Well, looks like symbolic thinking might be an "innovation" whose time-scale has to be pushed back (via Abiola). As I've noted before, One Great Leap ~45,000 years ago is seductive, partially because it allows multiple disciplines to focus on one time period (ie; One Leap -> One Leap Function -> One Leap Gene), but we should be cautious....

Update: Seems like the "language gene" might play a role in bird-songs! I guess nature doesn't reinvent the wheel, just retro-fits it now & then....