美国科学60秒 SSS 2013-02-07（在线收听）

 　　Adult ants communicate with pheromones, touch and even sound. Now researchers have discovered that developing ants called pupae have their own distinctive calls, which identify their social status within the colony. This finding is in the journal Current Biology. Ants rasp and chirp by scraping a spite on their waist against a ridged section of their abdomen, but developing larvae are silent. So ants recognise them by chemical cues, size, shape and even squishiness. The teenage versions of ants, the pupae, have hard outer shells that lack pheromones. However, the pupae do have fully formed sound organs. The researchers thus record the audio from the pupae and discover clicking noises. The pulses' frequency and intensity are more like the adult worker's stridulations than the queen ant's sound. The pupae's snaps are brief because their cases keep them from moving much. Still the noise appears to work, when the researcher disturb the nest, the adult ants rescue noisy pupae before the silent larvae. For ants, as for people, it pays to be the squeaky wheal.