Does biological intimacy shape ecological network structure? A test using a brood pollination mutualism on continental and oceanic islands
AuthorHembry, David H.
Raimundo, Rafael L. G.
Newman, Erica A.
Guimarães, Paulo R.
Gillespie, Rosemary G.
AffiliationUniv Arizona, Sch Nat Resources & Environm
Univ Arizona, Dept Ecol & Evolutionary Biol
Keywordsbiological intimacy hypothesis
MetadataShow full item record
CitationHembry DH, Raimundo RLG, Newman EA, et al. Does biological intimacy shape ecological network structure? A test using a brood pollination mutualism on continental and oceanic islands. J Anim Ecol. 2018;87:1160–1171. https://doi.org/10.1111/1365-2656.12841
JournalJOURNAL OF ANIMAL ECOLOGY
Rights© 2018 The Authors. Journal of Animal Ecology. © 2018 British Ecological Society.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
Abstract1. Biological intimacy-the degree of physical proximity or integration of partner taxa during their life cycles-is thought to promote the evolution of reciprocal specialization and modularity in the networks formed by co-occurring mutualistic species, but this hypothesis has rarely been tested. 2. Here, we test this "biological intimacy hypothesis" by comparing the network architecture of brood pollination mutualisms, in which specialized insects are simultaneously parasites (as larvae) and pollinators (as adults) of their host plants to that of other mutualisms which vary in their biological intimacy (including ant-myrmecophyte, ant-extrafloral nectary, plant-pollinator and plant-seed disperser assemblages). 3. We use a novel dataset sampled from leafflower trees (Phyllanthaceae: Phyllanthus s. l. [Glochidion]) and their pollinating leafflower moths (Lepidoptera: Epicephala) on three oceanic islands (French Polynesia) and compare it to equivalent published data from congeners on continental islands (Japan). We infer taxonomic diversity of leafflower moths using multilocus molecular phylogenetic analysis and examine several network structural properties: modularity (compartmentalization), reciprocality (symmetry) of specialization and algebraic connectivity. 4. We find that most leafflower-moth networks are reciprocally specialized and modular, as hypothesized. However, we also find that two oceanic island networks differ in their modularity and reciprocal specialization from the others, as a result of a supergeneralist moth taxon which interacts with nine of 10 available hosts. 5. Our results generally support the biological intimacy hypothesis, finding that leaf-flower-moth networks (usually) share a reciprocally specialized and modular structure with other intimate mutualisms such as ant-myrmecophyte symbioses, but unlike nonintimate mutualisms such as seed dispersal and nonintimate pollination. Additionally, we show that generalists-common in nonintimate mutualisms-can also evolve in intimate mutualisms, and that their effect is similar in both types of assemblages: once generalists emerge they reshape the network organization by connecting otherwise isolated modules.
Note12 month embargo; published online: 25 April 2018
VersionFinal accepted manuscript
SponsorsDivision of Environmental Biology ; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo [2009/54422-8, 2011/13054-6, 2014/21106-4]; Department of Integrative Biology, University of California Berkeley; Division of Graduate Education; Woodworth Loan in Entomology; Margaret C. Walker Fund; Moorea Biocode (Gordon and Betty Moore Foundation)