How does the Kevin and Kell universe relate to ours?
The relationship between the two worlds is explained in one Grand Unified Sunday Strip (GUSS) on http://www.kevinandkell.com/2003/kk1214.html Once Mankind had fled a terminally polluted Earth, the birds were forced to become intelligent to survive. The birds learned how to use the leftover advanced technology, and went back in time ten million years to create a world where humans didn’t evolve and animals became intelligent and domesticated. There are essentially two Earths, separated at the 10,000,000 B.C. mark, but mirroring each other’s development.