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反對

Arboreal Birds Pigeons, Parrots, Cuckoos & Colies,lexed by the bird’s weight. Some groups have an improved grasp by the arrangement of the toes, with two pointing forward and two backward (zygodactylous feet) while others have the outer toe reversible (semizygodactylous feet) so that the birds can both grasp well and run along tree boughs.