Crows can perform as well as 7- to 10-year-olds on cause-and-effect tasks
Another researcher thinks effects like this are due to language in humans. (Maybe not directly linked, but somewhat related)Basically the experiment was to have a rectangular room with 4 white walls, and then another box with one blue wall.Researchers put some food in the room to the left of the blue wall, showed it to a rat, then spun the rat around, and the rat got it right 50% of the time. (IE random chance.)Researchers did the same experiment with kids, and kids under 6 failed every time. Though after age 6, kids start using spacial language and can say the phrase "left of the blue wall", which implies to the researcher we use language to connect different disparate parts of the brain.More on this during this radiolab episode:
http://www.radiolab.org/story/91725-words/