In the Rocky Mountains, what local selective driver might favor Willow Flycatchers genetically predisposed to earlier breeding?
Answer
The necessity for earlier snowmelt timing to match insect hatches
The evolutionary pressure exerted by climate change is spatially variable, manifesting differently based on local ecology. In high-elevation areas, such as the Rocky Mountains, rising temperatures lead to earlier snowmelt. Therefore, birds whose genetic makeup allows them to initiate breeding earlier—even by just a few days—gain a significant advantage. This timing alignment is crucial because it ensures the nestlings hatch when the local insect food source, which itself is linked to the earlier snowmelt, is most abundant, thereby optimizing reproductive success.
Related Questions
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