Geographical variation in skull morphology and suitable habitat changes
of the Orientallactaga sibirica under environmental drivers in China
Abstract
The O. sibirica (Orientallactaga sibirica), a member of the family
Dipodidae, is widely distributed across Central Asia and plays a
significant role in grassland ecosystems. While substantial ecological
data on this species exists in China, research on intraspecific cranial
variation is limited, and no extensive surveys have been conducted
within its Chinese distribution range. This study aims to address this
gap by capturing O. sibirica specimens from various geographical regions
within China, conducting geometric morphometric analyses on their
skulls, and examining the influence of current climatic conditions.
Additionally, we predict changes in the suitable habitat areas for O.
sibirica in China under future climate scenarios. Our results indicate
that the major cranial variations in O. sibirica occur in the nasal,
parietal, maxilla near the nasal end, zygomatic arch, and preorbital
bridge. These features result in skulls from northeastern China
clustering furthest from those in the Qinghai-Tibet Plateau. Skull size
is primarily influenced by precipitation, whereas skull shape is
affected by longitude, altitude, and temperature. Under future global
changes, the suitable habitat for O. sibirica is likely to shrink, with
the distribution centroid shifting towards higher latitudes in a
northeasterly direction. Our analysis reveals that the cranial
morphology of O. sibirica exhibits divergent adaptation across different
geographical regions, particularly in the Qinghai-Tibet region, which we
suggest should be designated as a new subspecies. Concurrently, future
global changes are anticipated to alter the extent of suitable habitats
in China, necessitating proactive measures to prevent potential rodent
outbreaks.