Flight-feathers: the feathers at the end of the wing, involved in flight.
Monogamous: having only one mate during a breeding season, or throughout the breeding life of a pair.
Sahel: A semiarid region of north-central Africa south of the Sahara desert that stretches across six countries from Senegal to Chad.
Steppe: a biome (or subdivision of the Earth’s surface) that is composed of a swathe of temperate grassland stretching from Romania to China.
Subspecies: a population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.
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