Costly neighbours: Heterospecific competitive interactions increase metabolic rates in dominant species

0476142 - ÚBO 2018 RIV GB eng J - Journal Article
Janča, M. - Gvoždík, Lumír
Costly neighbours: Heterospecific competitive interactions increase metabolic rates in dominant species.
Scientific Reports. Roč. 7, č. 5177 (2017), č. článku 5177. ISSN 2045-2322. E-ISSN 2045-2322
R&D Projects: GA ČR(CZ) GA15-07140S
Institutional support: RVO:68081766
Keywords : interference competition * intraspecific variation * terrestrial salamander * energy metabolism * natural selection * newts
OECD category: Zoology
Impact factor: 4.122, year: 2017

The energy costs of self-maintenance (standard metabolic rate, SMR) vary substantially among individuals within a population. Despite the importance of SMR for understanding life history strategies, ecological sources of SMR variation remain only partially understood. Stress-mediated increases in SMR are common in subordinate individuals within a population, while the direction and magnitude of the SMR shift induced by interspecific competitive interactions is largely unknown. Using laboratory experiments, we examined the influence of con- and heterospecific pairing on SMR, spontaneous activity, and somatic growth rates in the sympatrically living juvenile newts Ichthyosaura alpestris and Lissotriton vulgaris. The experimental pairing had little influence on SMR and growth rates in the smaller species, L. vulgaris. Individuals exposed to con- and heterospecific interactions were more active than individually reared newts. In the larger species, I. alpestris, heterospecific interactions induced SMR to increase beyond values of individually reared counterparts. Individuals from heterospecific pairs and larger conspecifics grew faster than did newts in other groups. The plastic shift in SMR was independent of the variation in growth rate and activity level. These results reveal a new source of individual SMR variation and potential costs of co-occurrence in ecologically similar taxa.
Permanent Link: http://hdl.handle.net/11104/0272672