Fractal analysis of cranial sutures in the genus Arvicola (Rodentia: Arvicolidae)

CASINOS, ADRIÀ; CASSINI, GUILLERMO HERNÁN; VENTURA, JACINT

Manchester

Encuentro; Society for Experimental Biology Annual Meeting; 2014

Society for Experimental Biology

Cranial sutures (frontal-parietal, parietal-parietal, interparietal-parietal) in adultspecimens of Arvicola scherman (fossorial) and Arvicola sapidus (semiaquatic) were studied with fractal analysis in order to elucidate whether digging activity has some effect on the suture structure. The specimens were photographed in dorsal view with a 6 Megapixel digital camera. Using the ImageJ software, sutures convolution were traced and saved as a TIFF files. Box counting fractal dimension (D) was obtained with FracLac 2.5 Release 1d?ImageJ Plugin, using two pixels as a minor unit, 45% of foreground pixels as a major unit and a mean D of four repetitions calculated in batch mode. Intraespecific differences between sutures and interespecific difeerences within sutures were analysed by ANOVA procedures and post hoc Tukey?st-test. Considering both species separately, the fractal dimension of the suture parietal-parietal was bigger than the fractal dimensions of the other sutures. When comparing both species, the interparietal-parietal and frontal-parietal sutures of A. sapidus showed bigger fractal dimensions than those of A. scherman. These differences seem to be related with the different cranial shape of both species, since A. scherman shows a shorter and wider skull than A. sapidus, in correspondence with the use of this structure as a digging tool in the former species.