Nest construction is more diverse in the Hirundinidae than in any other family of oscine birds. To explore the evolution of this diversity, we superimposed nest data on a DNA-hybridization phylogeny of 17 swallow species. Nest construction is tightly linked to the inferred evolutionary history.
Bird song is a complex behavior that requires the coordination of several motor systems. Sound is produced in the syrinx and then modified by the upper vocal tract. Movements of the hyoid skeleton have been shown in the northern cardinal (Cardinalis cardinalis) to be extensively involved in forming
اكتب أحد الأعراض أو المرض واقرأ عن الأعشاب التي قد تساعد ، واكتب عشبًا واطلع على الأمراض والأعراض التي تستخدم ضدها. * تستند جميع المعلومات إلى البحوث العلمية المنشورة