PART IV: LEARNING AND PROGRESS

Chapter 15: Survival Training

1. Beyond demonstrating that animals do indeed modify their behavior in light of previous experience, little else has been proved conclusively with respect to learning. In fact, even to this date experts cannot agree on a precise definition of the term learning.

2. One of the few principles accepted by all experts is that learning depends on the accumulation of experience. Trying to quantify the relationship between experience and learning has occupied psychologists for decades.

3. To calculate the rate of learning, one must compare the improvement of performance to the growth of experience. Studies on a wide variety of species have confirmed that improving performance was a direct consequence of accumulating experience.

4. For a time, some investigators believed that by comparing learning-curve slopes of various species, they could determine the rank order of animal intelligence. Their reasoning was the steeper the learning curve, the faster the learning, and thus the smarter the species.

5. But even if two species are run through exactly the same experiment, their learning curves cannot be compared meaningfully. Since no two species are identical, designing unbiased experiments is impossible.

6. In 1973, H.J. Jerison created an index called the EQ, short for "encephalization quotient." The EQ compares the actual brain/body ratio of species to its predicted ratio. The human's EQ of 7.44 means the human brain is 7.44 times heavier than it would be mathematically predicted for a typical mammal of human body weight. This is the highest ratio of any species alive or extinct.

7. Although chimps are our closest surviving evolutionary relatives, they possess a far lower EQ (2.49) than humans. By the logic that the higher the EQ the greater the brain's information-processing capacity, it would seem dolphins (5.31 EQ) might have enough brainpower to handle language. Unlike chimps, dolphins have shown they can grasp syntax as well as symbols.

8. Should future research with dolphins show that humans hold no monopoly on spoken language, we will be forced once again to admit the closeness of our relationship with the rest of nature's species.

9. Ultimately, the only absolute distinction separating humans from dolphins and all other species may be that humans alone have a second form of language- writing.

10. If literacy, rather than speech or the opposable thumb, is the attribute that distinguishes us from all other species, it makes sense that the use of written information is the key to our evolutionary success.