“What advantages could a baby bird have from its eye color being different than the adults of the species?”
The blue eyes of baby crows, baby blue jays and two crane species (Whooping cranes and Siberian cranes) are different from the adults of their species. The different color tells other birds of their own species that these babies are helpless and they have parents that take good care of them. The babies' eye color is usually enough to make adult birds of their own species leave them alone.
Thanks to ornithologist Laura Erickson for sharing these thoughts!