A recent study on crow intelligence was released recently observing crows at an intersection. There was a distinct pattern in which they took paint samples from crows that had been run over and matched to vehicle types. It was observed that nearly all the paint samples had come from trucks, not passenger cars. The scientists researching the incident explained it as the crows had established look out birds so that they could alternate feeding on trash and road-kill, while the others looked for danger. The lookouts, while able to produce vocalizations for “cawr, cawr, cawr”, found “truck, truck, truck” much more difficult.