Which recognized Willow Flycatcher subspecies generally tends to breed at higher elevations than *E. t. traillii*?
Answer
*E. t. wrightii*
The historical classification of the Willow Flycatcher into four primary subspecies reflects divergence across its wide North American range, with traditional distinctions based on morphology and breeding location. Specifically, the western subspecies, designated as *E. t. wrightii*, is noted for typically breeding at higher elevations compared to the nominate subspecies, *E. t. traillii*, which is found further east. This difference highlights past evolutionary matching between the subspecies and the local environmental conditions prevailing in their respective breeding zones.
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