Phylogenetic community spatial structure has been increasingly used to make inferences about community assembly processes.

In order to ensure appropriate interpretation of phylogenetic information, it is necessary to know more about how phylogenetic structure in space and traits relates to ecologically significant characteristics such as niche preferences. 

Researchers from Xishuangbanna Tropical Botanical Garden (XTBG) of the Chinese Academy of Sciences investigated phylogenetic signals in known environmental niches of 64 common species of seedlings and large trees in the Xishuangbanna 20-ha tropical forest dynamics plot.

They used phylogenetic comparative analysis to quantify phylogenetic signals and determine whether local environmental niches (based on topographic and soil factors) relate to phylogenies in meaningful and consistent ways across life stages. 

The statistical analyses gave consistent results for the extent of phylogenetic signals within environmental niches.

The results demonstrated a clear lack of phylogenetic signals within environmental niches at the local scale.

Furthermore, the results indicated lability in local-scale environmental niches both in seedlings and large trees, with closely related species occupying niches that are no more similar than expected by random chance. 

Viewing the findings in the context of previous studies that have found significant phylogenetic signals in functional traits in the same plot, inferences regarding community assembly drawn from phylogenetic dispersion patterns may be unreliable.

Phylogenetic signals in traits might not be a reliable guide to niche preferences or, therefore, to community assembly processes in some ecosystems, like the Xishuangbanna 20-ha forest dynamics plot. 

The study entitled “Lack of phylogenetic signals within environmental niches of tropical tree species across life stages” has been published in Scientific Reports.