【英语时差8,16】乌鸦偷窃(在线收听) |
Native American stories and legends depict crows as witty and tricky.
Modern behaviorists agree; crows are one of the more intelligent bird species. That intelligence allows them to be crafty survivors as well as, to put it bluntly, thieves.
Maybe our interest in the crow comes from our similar habits. Like us, crows can be generous. They are cooperative breeders who mate for life. They live in family groups composed of several generations and young birds help out with chores, including nest building, feeding hatchlings and chasing away predators.
Like humans, crows also have a dark side. When food resources are at a premium, the have-nots find ways to take from the haves. When crows forage for small bits of food that can be eaten quickly, there isn't a problem with food theft.
Researchers studying Northwestern crows found that when a crow has a large meal, like a crab or clam, it becomes a pilfering target. These are not just chance robberies. Crows are always on the lookout for others to rob, and they alter their tactics depending upon whether their victim is related or not.
They are polite to kin, sidling up beside them in an effort to get a handout. Eventually the related bird will give in and share its food. With non-related individuals, all feeding etiquette is tossed aside.
Robbers are aggressive and intimidate their victims with vocalizations and physical contact to get their way. It's not surprising that crows have fascinated both laymen and scientists for centuries. In some ways they are a reflection of ourselves. We can only hope not to follow their bad examples. |
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