<P> The Kangaroo's son, Rudy grabs the clover and returns it to Horton . The animals finally hear the Whos and realize the truth and isolate the Kangaroo for tricking them . While being praised for his integrity by his neighbors, Horton even forgives the devastated Kangaroo, and she befriends him with a makeshift umbrella for Whoville . Here, the people of Whoville and the animals of Nool gather in song and recite the chorus from "Can't Fight This Feeling". The film ends with the narrator revealing that the Jungle of Nool, or rather Earth, is just one speck, like Whoville, among numerous others, floating in outer space . </P> <Ul> <Li> Jim Carrey as Horton the Elephant, an outgoing, big - hearted, loving, sweet, and thoughtful elephant and teacher in the Jungle of Nool . Horton has no tusks, lives by himself and possesses acute hearing abilities . </Li> <Li> Steve Carell as Mayor Ned McDodd, the mayor of Whoville . He has 96 daughters, 1 son named JoJo and a wife named Sally . </Li> <Li> Carol Burnett as Jane Kangaroo, who mistrusts Horton's inquisitive nature as a threat to her legal authority over Nool . </Li> <Li> Will Arnett as Vlad Vladikoff, a Russian - accented vulture hired by the Sour Kangaroo to steal Horton's clover . </Li> <Li> Seth Rogen as Morton the Mouse, a mouse and Horton's best friend in the Jungle of Nool . </Li> <Li> Dan Fogler as the Chairman of Whoville, dedicated to Whoville tradition and mistrustful of the Mayor . <Ul> <Li> Fogler also voices Yummo Wickersham, leader of the Wickersham ape tribe brothers . </Li> </Ul> </Li> <Li> Isla Fisher as Dr. Mary Lou LaRue, a professor at Who U . </Li> <Li> Jonah Hill as Tommy, one of Horton's students . </Li> <Li> Amy Poehler as Sally O'Malley, the Mayor's wife and mother to Jojo and her 96 daughters . </Li> <Li> Jaime Pressly as Mrs. Quilligan, Jessica's mother . </Li> <Li> Charles Osgood as the Narrator </Li> <Li> Jesse McCartney as JoJo, the Mayor's son . </Li> <Li> Josh Flitter as Rudy Kangaroo, the Sour Kangaroo's son . </Li> <Li> Niecy Nash as Miss Yelp, the Mayor's assistant . </Li> <Li> Laura Ortiz as Jessica Quilligan, Mrs. Quilligan's daughter and one of Horton's students . </Li> <Li> Selena Gomez as Helga, one of the Mayor's 96 daughters . </Li> <Li> Joey King as Katie, a cute, but eccentric little baby yak . </Li> <Li> Bill Farmer as Willie, a bear and Tommy's dad . </Li> <Li> Heather Goldenhersh as a Who Girl </Li> </Ul> <Li> Jim Carrey as Horton the Elephant, an outgoing, big - hearted, loving, sweet, and thoughtful elephant and teacher in the Jungle of Nool . Horton has no tusks, lives by himself and possesses acute hearing abilities . </Li> <Li> Steve Carell as Mayor Ned McDodd, the mayor of Whoville . He has 96 daughters, 1 son named JoJo and a wife named Sally . </Li>

Who plays horton in horton hears a who