Mimicry in Cardueline finches

Today Matt Young told me about David Sibley’s recent post on vocal mimicry in Pine Siskins. The surprise to me (and to Sibley and others) was not that Pine Siskins infringe on other birds’ copyrights, but rather that this fact had gone unreported in the literature for so long. Actually it hadn’t just gone unreported; it had been refuted. [Read more]