Very smart Crows

My friend has a very large walnut tree near his backyard. The crows will pick the walnuts and fly over and near his house to drop the walnuts in the road. The crows are hoping to get cars to smash the walnuts. Some of the very smart crows will wait on the side of the road and watch the action of the hit or miss action of the car tires. Some of the crows will nudge the walnut to another position if the car tire misses the walnut.

However, you will never see a crow get hit by a car or a dead crow on the road. Here is what is happening. There is always a crow that acts as a Sargent-of the guard, and is always perched on high, as on a telephone pole or wires acting as a lookout. And every time a car comes near, the guard screams— Karrr Kaarrr karrr!
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