Network reorganization and breakdown of an ant-plant protection mutualism with elavation

0474049 - BC 2018 RIV GB eng J - Journal Article
Plowman, Nichola S. - Hood, A. S. C. - Moses, J. - Redmond, Conor - Novotný, Vojtěch - Klimeš, Petr - Fayle, Tom Maurice
Network reorganization and breakdown of an ant-plant protection mutualism with elavation.
Proceedings of the Royal Society B-Biological Sciences. Roč. 284, č. 1850 (2017), č. článku 20162564. ISSN 0962-8452. E-ISSN 1471-2954
R&D Projects: GA ČR GA13-10486S
Grant - others:GA JU(CZ) 156/2013/P
Institutional support: RVO:60077344
Keywords : altitudinal gradients * biotic defence * global change
OECD category: Ecology
Impact factor: 4.847, year: 2017
http://rspb.royalsocietypublishing.org/content/royprsb/284/1850/20162564.full.pdf

Both the abiotic environment and the composition of animal and plant communities change with elevation. For mutualistic species, these changes are expected to result in altered partner availability, and shifts in context-dependent benefits for partners. To test these predictions, we assessed the network structure of terrestrial ant-plant mutualists and how the benefits to plants of ant inhabitation changed with elevation in tropical forest in Papua New Guinea. At higher elevations, ant-plants were rarer, species richness of both ants and plants decreased, and the average ant or plant species interacted with fewer partners. However, networks became increasingly connected and less specialized, more than could be accounted for by reductions in ant-plant abundance. On the most common ant-plant, ants recruited less and spent less time attacking a surrogate herbivore at higher elevations, and herbivory damage increased. These changes were driven by turnover of ant species rather than by within-species shifts in protective behaviour. We speculate that reduced partner availability at higher elevations results in less specialized networks, while lower temperatures mean that even for ant-inhabited plants, benefits are reduced. Under increased abiotic stress, mutualistic networks can break down, owing to a combination of lower population sizes, and a reduction in context-dependent mutualistic benefits.
Permanent Link: http://hdl.handle.net/11104/0271188