Genotype variation in bark texture drives lichen community assembly across multiple environments

• Published in: Ecology (Durham) Vol. 96; no. 4; pp. 960 - 971
• Main Authors: Lamit, L. J, M. K. Lau, R. Reese Næsborg, T. Wojtowicz, T. G. Whitham, C. A. Gehring
• Format: Journal Article
• Language: English
• Published: United States Ecological Society of America 01.04.2015
• Subjects: bark; correlation; Ecosystem; epiphytes; genetic variation; Genotype; genotype-environment interaction; lichens; Lichens - classification; Lichens - physiology; Linear Models; ontogeny; Plant Bark - genetics; Plant Bark - physiology; Populus - genetics; Populus - physiology; Populus angustifolia; species diversity; texture; tree age; trees
• ISSN: 0012-9658; 1939-9170
• DOI: 10.1890/14-1007.1

A major goal of community genetics is to understand the influence of genetic variation within a species on ecological communities. Although well‐documented for some organisms, additional research is necessary to understand the relative and interactive effects of genotype and environment on biodiversity, identify mechanisms through which tree genotype influences communities, and connect this emerging field with existing themes in ecology. We employ an underutilized but ecologically significant group of organisms, epiphytic bark lichens, to understand the relative importance of Populus angustifolia (narrowleaf cottonwood) genotype and environment on associated organisms within the context of community assembly and host ontogeny. Several key findings emerged. (1) In a single common garden, tree genotype explained 18–33% and 51% of the variation in lichen community variables and rough bark cover, respectively. (2) Across replicated common gardens, tree genotype affected lichen species richness, total lichen cover, lichen species composition, and rough bark cover, whereas environment only influenced composition and there were no genotype by environment interactions. (3) Rough bark cover was positively correlated with total lichen cover and richness, and was associated with a shift in species composition; these patterns occurred with variation in rough bark cover among tree genotypes of the same age in common gardens and with increasing rough bark cover along a