Ray Romano

Manny (voice)

John Leguizamo

Sid (voice)

Denis Leary

Diego (voice)

Goran Višnjić

Soto (voice)

Jack Black

Zeke (voice)

Cedric the Entertainer

Carl (voice)

Stephen Root

Frank / Start (voice)

Diedrich Bader

Oscar (voice)

Alan Tudyk

Lenny / Freaky Mammal / Dab (voice)

Lorri Bagley

Jennifer (voice)

Jane Krakowski

Rachel (voice)

Peter Ackerman

Dodo / Freaky Mammal (voice)

P.J. Benjamin

Dodo (voice)

Josh Hamilton

Dodo / Aardvark (voice)

Denny Dillon

Glyptodon (voice)

Mitzi McCall

Glyptodon (voice)

Tara Strong

Baby Start (voice)

Chris Wedge

Dodo / Scrat (voice)

Kristen Johnston

Sylvia (voice) (uncredited)

Darin De Paul

Additional Voices (voice) (uncredited)

Dann Fink

Dodo (voice) (uncredited)

Patrick Pinney

Various Mammals (uncredited)

Phil Proctor

Various Mammals (uncredited)