Summarized the results of previous studies, the body size of Niviventer coxingi seemed to be correlated with altitude. For more exact evidence, geographic variations of body lengths and appendage sizes among areas were examined. Moreover, Freckleton et al. (2003) indicated that phylogenetic relationships may affect the results of one¡¦s study while variation of body size is discussed. Therefore, the phylogeographic variation among different areas was also examined in this study. The body lengths of N. coxingi in higher altitude (Fong-gang, 1700 m) were shorter than in lower altitude (Shan-ping 700 m). Body lengths of N. coxingi in Shan-ping were longer than other areas but Wu-shih-kang; and N. coxingi in Fong-gang were longer than those in Wu-tou Mountain; but no significant differences were found among other areas. No significant differences were found in appendage sizes but hind-foot length. Significant differences of the hind-foot length were only found between Shan-ping which had the longest hind-foot lengths in average and those in Wu-tou Mountain which had the shortest. No correlations were found between altitudes and the body length or appendage sizes of N. coxingi. The phylogenetic relationships based on D-loop region of N. coxingi were reconstructed by neighbor-joining, maximum parsimony and maximum-likelihood methods. An N. culturatus was used to be an outgroup. All three trees represented similar patterns. Although some individuals from neighborhood grouped together, some individuals from the same area represented distantly. Moreover, many branches represented in the root of the consensus trees because of the low bootstrap value. The results revealed the geographic variations did not correlated with their phylogenetic relationships and the heat conservation/ dissipation mechanism, which was the traditional explanation of Bergmann¡¦s rule, was not appropriate for N. coxingi, either.

Bergmann’s and Allen’s rule suggest that for the same species individuals found further north, tend to have larger body sizes and smaller appendages compared to individuals further south, respectively, due to constraints for thermal regulation. This has shown especially true for birds and mammals.  In this paper, I test to see if global warming has led to a change in morphology for birds, i.e. body weight and wing size. We use year as a proxy for temperature as global warming has on average lead to an increase in the earth’s surface temperature over the last century with most of the change occurring since the 1980’s.  To test the hypothesis, I gathered data of male, young of the year birds during autumn migration for a select number of species with different wintering strategies, i.e. resident to long-distance migration. This data came from two Swedish bird observatories where standardized wing and weight measurements have been collected since 1986, coincident with the observed climate warming. The results of this study show that during this period, changes in body mass and wing length did not support the hypothesis that global warming has had a broad impact on the morphology of birds. Given that these results contradict that of other studies, analysis from species across a much wider latitudinal breadth of Europe, including, additional species and different age and sex classes should be investigated.

No description available.