High variability of dung beetle diversity patterns at four mountains of the Trans-Mexican Volcanic Belt

PeerJ

article

Alfonsina Arriaga-Jiménez¹  Matthias Rös³  Gonzalo Halffter⁴ 

[1] CIIDIR Oaxaca, Instituto Politécnico Nacional;Laboratoire de Zoogéographie, UMR 5175 CEFE, Université Paul Valéry;CONACYT, CIIDIR Oaxaca, Instituto Politécnico Nacional;Red de Etoecologia, Instituto de Ecologia

关键词: Mexican transition zone;    Compositional similarity;    Species distribution patterns;    q-Diversity;    Horizontal colonization;    Environmental instability;    Archipelago reserves;   

DOI  :  10.7717/peerj.4468

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Insect diversity patterns of high mountain ecosystems remain poorly studied in the tropics. Sampling dung beetles of the subfamilies Aphodiinae, Scarabaeinae, and Geotrupinae was carried out at four volcanoes in the Trans-Mexican Volcanic Belt (TMVB) in the Mexican transition zone at 2,700 and 3,400 MASL, and on the windward and leeward sides. Sampling units represented a forest–shrubland–pasture (FSP) mosaic typical of this mountain region. A total of 3,430 individuals of 29 dung beetle species were collected. Diversity, abundance and compositional similarity (CS) displayed a high variability at all scales; elevation, cardinal direction, or FSP mosaics did not show any patterns of higher or lower values of those measures. The four mountains were different regarding dispersion patterns and taxonomic groups, both for species and individuals. Onthophagus chevrolati dominated all four mountains with an overall relative abundance of 63%. CS was not related to distance among mountains, but when O. chevrolati10% of all species sampled). These discoveries may indicate that speciation rate is high among these volcanoes—a hypothesis that is also supported by the elevated number of collected species with a restricted montane distribution. Dispersion is an important factor in driving species composition, although naturally limited between high mountains; horizontal colonization events at different time scales may best explain the observed species composition in the TMVB, complemented by vertical colonization events to a lesser extent. Environmental instability may be the main factor causing the high variability of diversity and abundance patterns found during sampling. Together, we interpret these results as indicating that species richness and composition in the high mountains of the TMVB may be driven by biogeographical history while variability in diversity is determined by ecological factors. We argue that current conservation strategies do not focus sufficiently on protecting high mountain fauna, and that there is a need for developing and applying new conservation concepts that take into account the high spatial and temporal variability of this system.

【 授权许可】

CC BY