Clavicles

Some articles on clavicles, clavicle:

Dinosoor - Origin of Birds
... with the key piece of evidence being the supposed lack of clavicles in dinosaurs ... However, as later discoveries showed, clavicles (or a single fused wishbone, which derived from separate clavicles) were not actually absent they had been found as ...
Massospondylus - Paleobiology - Gait and Range of Motion
... Since the discovery of rudimentary and nonfunctional clavicles in ceratopsians it was assumed that these shoulder bones were reduced in all dinosaurs that did not have true ... that Massospondylus possessed well-developed clavicles that were joined in a furcula-like arrangement, acting like a clasp between the right and left shoulder blades and prohibiting any rotation of these ... This discovery indicates that the clavicle reduction is limited to the evolutionary line leading to the ceratopsians ...
Origin Of Birds - Research History - Heilmann and The Thecodont Hypothesis
... However, Heilmann noted that birds had clavicles (collar bones) fused to form a bone called the furcula ("wishbone"), and while clavicles were known in more primitive reptiles, they had not yet been recognized in ... is not reversible, Heilmann could not accept that clavicles were lost in dinosaurs and re-evolved in birds ... Clavicles are relatively delicate bones and therefore in danger of being destroyed or at least damaged beyond recognition ...
Clavicle - Evolutionary Variation
... The clavicle first appears as part of the skeleton in primitive bony fish, where it is associated with the pectoral fin they also have a bone called the cleithrum ... In such fish, the paired clavicles run behind and below the gills on each side, and are joined by a solid symphysis on the fish's underside ... interclavicle between the base of the clavicles, although this is not found in living amphibians ...
Gerhard Heilmann - The Origin of Birds
... However, Heilmann noted that birds possessed clavicles fused to form a bone called the furcula ('wishbone'), and while clavicles were known in more primitive reptiles, they had not yet been ... that evolution is not reversible, Heilmann could not accept that clavicles were lost in dinosaurs and re-evolved in birds, so he was forced to rule out dinosaurs ... for the next four decades, despite the discovery of clavicles in the primitive theropod Segisaurus in 1936 ...