Crash and Eddie are two fraternal twin brother opossums that appear in the second film. These two brothers were the adopted brothers of Ellie the mammoth, but cared for her all the same, even teaching her to hang by her tail from a tree branch when she slept as they did.

Didelphimorphs are small to medium-sized marsupials, with the largest about the size of a large house cat, and the smallest the size of a mouse. They tend to be semi-arboreal omnivores, although there are many exceptions. Most members of this taxon have long snouts, a narrow braincase, and a prominent sagittal crest.

第二部《冰河世纪》中增加了一头老以为自己是负鼠的女猛犸象，还老爱学兄长把自己给倒吊在树枝上。那么负鼠又是一种怎样神奇的动物咧？

负鼠是有袋目负鼠科的通称。是一种比较原始的有袋类动物，主要产自拉丁美洲。为中、小型兽类。大多数具有能缠绕的长尾，因此母负鼠能随身携带幼鼠到处奔跑。尾毛稀疏并覆以鳞片。少数种类尾短而具厚毛。四肢短，均具5趾。拇指大，无爪，能对握。平时，负鼠喜欢生活在树上。它行动十分小心，常常先用后脚钩住树枝，站稳之后再考虑下一步动作。它们会在疾奔中突然立定不动，捕捉它们的动物往往会被这个动作吓得大吃一惊；负鼠在来不及躲避敌害时，往往装死，这不是它聪明的举动而是它被吓的暂时的休克。