B11

In his quarters at the University of Arizona, Alex is commenting on all that he sees. “Hot!” he warns as a visitor picks up a mug of tea. Alex spots a plateful of fruit and announces his choice: “Grape.” Alex is an African grey parrot.

 VISIT

B12

For the last 16 years, biologist Irene Pepperberg has been exploring the degree to which the bird understands what he is saying.

 BIOLOGY

B13

Alex also communicates what appear to be various feelings.

 VARY

B14

Are the parrot’s words merely a collection of sounds he emits when frustrated, or does this one-pound bird know what he is saying?

 MERE

B15

For centuries, philosophers argued that thinking and language separate humans from other species. Later, scientists had reason to be critical of claims concerning animal intelligence.

 THINK

B16

Today innovative probes of animal intelligence have convinced most scientists that other species really share with humans some higher mental abilities.

 ABLE