One thought on “Erich Jarvis (Duke/HHMI) Part 3: Genes specialized in vocal learning circuits”

  1. The work by Okanoya is far from conclusive; I consider it deeply flawed. For my comments on that, please click HERE.

    As for vocal learning evolution being constrained by predation, I’d like to see examples of predators of birds stalking by sound. My understanding is that hawks use sight. I’ve never seen cats stalking a singing bird. Cats when hunting birds also seem only to use sight. Snakes hunt by odor.

    Cats do use sound to locate rodents. Mice — needless to say far from the top of the food chain — have also been claimed to be vocal learners — by Dr. Jarvis.

    Okanoya cites field studies that are supposed to show increased risk of predation associated with vocalization. One study was about frogs and bats, the other egg raiding at bird nests. Neither has any relevance to male birds seeking mates.

    Gesturing is used in communication and — as with sign — can also serve to externalize Language. Gesturing clearly is not essential to Language. Even those who in conversation generally weave their hands in the air as if conducting an orchestra can drive a car while speaking to passengers without any unusual risk of accident. Most Language is internal and no one normally accompanies that with hand movement or vocalization. Any such activity is considered as pathological.

    Chimpanzees with training do achieve a limited ability to communicate by gesture. The chimps don’t learn Language through sign.

Leave a Reply

Your email address will not be published. Required fields are marked *