Contrasting forms of competition set elevational range limits of species

• Published in: Ecology letters Vol. 22; no. 10; pp. 1668 - 1679
• Main Authors: Chan, Shih‐Fan, Shih, Wei‐Kai, Chang, An‐Yu, Shen, Sheng‐Feng, Chen, I‐Ching, Novotny, Vojtech
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01.10.2019
• Subjects: Abiotic factors; Altitude; Animals; Beetles; Benign; Biotic factors; Breeding; Breeding performance; China; Climate; Coleoptera; Competition; Competitive Behavior; Elevation; experimental macroecology; exploitative competition; harsh or benign climate; interference competition; Models, Statistical; Nicrophorus nepalensis; Population Density; Proximate causes; Species; Temperature; China; exploitative competition; interference competition; Nicrophorus nepalensis; experimental macroecology; harsh or benign climate; Breeding performance
• ISSN: 1461-023X; 1461-0248
• DOI: 10.1111/ele.13342

How abiotic and biotic factors constrain distribution limits at the harsh and benign edges of species ranges is hotly debated, partly because macroecological experiments testing the proximate causes of distribution limits are scarce. It has long been recognized – at least since Darwin’s On the Origin of Species – that a harsh climate strengthens competition and thus sets species range limits. Using thorough field manipulations along a large elevation gradient, we show the mechanisms by which temperature determines competition type, resulting in a transition from interference to exploitative competition from the lower to the upper elevation limits in burying beetles (Nicrophorus nepalensis). This transition is an example of Darwin’s classic hypothesis that benign climates favor direct competition for highly accessible resources while harsh climates result in competition through resources of high rivalry. We propose that identifying the properties of these key resources will provide a more predictive framework to understand the interplay between biotic and abiotic factors in determining geographic range limits.