Animals tend to have certain characteristics that they generally stick to. Crows fly, and opossums play dead. That's probably why you've never seen a crow playing possum.
When you shoot at a crow and it crashes down to the ground, common sense and past experiences have taught us that it will stay there. But that's not always the case; sometimes it's just a case of a crow playing possum.
We've already found out that turkeys can come back from the dead, and if they can, why can't crows.
I think that may be more insulting to the hunter to make him think that he's killed his intended game and then fly away just when he tries to collect than for the crow to just keep flying like nothing has happened. Whatever the case it definitely makes for an interesting day of hunting.
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