TY - JOUR

T1 - Uncovering the spatio-temporal drivers of species trait variances

T2 - a case study of Magnoliaceae in China

AU - Liu, Hui

AU - Lundgren, Marjorie R.

AU - Freckleton, Robert P.

AU - Xu, Qiuyuan

AU - Ye, Qing

PY - 2016/6

Y1 - 2016/6

N2 - Aim Analyses of the relationships between evolutionary history, environmental constraints and associated trait variances can reveal how species distributions were shaped. Phylogenetic comparative models can be used to disentangle the relative roles of spatial and phylogenetic factors in explaining trait variances. Here, we analyse variances in plant traits and environmental variables of the widely distributed and early diverging Magnoliaceae within a phylogeographical context to test whether species distributions have been limited more by evolutionary or spatial constraints in this family.Location China.Methods The phylogenetic relatedness and geographical distributions of 183 Magnoliaceae species in China were analysed for phylogenetic clustering or over-dispersion. The phylogenetic signals of 15 plant traits and 12 environmental variables were determined, and the relative contributions of phylogeny and space to each quantitative trait were distinguished using four comparative models.Results Species richness gradually decreased from south to north, with phylogenetic clustering along the southern coast, and in northern and central China. Strong phylogenetic signals were found in leaf form, flowering sequence, diameter at breast height, leaf length and width, mean and minimum mean annual temperature, and minimum mean annual precipitation. Variances of plant diameter, length and width of leaves and tepals, and fruit length were strongly associated with phylogenetic relatedness. In contrast, variances of plant height, flowering and fruiting time, and all of the 12 environmental variables (mean, minimum, maximum and range of altitude, temperature and precipitation) were associated with both spatial proximity and phylogenetic distance between species.Main conclusions Phylogenetic niche conservatism was identified in most of the studied plant traits across the Magnoliaceae. In contrast, environmental variables showed weak phylogenetic signals, but strong spatial signals. These results suggest that the present tropical-temperate distributional pattern of the Magnoliaceae is driven by the ecophysiological adaptation of plant traits under both geographical separation and environmental constraints.

AB - Aim Analyses of the relationships between evolutionary history, environmental constraints and associated trait variances can reveal how species distributions were shaped. Phylogenetic comparative models can be used to disentangle the relative roles of spatial and phylogenetic factors in explaining trait variances. Here, we analyse variances in plant traits and environmental variables of the widely distributed and early diverging Magnoliaceae within a phylogeographical context to test whether species distributions have been limited more by evolutionary or spatial constraints in this family.Location China.Methods The phylogenetic relatedness and geographical distributions of 183 Magnoliaceae species in China were analysed for phylogenetic clustering or over-dispersion. The phylogenetic signals of 15 plant traits and 12 environmental variables were determined, and the relative contributions of phylogeny and space to each quantitative trait were distinguished using four comparative models.Results Species richness gradually decreased from south to north, with phylogenetic clustering along the southern coast, and in northern and central China. Strong phylogenetic signals were found in leaf form, flowering sequence, diameter at breast height, leaf length and width, mean and minimum mean annual temperature, and minimum mean annual precipitation. Variances of plant diameter, length and width of leaves and tepals, and fruit length were strongly associated with phylogenetic relatedness. In contrast, variances of plant height, flowering and fruiting time, and all of the 12 environmental variables (mean, minimum, maximum and range of altitude, temperature and precipitation) were associated with both spatial proximity and phylogenetic distance between species.Main conclusions Phylogenetic niche conservatism was identified in most of the studied plant traits across the Magnoliaceae. In contrast, environmental variables showed weak phylogenetic signals, but strong spatial signals. These results suggest that the present tropical-temperate distributional pattern of the Magnoliaceae is driven by the ecophysiological adaptation of plant traits under both geographical separation and environmental constraints.

KW - comparative methods

KW - divergent evolution

KW - geography

KW - Magnoliaceae

KW - net relatedness index

KW - phenology

KW - phylogenetic niche conservatism

KW - phylogenetic signal

KW - spatial signal

KW - PHYLOGENETIC NICHE CONSERVATISM

KW - COMMUNITY ECOLOGY

KW - FUNCTIONAL TRAIT

KW - EVOLUTION

KW - CONVERGENCE

KW - ADAPTATION

KW - BIOLOGY

KW - SIGNAL

KW - PLANTS

KW - SCALE

U2 - 10.1111/jbi.12707

DO - 10.1111/jbi.12707

M3 - Journal article

VL - 43

SP - 1179

EP - 1191

JO - Journal of Biogeography

JF - Journal of Biogeography

SN - 0305-0270

IS - 6

ER -