| He glowered at her, and she giggled, then pecked him a quick kiss on the cheek and leaped off to another tree. |
| All subjects had participated in an earlier experiment in which they pecked at black and white symbols to procure food rewards. |
| Almost all of his grass has been pecked up by birds in search of a tasty meal. |
| Outside Pittsburgh he'd found her flowered hat floating in a pond, half pecked apart by birds. |
| It clawed, pecked and fluttered its short, stubby wings as it thrashed about to get free. |
| In this experiment, demonstrator pigeons either stepped on a treadle or pecked at the treadle to obtain a food reward. |
