Ellie is a female woolly mammoth, whom Manny, Diego, and Sid meet during their migration to escape the flood in the second movie, Ice Age: The Meltdown. She is also one of the leaders of The Sub-Zero Adventure Group. It was revealed that when Ellie was young, she was separated from her herd during the ice age. She came across two possums named Crash and Eddie, along with their mother. She later forgot her origins and thought that she was an opossum. Manny met her when he was afraid that he truly was the last mammoth, and he was overjoyed that he had found another of his kind, but got a surprise when he saw that Ellie believed that she was an opossum. Nevertheless, he and his herd (or rather, Sid) welcomed Ellie and her brothers to travel with them. During this time, Ellie displayed the mannerisms pertaining to an opossum as well as insisting (despite obvious proof that she was not a possum) and this was weighing heavily on Manny's patience, namely when she claimed that the act of bravery that he had done of fighting off the sea reptile Cretaceous was dumb. Soon, Manny got his time to be alone with Ellie when he and Ellie went for a walk through a wooded area, where Ellie had a flashback that told her of her past. Upon remembering this, she knew that she was a mammoth, but was soon angered at Manny for implying that they must mate in order to save the mammoths from extinction, but in time, she apologized for over-reacting. She and Manny also slowly fall in love now and the next morning when they resumed travel, this affinity did not seem to end. Soon, however, this new "herd" reached a horrible obstacle between them and safety from the oncoming flood: a field of geysers, which Manny explained must be crossed, but Ellie would not listen: she and her brothers felt that they must go around. But this proved to be disastrous: as they were trying to reach their destination, some rocks caved down and nearly crushed Ellie and her brothers, but trapped them instead in a sort of cave. Manny rescued Ellie, for the water was flooding into the cave where she was trapped and had nearly drowned Ellie. She and Manfred escaped and regrouped with the others, but faced another problem, for the waters were still rising. Eventually, however, the waters subsided and to top it all off, a herd of mammoths made their way into the valley. Manny thought that because the mammoths had come, that Ellie would not want to remain with him. Manfred was persuaded otherwise by Sid and Diego and soon caught up with Ellie and confessed his feelings, saying that he wanted to be together not because they had to be, but because he himself wanted to. Ellie accepts him as her mate. The mammoths trumpet while Manny and Ellie embrace. Manfred and Ellie decide to stay with their old friends, taking along Sid, Diego, and the possum brothers.
In Ice Age: Dawn of the Dinosaurs, she and Manny are mates and Ellie is pregnant with their first child. When they find the Dinosaur World under their feet, they have to go in and search for Sid in Lava Falls. When very close to Lava Falls, Ellie goes into labor and gives birth to Peaches (which was the code word for if Ellie went into labor on the trip). When they return to the surface, Ellie introduces Peaches to her new home.
She will make her guest appearances in other projects outside of the Manny, Sid, and Diego's Adventures Series, such as Danny Phantom's Adventures of Short Circuit 2 and the several episodes of Captain Charles T. Baker's Adventures of Kim Possible.
Ellie is voiced by Queen Latifah.