Sagebrush also use “private” means of communication to warn only their family groups about insect attacks when the threat from bugs was generally low. Basically, they are using backchannels—the chemical compounds they use are complex and specific to them and their closest allies. But when the whole community is being heavily attacked, sagebrush will switch to “public” channels, emitting more universally understandable alarm calls. This tracks perfectly with something that has been known about songbirds for a long time. In peaceful places, where relatively few dangerous predators lurk, birds
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