i think that we will see a grown up peaches, and buck will have killed rudy, and now rudy's skeleton will bridge from up above to down below, and then they will discover that, and they will go back down to see how buck is doing, and buck will decide to come back up to the surface and live with the herd, and dinosaurs will invade up above and then the herd (including buck) will fight the dinosaurs and get them back down below where they belong, and buck will stay with the herd and they will live happily ever after until ice age 5.
Well, we'd see a more grown up Peaches being raised, but that's only half of the story, they'd need to come up with something new to attract audiences' attention again.
we need more buck, i was quite sad when he went back down, so thats a sign that he will not be in the 4th one so im sad know, but i wont know till 2012 :(
