Some dogs live to play fetch, especially if the object of interest is a favorite tennis ball or toy. Others, like ours, fetch only when the reward is a particularly tantalizing tidbit. At least one dog, however, appears to take the enterprise seriously enough to figure out an optimal path to the target.
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Elvis is a Welsh corgi who belongs to mathematician Timothy J. Pennings of Hope College in Holland, Mich. When Elvis and Pennings go to the beach, their pastime of choice is fetch. Standing at the water’s edge, Pennings throws a tennis ball out into the waves, and Elvis eagerly retrieves it.