They do seem to. I've ended up making a sort-of catch all fowl stock a couple of times from the bones of squabs, pheasant, and regular supermarket chicken. I saw no reason not to toss the squab heads into the stock pot with the rest, and the heads always seemed to find their way to the top. The only fowl that's ever really squicked me was a black chicken. I saw it in the Korean grocery store near work and thought, "Wow! A *BLACK* chicken! I gotta buy it!" After a couple weeks of eyeing the thing in my freezer, I realized, "Um... That's a black chicken. It looks like ass. I have to eat it." When I finally did thaw it and eat it, I ignored everything I read, all of which told me to turn the thing into soup. I, like a doofus, spatchcocked it and roasted it. Ever seen black fat (glistening on black meat, under black skin)? *shudder* It too came with its head on, which also ended up in a stock pot. That was also gross. From now on, I only eat chicken-colored chicken.