The limbs develop from the '''lateral plate mesoderm'''. Limb development is highly conserved; in all land vertebrates there are only four limbs and they are always opposite each other with respect to the midline of the body. All vertebrate limbs have the same patterning of; ''stylopod'' - proximal part of the limb which produces the humerus or femur; ''zeugopod'' - intermediate part of the limb which produces the radius and ulna or tibia and fibula; ''autopod'' - distal part of the limb that produces the carpals and metacarpals or tarsals and metatarsals. Other animals also follow this limb pattern including the greatly modified bird's wing. |