Figure 8From: The buccohypophyseal canal is an ancestral vertebrate trait maintained by modulation in sonic hedgehog signalingInterrelationships of fossil and extant vertebrates. Red lines indicate the closure of the buccohypophyseal canal. Topology based on data from literature [2, 38, 46, 57, 58]. actinopt., actinopterygians; euchon., euchondrocephalians; neosel., neoselacians; tetrapodomor., tetrapodomorphs.Back to article page