Very fascinating.. The link you posted seems to be expired. Here's another reference.
Now, I understand the part about bees signaling they have found explosives. But how do they get them to show where the explosives are? At best they can only indicate their presence within some radius of the hive. The average foraging range of honey bees is 1 km.
Or maybe they can afix a GPS transmitter or recorder to them.
Honeybees can communicate both distance and direction to their hivemates. Interestingly, this depends upon an abstract analogy between the prefered direction picked out by gravitation at the surface of the Earth, and the position of the Sun. This has been known since Von Frisch 1947. See (modulo the usual caveats about the instability and lack of quality control at WP) http://en.wikipedia.org/wiki/Bee_learning_and_communication, or even better, see one of the books on honeybee communication.
However, note that the quoted article shows that the waggle dance is not involved in how these bees have been trained to signal to their human masters the presence of explosives (reread Ivan's quotation above).
Interesting about honey bees, indicating range and direction to other bees. I recall that too, from videos I had seen in grade school. I wonder how well we understand bee's signals. Can we accurately predict their range and direction, from their behavior?
What happens when different workers find several sources of nector? Each may indicate a different range and direction to fly.
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