Tricky Cromagnon

Bison-mammoths

1. Early cave art researcher Henri Breuil copied this image of overlapping bison and mammoth from the walls of Font-de-Gaume in France.
2.  Unlike other bison-mammoths that depict two distinct but overlapping images, this carving from a spear-thrower features one image that can be seen two different ways. Above, the artifact in its natural state. Below, red ovals highlight the position of the two eyes. 
3. The two sides of a figurine from a site near Cambrai show very different details. On one side (left), the high back leg and short front leg are characteristic of depictions of bison. On the other, the tall straight front leg and grooves depicting long hair in the midriff are typical of mammoths. (Image courtesy of Duncan Caldwell)

World's Oldest Optical Illusion Found? >>   blogs.nationalgeographic.com

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