But precisely because the horse and the rider are in such close physical contact, it is difficult to disentangle mental influences from unconscious body signals, such as small changes in muscular tension. It remains an open question how such impressions of experienced riders can be explained. Unfortunately, experiments that rule out slight movements would be practically impossible while the horse is being ridden. As in so many cases of apparent thought transference, telepathic influences may often work together with communication through the recognized senses. In real life it is hard to tease them apart. That is why it is necessary to carry out formal experiments to find out whether telepathy really happens. Here is one example.
EXPERIMENTS WITH A LANGUAGE-USING PARROT
After Dogs That Know When Their Owners Are Coming Home was published in 1999, I received more than a thousand additional accounts of perceptive animals. Some of the most surprising of these concerned parrots. I heard over and over again about parrots that responded to their people's moods, feelings, and intentions by making appropriate comments. In some cases this ability seemed to be telepathic.
Some parrots seem to pick up their owner's intentions to go out, as described above. Some seem to know when their owners are coming home, and announce their arrival beforehand (see chapter 5). Others seem to know when particular people are calling on the telephone before the phone has been answered, announcing the caller by name (chapter 6). They ignore calls from insurance salesmen and other strangers.
The fact that parrots can use language meaningfully has been established beyond reasonable doubt by Dr. Irene Pepperberg, now at the Massachusetts Institute of Technology. She has spent twenty years training her African Grey parrot, Alex, who now has a vocabulary of around 200 words. Through meticulous experiments, she has found that Alex is capable of abstraction, and can grasp such concepts as "present" and "absent" and use the words for colors appropriately, whatever the shape of the colored object.
Before Pepperberg's research, within institutional science it was generally assumed that parrots were mere mimics, "parroting" words with no understanding. Most scientific studies of human-to-animal communication were carried out with apes, using sign language. Pepperberg has succeeded in showing that parrots, although literally bird-brained, rival apes in the ability to use thoughts and concepts, and of course have the huge advantage of being able to speak. She has summarized her research with Alex and other parrots in a monumental book titled The Alex Studies: Cognitive and Communicative Abilities of Grey Parrots.9
Pepperberg's pioneering work has inspired a number of other people to do research on the meaningful use of language by parrots. One of this new generation of researchers is Aimée Morgana, an artist who lives in New York City. Her African Grey, N'kisi (pronounced "in-key-see"), had a vocabulary of around 700 words by January 2002, even though he was only four years old. Aimée taught N'kisi to use language as if he were a human child. He has learned the contextual meanings of words, and is able to use his understanding of language to make relevant comments. He speaks in sentences, of which Aimée Morgana has now recorded more than 7,000 different ones.