Black-tailed deer
(Odocoileus hemionus columbianus)

all flatten the heads of their female children near the falls,
William Clark

in the evening the hunters returned to Camp had killed 4 Deer.
Joseph Whitehouse

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These four deer posed near the Corps' camp of October 21.
Photo date: November 8, 2008

four deer with black tails on the side of a hill with basalt rocks and sagebrush

Cowlitz Area Baby (Chinook)

all their heads are compressed into the same form…. This singular and deforming operation is performed in infancy in the following manner. A piece of board is placed against the back of the head extending from the shoulders some distance above it; another shorter piece extends from the eye brows to the top of the first, and they are then bound together with thongs or cords made of skins, so as to press back the forehead, make the head rise at the top, and force it out above the ears.
Patrick Gass

Historical painting of a Cowlitz baby in a Chinook head flattening press

Painting by Paul Kane in 1847.