Analyses on body shape diversification among the Pecos Pupfish, Cyprinodon pecosensis populations in relation to interspecific interactions and environmental factors Abstract - During the 19th and 20th centuries, drastic anthropogenic alterations of the Pecos River (NM, USA) have greatly influenced the fish fauna within the drainage by fragmenting historically interconnected series of sinkholes and wetlands in the Bitter Lake National Wild Life Refuge (BLNWR). The Pecos pupfish (Cyprinodon pecosensis) might be the most impacted endemic small-bodied fish species. It was once abundant and relatively widespread; however, the large population has been disrupted and currently exists as distinct sub-populations persisting often in small numbers at a few isolated sites in New Mexico. Their habitats are severely fragmented that the connectivity among habitats can be extremely low. However, no research has been performed to consider the coordinated evolution of different species interacting in replicated communities. As part of a comprehensive multi-species evaluation, in this study, I analyze preliminary data collected to examine body shape variation in C. pecosensis from multiple major sites within and around the BLNWR. Geometric morphometric methods were used to examine the morphological divergence among natural C. pecosensis populations including: (1) between sexes (i.e. sexual dimorphism) within isolated sub-populations; (2) between allopatric and sympatric populations in similar environments; and (3) associated with environmental variation, independent of species interactions. The preliminary data and results suggest that body shape variation of C. pecosensis is substantial and in part related to variation in communities.

Authors: Xu, Qianna*, Collyer, Michael L.

Year: 2015 (xlvii)

Abstract

During the 19th and 20th centuries, drastic anthropogenic alterations of the Pecos River (NM, USA) have greatly influenced the fish fauna within the drainage by fragmenting historically interconnected series of sinkholes and wetlands in the Bitter Lake National Wild Life Refuge (BLNWR). The Pecos pupfish (Cyprinodon pecosensis) might be the most impacted endemic small-bodied fish species. It was once abundant and relatively widespread; however, the large population has been disrupted and currently exists as distinct sub-populations persisting often in small numbers at a few isolated sites in New Mexico. Their habitats are severely fragmented that the connectivity among habitats can be extremely low. However, no research has been performed to consider the coordinated evolution of different species interacting in replicated communities. As part of a comprehensive multi-species evaluation, in this study, I analyze preliminary data collected to examine body shape variation in C. pecosensis from multiple major sites within and around the BLNWR. Geometric morphometric methods were used to examine the morphological divergence among natural C. pecosensis populations including: (1) between sexes (i.e. sexual dimorphism) within isolated sub-populations; (2) between allopatric and sympatric populations in similar environments; and (3) associated with environmental variation, independent of species interactions. The preliminary data and results suggest that body shape variation of C. pecosensis is substantial and in part related to variation in communities.