 CONT: The first animal to step on Scrat in the opening is a mammoth,  yet no mammoth is visible in the long shot of the crowds of animals.  In fact, no mammoth other than Manfred is seen throughout the  sequence. With this, a large bird also steps on Scrat, but no birds  are seen in the crowds. We also only see two legs of each animal  stepping on Scrat even though three of them are quadrupeds.