Nanova O.G. 2015. Morphological variation and integration of dentition in the Arctic fox (Vulpes lagopus): effects of island isolation // Russian J. Theriol. Vol.14. No.2: 153–162 [in English].
Olga Nanova [nanovaolgag@gmail.com], Zoological Museum, Moscow State University, Bolshaya Nikitskaya str. 6, Moscow 125009, Russia.
ABSTRACT. We examined geographic variation in the shape of lower and upper rows of cheek teeth and variation in their morphological integration in Arctic foxes Vulpes lagopus (L., 1758). We found similarity in the structure of the variation in shape and morphological integration. Mednyi Island Arctic foxes (V. lagopus semenovi Ognev, 1931) were distinct from the other Arctic fox populations studied in terms of both the shape of cheek tooth rows and correlation of structure. Bering Island Arctic foxes (V. lagopus beringensis Merriam, 1902), which are genetically similar to Mednyi Island foxes, were closer to mainland Arctic foxes with respect to the shape of cheek tooth rows and modular structure. Elongation of the edges of both lower and upper carnassials, molar enlargement, and coordinated rotation of premolars lingually were observed in Mednyi Island Arctic foxes when compared with mainland Arctic foxes. The modularity of lower and upper cheek tooth rows was studied. Two modules were found in both lower and upper tooth rows. Lower tooth rows comprised premolar and molar modules. In upper tooth rows, molars with the fourth premolar (the carnassial) and small premolars formed two distinct modules. Masking of developmental integration by functional integration was shown for upper tooth rows of Arctic foxes.
KEY WORDS: Arctic fox, geometric morphometrics, island isolation, modularity, morphological integration, Vulpes lagopus.