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Microevolutionary trends in the dentition of the Red fox (Vulpes vulpes)   总被引:1,自引:1,他引:0  
Microevolutionary trends in dental traits were studied in a Polish population of the Red fox, Vulpes vulpes (Linnaeus, 1758). Changes in qualitative and quantitative traits over a 70‐year interval were analysed in 1453 museum specimens collected between 1927 and 1996. Over that period, there were qualitative trends towards increasing complication of occlusal crown surface in posterior premolars (i.e. P4, P3, P4) and I3. Other cheek teeth did not undergo directional change. Changes in trait correlations were assessed using samples from the 1960s and 1990s. The correlations between C1–C1 and M1–M2 increased, while correlation values in the incisor region (I1–I2, I1–I1, I1–I2, I3–I2), carnassial region (P4–M1, P4–M1 and M1–M1) and in P2–P1 decreased. These changes may be related to increasing dietary opportunism of the Red fox during the 20th century.  相似文献   
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Frequency distributions of dental morphotype characters (groups of morphotypes from A to S) in 43 red fox Vulpes vulpes (Linnaeus, 1758) populations from the Holarctic region were analysed. Definite but different geographical gradients in morphotype dental patterns were found both in the Palearctic and Nearctic. In the Nearctic, a great number of characters present geographical gradient related to longitude whereas, in the Palearctic, gradient relates to latitude. Mean annual temperature and mean annual sum of precipitations play a significant role in shaping the geographical variation of morphotype characters. The shape of the teeth in the centre of the morphogenetic field is more heavily geo-climatically conditioned than the morphotype characters in the teeth at the ends of the cheek teeth field. There was an attempt to reconstruct the evolutionary changes in the morphotype dental pattern in the V. vulpes line. The morphotype pattern in the red fox dentition partially follows the phylogeographical evolutionary trends in Canidae in the northern hemisphere. However, the picture of morphotype variation is influenced by both earlier episodes of human interference (reintroductions of foxes in North America) and the recent phenomenon of heavy opportunism of the species.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 61–84.  相似文献   
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