At first glance, these wallowing river-horses appear to be bulky, lazy beasts and not the fearsome predators you would expect to have a habit of mauling humans. However, with gaping mouths that can open four feet wide and swinging sledgehammer heads, as well as the fact that they can outrun us on land, these highly aggressive animals have plenty of scope for destruction and are considered one of the most dangerous of African animals.
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