the researchers and
caretakers, he did so with the lexigram keyboard. "Researchers have learned
that giving a rich, logically structured, and relevant life to a young ape will
allow it to organize its intelligence in ways that are unique and exciting,”
Dr. Rumbaugh says. Today, Kanzi’s son Teco is surprising the researchers who
work with him at the Iowa Primate Learning Sanctuary.
After a life of working so closely with animals, it is not
surprising that Dr. Rumbaugh’s views about their treatment have shifted
drastically. During World War II, he spent time working on a farm where "animals
were chattel that were either good business or bad business for the farm.” Now,
his views about animal treatment are far more complex and nuanced: "All
animals, including farm animals and animals in the wild, should be treated with
more respect and care for their needs. Farm animals should not be raised in
pens they can’t even turn around in.
That is wrong to do. Hogs need to walk around and root for food. The
same is true of chickens. These animals have their own sense of what is going
on, and they are distressed. We should strive to be more humane.”
Hopes for the Future
As for the future of research, Dr. Rumbaugh would like "to
see the whole of salience theory explored for predicting what animals and we
will learn and what they will do with what they have learned.” He considers
"the work of Charles Menzel illustrative” of the kind of research that he likes
to see at the Language Research Center. Dr. Menzel "has shown that Panzee, a
chimpanzee, has a superlative ability to observe where items are hidden on the
forest floor and ask for their retrieval even days later by a person who does
not know where they were hidden. She remembers what is in the bags—up to 20 of
them—and where they are hidden. She asks for them in order of their food value
(to her) and the quantity of food in them. She directs the person by pointing,
using body orientation, and vocalizations.”
Michael Beran and others have shown that Panzee’s comprehension of
spoken language is superior to her comprehension of lexigrams. As the research
team learned with Kanzi, when a dedicated staff raises a chimpanzee "in a
language-rich environment” they are capable of more than scientists thought
possible just a few decades ago.
Although current studies with the apes are quite different from the language
acquisition studies of prior years, they still inform the basic question, "What
do these symbols mean to the apes?”
Beyond the specifics of future research, Dr. Rumbaugh says,
"It is myopic when people conclude that there is nothing of consequence to
learn from comparative studies with animals.
We are not as unique as once thought.
And early rearing is very important for the development of optimum
intellectual development both in humans and animals. I strongly believe that comparative
psychological studies remain basic to understanding human psychology.”
To learn more:
Book: Dr. Rumbaugh’s new book is available on Amazon at
All proceeds from the book go directly to support the apes.
Rumbaugh, D. M.
(2013). With apes in mind; Emergents,
communication, & competence. Retrieved from http://www.withapesinmind.com/
Rumbaugh, D. M.,
King, J. E., Beran, M. J., Washburn, D. A., & Gould, K. L. (2007). A
salience theory of learning and behavior—With perspectives on neurobiology and
cognition. International Journal of
Primatology, 28, 973–996.