What happened to the greenish warbler birds as they migrated from the southern portion of their range up around the Tibetan Plateau? What are two main distinctions between the East Siberian greenish warbler and the West Siberian greenish warbler? (Site 1)

Answer 1

As the greenish warbler birds migrated from the southern portion of their range up around the Tibetan Plateau, their populations split into two genetically distinct groups. These groups stopped interbreeding and evolved differently from each other over time.

The two main distinctions between the East Siberian greenish warbler and the West Siberian greenish warbler are their breeding habits and their vocalizations. The East Siberian greenish warbler breeds in small bushes or on the ground, while the West Siberian greenish warbler breeds in larger trees. Additionally, the East Siberian greenish warbler has a more complex and varied vocalization, while the West Siberian greenish warbler has a simpler and more repetitive song.