I have deliberately increased the colour saturation of this image for both artistic and technical reasons, the latter being that accentuating the natural colours of the sarsen allows us to appreciate more clearly how the sculptor worked the stone more than 56 centuries ago!

This beautiful and quite charming sculpture seems to me to have a distinctly bovine feel to it, which would chime perfectly with the carving of a calf (?) on the main lintel stone at the Barrow's entrance (click here to view). Both animal faces are absolutely definitely sculptures, not pareidolia.

In passing, notice how at the foot of the sculpture modern visitors have left offerings of wild flowers. West Kennet Long Barrow, after centuries of abandonment and closure, been reborn as a living sacred space.

Finally I would point out that there are in fact two faces carved onto Stone 21 West Kennet Long Barrow, for details of the other click here