Complex sentence: Of note the black-vented woodswallows are more adapted to arid and semi-arid conditions, while the white-vented are adapted to tropical/humid conditions.Therefore selection pressure will probably not result in subspecies merging.
Split into simpler sentences: Of note the black-vented woodswallows are more adapted to arid and semi-arid conditions, while the white-vented are adapted to tropical/humid conditions. Therefore, selection pressure will probably not result in subspecies merging.