Do elevational range size, abundance, and body size patterns mirror those documented for geographic ranges? A case study using Costa Rican rodents

Question: Do elevational range size, abundance, and body size patterns mirror those documented for geographic ranges? Data studied: Local and regional elevational ranges, abundances, and body sizes of Costa Rican rodents. Hypotheses: (1) Plotting elevational range against abundance will reveal a negative sloped, concave-upward relationship (hollow curve). (2) Elevational range sizes and geographic range sizes will be positively correlated. (3) Elevational range sizes will demonstrate a positive, linear trend with relative abundance. (4) Abundance will increase with rodent body size, and elevational range size will exhibit a triangular relationship with body size. (5) Abundances will peak near the elevational range midpoint. Conclusions: Elevational abundances followed hollow curves, but elevational range sizes did not. Elevational and geographic range sizes were unrelated. Species with larger ranges had higher abundances, although support was stronger regionally. Body size was not related either to elevational range size or to abundance at either scale. The highest abundances generally occurred somewhere in the middle of elevational ranges, but how close to the centre was highly variable.