Some students suggested that ants do not make sounds, what do they rely on to convey information? So the students of an inquiry group designed an inquiry experiment for this problem.

(1) ① choose an ant hole, at the same time these frightened ants to feed for a period of time;

② will be three small stones in a container of water, to create three small islands A, B, C, small islands connected with two small wooden strips (as shown in the figure), so that the ants can only be made by the small wooden strips of "bridge" to reach the other islands from a small island. A small island to the other islands.

3 will be three small stones in a container of water, the creation of three small islands A, B, C: Island C (food), Island A (no food) to form a control experiment and Island B to put the ants (no food). C island of the ants found food, the ants on the island of A, "empty-handed" and returned.

4 After a period of time, the "bridge" ① and "bridge" ② were switched, and it was found that the ants still climbed up to island A along the bridge ①, but could not find any food on island A. Few ants reached island C along the bridge ②.

Results analysis:

Step 3: The ants will follow the bridge to island C to get food.

Step 4: The ants will walk along the odor of the switched bridge and reach island A along bridge ①.

Step 5: The ants move in a disorderly manner after spraying some smelly substance.

(3) The conclusion of the experiment: ants rely on odor to communicate.

The answers are: (1) ① an ant hole; ③ no food;

(2) ①; A; ①;

(3) odor;

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