Zig and Wikki in the Cow (Toon Books)

Spiegelman again strikes an effective balance between hijinks and education, giving the aliens straightforward but distinct personalities that play well off each other and incorporating an array of ecological facts in a way that flows with the narrative rather than intrudes upon it. Loeffler's art captures animals with a simple realism and aliens with gentle humor, and gives the whole enterprise a breezy zing.
--Booklist

Two extraterrestrial friends land on Earth in the center of a farm ecosystem, where an argument forces them to separate, only to be brought back together in the stomach of a cow.