The firm followed up with Petman, a two-legged prototype that applies the same technology to human-style walking.

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The man who found a human ear while walking a dog in an Aylesbury graveyard says he is in "disbelief".

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Onscreen you see a live shot of you holding the book, which now bears a superimposed animation of a walking human skeleton, a flexing dinosaur, and so on.

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The system is evidently able to distinguish between vehicles, animals, and humans -- and it can even differentiate between different types of human activity, including walking, running, and digging.

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The most extraordinary thing about walking with elephants, however, is that other wild animals are unfazed by human presence.

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The walking-stick has a whalebone and ivory top decorated with a carving of a human skull.

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