Bone size and its effect on body mass in Eothenomys miletus from the Hengduan Mountain region

Morphological characteristics are closely related to habitat characteristics; habitat differences drive morphological differentiation, resulting in intraspecific and interspecific differences. In the present study, it was shown that body mass and body length in Eothenomys miletus from five regions: (Dali (DL), Jianchuan (JC), Lijiang (LJ), Xianggelila (XGLL) and Deqin (DQ)) of Hengduan Mountain, showed differentiation in bone morphological indices. The length of the sternum in E. miletus in JC is smaller than that in XGLL, and the length of the lumbar vertebrae is smaller than that in XGLL and DQ. The length of other trunk bones and limb bones of E. miletus in DL, JC and LJ at low latitudes and high temperatures were longer than in XGLL and DQ at high latitudes and low temperatures. Principal component analysis associated XGLL and DQ populations and cluster analysis divided the populations from five regions into two categories. The increase in bone length and mass correlated with increased body mass in E. miletus. Change in bone length does not conform to Bergmann's Law, which was affected by altitude, average annual temperature and latitude. Moreover, food, terrain, and living habits may also affect bone morphology in E. miletus.

Automated summary

Morphological characteristics are influenced by habitat characteristics and show differences within and between species. This study found that Eothenomys miletus from different regions in the Hengduan Mountain have differentiation in bone morphological indices. The length of sternum and lumbar vertebrae showed differences between regions, and trunk and limb bones were longer in regions with low latitude and high temperature. Principal component analysis and cluster analysis divided the populations into two categories. The increase in bone length and mass correlated with body mass, but did not follow Bergmann's Law and was influenced by altitude, temperature, latitude, as well as food, terrain, and living habits.