Water actually intensifies this sense of touch, so they appear to wash their food when they are really feeling for the shape and texture of the object.
(they; to wash; their food; T:when they are really feeling for the shape and texture of the object) (they; are really feeling; for the shape and texture of the object)
they they
to wash are really feeling
their food T:when they are really feeling for the shape and texture of the object
for the shape and texture of the object