Evolutionary and climatic factors affecting tooth size in the red foxVulpes vulpes in the Holarctic |
| |
Authors: | Elwira Szuma |
| |
Institution: | 1. Mammal Research Institute, Polish Academy of Sciences, 17-230, Bia?owie?a, Poland
|
| |
Abstract: | Research into the geographical pattern of tooth size in the red fox,Vulpes vulpes (Linnaeus, 1758) in the Holarctic was conducted on a sample of 3806 skulls belonging to 41 fox populations. The Nearctic
was represented by 948 specimens (249 females, 359 males, 340 specimens of unknown sex) belonging to 13 populations, whereas
the Palearctic was represented by 2858 red foxes (1034 females, 1256 males, 568 specimens of unknown sex) from 32 populations.
In the Nearctic, the largest foxes live on Kodiak Island (V. v. harrimani) and the Kenai Peninsula (V. v. kenaiensis), while the smallest ones live in California (V. v. necator) and Georgia (V. v. fulvus). In the Palearctic, the largest foxes come from the Far East (V. v. jakutensis, V. v. beringiana, V. v. tobolica), while the smallest are from the southern borders of the Eurasian range (V. v. pusilla, V. v. barbara, V. v. arabica). In both the Palearctic and Nearctic, tooth size in the fox varies depending on the geo-climatic factors. The fox’s tooth
size confirms the general basis of Bergmann’s rule. In the Palearctic, specimens with larger teeth occur in cooler habitats
with greater seasonality. These are first and foremost Northern and Far Eastern populations. In the Nearctic, tooth size in
red foxes depends on the temperature and humidity of their habitat. Competition within the species and between species has
important impact on the variation and dimorphism of tooth size in the red fox. Both in the Nearctic and Palearctic, red foxes
from regions of sympatric co-occurrence with other closely relatedVulpes species, are more sexually dimorphic in terms of tooth size than red foxes from allopatric regions. Analysis of morphological
distance on the basis of the size of dental characteristics shows, that in the Palearctic, the foxes from India (V. v. pusilla), while in the Nearctic, the population from Kodiak Island (V. v. harrimani) are most distant from the remaining populations. Geographic barriers such as the Bering Strait, Parry Channel, Mackenzie
River, Kolyma and Omolon River systems have had a critical impact on red fox evolution. The most likely place for the evolution
and diversification of the phyletic lineVulpes vulpes seems to be the Middle East region. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|