Vasil’ev A.G., Vasil’eva I.A., Chibiryak M.V., Trapezov O.V. 2024. The three-dimensional shape changes of the American mink (Carnivora, Neogale) skull under aggressive and tame behaviour selection // Russian J. Theriol. Vol.23. No.2. P.196–211 [in English].
Aleksey G. Vasil’ev [vag@ipae.uran.ru], Irina A. Vasil’eva [via@ipae.uran.ru], Mikhail V. Chibiryak [chibiryak@ipae.uran.ru], Institute of Plant and Animal Ecology Ural Branch of the RAS, Yekaterinburg 620144, Russia; Oleg V. Trapezov [trapezov@bionet.nsc.ru], Federal Research Center Institute of Cytology and Genetics Siberian Branch of the RAS, Novosibirsk 630090, Russia.
doi: 10.15298/rusjtheriol.23.2.09
ABSTRACT. Domestication morphogenetic effects resulting from long-term (16–17 generations) selection based on characters of defensive behavior in the American mink, Neogale vison (Schreber, 1777), were studied. A comparative study of the size and shape variations of the skull among obtained experimental mink strains (aggressive and tame) using 3D geometric morphometrics was carried out. The control was a non-selected minks kept in parallel. Samples of wild American and European minks (Mustela lutreola L., 1759) were used to assess the extent of the changes that occurred. In the presence of pronounced sexual dimorphism in size in all groups, a significant decrease in the skull size of tame minks was revealed. The greatest differences in the skull shape were found between aggressive and tame minks. They are comparable to the differences between cage and wild American minks, exceeding half of the interspecific differences. Tame minks exhibit skull changes in accordance with the domestication syndrome: relative shortening of the facial part, an increase in height in the frontal bone area, narrowing of the between-orbit interspace, reduction of canines. The level of morphogenetic rearrangements of the skull shape between aggressive and tame minks as a result of selection is quite high and comparable to microevolutionary transformations. Selection based on behavioral traits led both tame and aggressive minks to destabilization of skull development, which is consistent with the theory of destabilizing selection by Dmitri Belyaev.
KEY WORDS: selection, defensive behavior, Neogale vison, skull variability, postnatal morphogenesis, geometric morphometrics.