Input (grade 10): It is now thought that the first passerines evolved in Gondwana at some time in the Paleogene, maybe around the Late Paleocene some 60 â "55 mya.
Output (grade 12): It is thought that the first passerines evolved in the southern continent of Gondwana in the Paleogene, maybe around the Upper Paleocene some 60 â "55 mya.