Pepperberg is best known for her work with a male African grey parrot named Alex. Alex was able to learn to identify and categorize objects, associate words with their meanings, and comprehend simple sentences. Pepperberg and her colleagues demonstrated that birds can learn and use human language in ways that were previously thought to be unique to humans.
In addition to her research on parrots, Pepperberg also conducted experiments with other species, including pigeons and dolphins. She has also lectured and written extensively about her work.
Career
_Early work:_
Pepperberg became interested in animal learning and communication during her time at the Bronx High School of Science, after reading about the work of animal psychologists such as John B. Watson and B. F. Skinner. When she was 18, she worked with rats and pigeons in a summer research program at the Albert Einstein College of Medicine. At the Massachusetts Institute of Technology, where Pepperberg earned her Bachelors and Master's degrees in Chemistry she met neuropsychologist Louis Herman, and became involved with the dolphin-communication project at the New York Aquarium. For over 20 years, Pepperberg has also participated in field studies of various wild parrot populations in Africa, Australia, South America, and Central America.
_Grey parrots:_
In the 1970s, Pepperberg began working with African grey parrots at the Lincoln Park Zoo in Chicago, Illinois. She initially chose parrots as a subject because they were known for their exceptional abilities at vocal imitation. She trained Alex using an operant conditioning technique called shaping.
Initially, Alex learned to associate spoken words with objects, actions, and properties of objects as well as colors, shapes and numbers. Pepperberg found that Alex was able to learn the meanings of new words and apply them in novel situations, indicating that he understood their meanings rather than simply memorizing them. Alex also showed an understanding of object permanence and the concept of zero.
Alex could identify various objects by touch, even if he couldn't see them, and he could differentiate between objects based on their color, shape and material composition. When offered three objects and asked which one was different from the others, he could answer correctly about 80% of the time. He could also correctly categorize previously unseen objects into familiar categories, such as "fruit" or "vegetable".
Pepperberg later showed that Alex could produce strings of words. Although some researchers argue that the parrot was merely "echolalic", and did not actually understand what he was saying, Pepperberg believes that Alex was genuinely creative in his use of language. She pointed out that he often "labeled" objects correctly without being prompted, and that his combinations of words were not always meaningful in human language.
The most famous example of this is Alex telling Pepperberg that her hat was a "banana": when asked what his favorite toy was, he sometimes gave the answer "key", but occasionally also gave the answer "banana". It turned out that Alex actually meant that Pepperberg's hat looked like a banana, something he had apparently learned by watching her put bananas in a bowl that was roughly the same shape and color as her hat.
The Alex Foundation
In 1995, Pepperberg founded the Alex Foundation to carry on her work with parrots. In addition to her research on Alex, Pepperberg also works with other African grey parrots and collaborates with other researchers studying various aspects of animal cognition.
In film
Pepperberg's work with Alex has been featured in several documentaries and educational programs. She has also been interviewed for numerous articles, books and documentaries, including the BBC wildlife documentary series titled ''The Life of Birds'', by David Attenborough.
''Alex & Me'', a 2014 documentary about Pepperberg and her work with Alex was chosen as one of 2015's top ten animal films by ''Good Planet'', a nonprofit dedicated to producing film content to foster a sustainable and just world.
Alex was one of the animals featured in _Meet the Robinsons_, a 2007 science fiction animation film by Walt Disney Pictures. The fictional ''Robinson Family'' is depicted keeping several parrots as pets, including one named _Carl_ who is able to have normal conversations with humans and is portrayed with an intelligence matching that of adult humans.
Pepperberg's work with parrots is referenced in several works of popular culture, including the science fiction novel _Spinoff_, by William Sleator, and _My Life with the Chimps_ by Jane Goodall.
Awards and honors
For her work with Alex, Pepperberg has been recognized by numerous scientific organizations, including the International Society for Comparative Psychology, the American Psychological Association, and the American Association for the Advancement of Science.
Pepperberg has received several awards including:
- The MacArthur Fellowship in 1991.
- The Kalbfleisch Award for research in animal cognition and communication from the New York Academy of Sciences in 1994.
- The Lifetime Achievement Award for her "outstanding contribution to the understanding and appreciation of companion parrots" from the Association of Avian Veterinarians in 1995.
- The Honorary Doctorate Degree of Humane Letters from MacMurray College in 2002.
- The Distinguished Primatologist Award from the Boston chapter of the American Society of Primatologists in 2004.
- The Lifetime Achievement Award for her scientific accomplishments and contributions from The Academy of Distinguished Alumni from the Albert Einstein College of Medicine of Yeshiva University in 2007.
- The Richard W. Thorndike Award for Achievement in Experimental Psychology in 2008.
- The WIRES Australia Conservation Award for her international recognition in the field of parrot research in 2010.