Turkey and Crow Calls

Saw turkey calls for sale in the farm & home store and couldn't imagine how they worked and was too embarrassed to ask anyone. That issue got cleared up this weekend when I got to see and toy with a variety of bird calls. Two of them, top and bottom, work on the same principle: friction creates a throaty squeak. The coffin-like "fool proof" wooden box and the disk that gets scraped with the drumstick sound alike to me, but I'm told that every turkey hunter knows the difference and has a favorite, including the kind that are like a trumpet. The gold whistle in the middle is not a turkey call but a crow call. Why anyone would want to call crows when they could call turkeys, I don't know, and was too embarrassed to ask. Demonstrated also was the very slight difference between a tom's call and a hen's -- hers is warbly, more chicken-like. I am told that upon hearing it the excited tom "will come all over himself" to find the hen. There's so much to learn.