Fig. 1From: Evolution and development of the bird chondrocraniumComparable chondrocranial stages of six birds. Stages increasing in age from left to right. a Struthio sp. [25, 45], b Anas platyrhynchos [46], c Spheniscus demersus [47], d Falco tinnunculus [48], e Melopsittacus undulates [49], and f Euplectes orix [50]. Drawings by Timea Bodogán, modified from cited sourcesBack to article page