Super Nintendo:

Enter the code at the title screen. During gameplay, press Select to instantly jump to the next area.
Effect Code: Advance to next area - left, up, X, up, right, Y


Genesis:

Level skip:
On the title screen, press: A B right A C A down A B right A
If done correctly, the caveman second to the right will grin. Now, start the game, enter the first level, and press and hold A+B+C, all together. Release, hold down A, and press up. You'll skip to the next level, and you can perform the ''hold A press up'' code again to skip multiple levels if you wish.

Level Codes:
Level 2: GJFKFN
Level 3: PDPKKN
Level 4: JWNTF
Level 5: TSNFNVP