Any behavior exhibited by young children that is taken as evidence of the early emergence of intelligence will, when subsequently exhibited by nonhumans, be interpreted by many humans as a set of simple stimulus-response associations lacking cognitive processing, whereas the stimulus-response explanation will rarely be used to re-interpret the behavior of the child.
To arrive at the edge of the world's knowledge, seek out the most complex and sophisticated minds,
put them in a room together, and have them ask each other the questions they are asking themselves.