Some animal behaviorists argue that certain animals can remember past events,

　　anticipate future ones, make plans and choices, and coordinate activities within a

　　group. These scientists, however, are cautious about the extent to which animals can

　　be credited with conscious processing.

　　(5) Explanations of animal behavior that leave out any sort of consciousness at all

　　and ascribe actions entirely to instinct leave many questions unanswered. One

　　example of such unexplained behavior: Honeybees communicate the sources of

　　nectar to one another by doing a dance in a figure-eight pattern. The orientation of

　　the dance conveys the position of the food relative to the sun's position in the sky,

　　(10)and the speed of the dance tells how far the food source is from the hive. Most

　　researchers assume that the ability to perform and encode the dance is innate and

　　shows no special intelligence. But in one study, when experimenters kept changing

　　the site of the food source, each time moving the food 25 percent farther from the

　　previous site, foraging honeybees began to anticipate where the food source would

　　(15) appear next. When the researchers arrived at the new location, they would find the

　　bees circling the spot, waiting for their food. No one has yet explained how bees,

　　whose brains weigh four ten-thousandths of an ounce, could have inferred the

　　location of the new site.

　　Other behaviors that may indicate some cognition include tool use. Many

　　(20)animals, like the otter who uses a stone to crack mussel shells, are capable of using

　　objects in the natural environment as rudimentary tools. One researcher has found

　　that mother chimpanzees occasionally show their young how to use tools to open

　　hard nuts. In one study, chimpanzees compared two pairs of food wells containing

　　chocolate chips. One pair might contain, say, five chips and three chips, the other

　　(25)our chips and three chips. Allowed to choose which pair they wanted, the

　　chimpanzees almost always chose the one with the higher total, showing some sort

　　of summing ability. Other chimpanzees have learned to use numerals to label

　　quantities of items and do simple sums.

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