Ontogenetic changes in the skull of the carboniferous tetrapod Greererpeton burkemorani Romer, 1969

A partial growth series, representing a 4.4-fold increase in the linear dimensions of the skull of Greererpeton burkemorani Romer, 1969, reveals that allometric changes are limited to: (1) an increase in the area of some circumorbital bones (primarily the lacrimal, jugal, and postorbital); (2) a small increase in the width of the skull table across the tabulars; (3) a decrease in the length and an increase in the width of the braincase relative to skull length; and (4) an anteromesial shift in the stapedial foot plate relative to its distal flattened plate. The position of the orbits does not appear to shift posteriorly over the growth interval studied. As the proportions of the braincase change relative to the remainder of the skull during ontogeny, so too do the proportions of the stapes for it to maintain its role as one of the principle supports for the back of the braincase.