Nobody can hold a grudge like an elephant. The animals live in close-knit social groups, and are able to identify at least 30 of their relatives. Their incredible capacity to remember also plays into the fact that, well, few animals can hold a grudge quite like elephants. One study that looked at a herd of African elephants found that the animals reacted negatively to the scents of a nearby tribe whose members sometimes slaughter them. Elephants have also been known to remember human abusers several years afterward. More recently, a herd of Indian elephants refused to leave the site where one of their members was struck and killed by a train, damaging several structures along the way.
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