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Plant traits – the morphological, anatomical, physiological, biochemical and phenological characteristics of plants and their organs – determine how primary producers respond to environmental factors, affect other trophic levels, influence ecosystem processes and services and provide a link from species richness to ecosystem functional diversity. Trait data thus represent the raw material for a wide range of research from evolutionary biology, community and functional ecology to biogeography. Here we present the global database initiative named TRY, which has united a wide range of the plant trait research community worldwide and gained an unprecedented buy-in of trait data: so far 93 trait databases have been contributed. The data repository currently contains almost three million trait entries for 69 000 out of the world’s 300 000 plant species, with a focus on 52 groups of traits characterizing the vegetative and regeneration stages of the plant life cycle, including growth, dispersal, establishment and persistence. A first data analysis shows that most plant traits are approximately log-normally distributed, with widely differing ranges of variation across traits. Most trait variation is between species (interspecific), but significant intraspecific variation is also documented, up to 40% of the overall variation. Plant functional types (PFTs), as commonly used in vegetation models, capture a substantial fraction of the observed variation – but for several traits most variation occurs within PFTs, up to 75% of the overall variation. In the context of vegetation models these traits would better be represented by state variables rather than fixed parameter values. The improved availability of plant trait data in the unified global database is expected to support a paradigm shift from species to trait-based ecology, offer new opportunities for synthetic plant trait research and enable a more realistic and empirically grounded representation of terrestrial vegetation in Earth system models.

Plant traits – the morphological, anatomical, physiological, biochemical and phenological characteristics of plants and their organs – determine how primary producers respond to environmental factors, affect other trophic levels, influence ecosystem processes and services and provide a link from species richness to ecosystem functional diversity. Trait data thus represent the raw material for a wide range of research from evolutionary biology, community and functional ecology to biogeography. Here we present the global database initiative named TRY, which has united a wide range of the plant trait research community worldwide and gained an unprecedented buy-in of trait data: so far 93 trait databases have been contributed. The data repository currently contains almost three million trait entries for 69 000 out of the world's 300 000 plant species, with a focus on 52 groups of traits characterizing the vegetative and regeneration stages of the plant life cycle, including growth, dispersal, establishment and persistence. A first data analysis shows that most plant traits are approximately log-normally distributed, with widely differing ranges of variation across traits. Most trait variation is between species (interspecific), but significant intraspecific variation is also documented, up to 40% of the overall variation. Plant functional types (PFTs), as commonly used in vegetation models, capture a substantial fraction of the observed variation – but for several traits most variation occurs within PFTs, up to 75% of the overall variation. In the context of vegetation models these traits would better be represented by state variables rather than fixed parameter values. The improved availability of plant trait data in the unified global database is expected to support a paradigm shift from species to trait-based ecology, offer new opportunities for synthetic plant trait research and enable a more realistic and empirically grounded representation of terrestrial vegetation in Earth system models.

Rapid recent developments in DNA sequencing and genetic marker technologies call for the establishment of cost-effective, automated phenotyping assays for evolutionary biology and systematics, so that the effects of DNA polymorphisms and epigenetic changes on the phenotype can be evaluated. We discuss the use of digital image-based morphometrics in evolutionary biology and systematics with special emphasis on studies of taxa with porous genomes, i.e., taxa that do not conform to the traditional view of whole-genome isolation between species. We outline the phenomenon of the 'phenotypic mosaic' in taxa with porous genomes using well-documented examples from the literature and describe three important challenges arising for taxonomists: (1) character conflict in phylogenetic studies, (2) biased sampling of traits in morphological studies, and (3) cryptic ecological speciation. We demonstrate the use of geometric morphometrics using a combined molecular and morphometric dataset from an interspecific hybrid zone between two divergent Eurasian species of Populus, P. alba (white poplar) and P. tremula (European aspen). Elliptic Fourier analysis (EFA)-based morphometric data were collected for 527 leaf specimens from 84 trees with known genomic composition as determined by a set of 30 nuclear DNA microsatellites. In addition, to demonstrate the ease of scoring functionally relevant phenotypes via digital image analysis, quantitative differences in leaf reflectance were examined and their structural basis determined using scanning electron microscopy (SEM). The EFA results indicate a heritable inter-individual component for symmetric aspects and an important intra-individual component for asymmetric aspects of variation in leaf outlines. Symmetric traits displayed a striking variety of phenotypes in hybrids compared to their parental species, consistent with the notion of the phenotypic mosaic. Linear discriminant analysis of these morphometric traits revealed (1) clear differentiation between parental species and (2) divergence between recombinant hybrids and their sympatric backcross parent P. alba, mediated primarily by two P. tremula-like and two transgressive traits. Our results demonstrate the usefulness of geometric morphometrics to interrogate multiple independent phenotypic characters and detect individual traits affected by introgression and divergence in taxa with porous genomes. Digital image-based morphometrics holds great promise for large-scale studies of relationships between DNA polymorphism and phenotypes in evolutionary biology.

Arthur Francis George Kerr's life is reviewed and related to a previously published account. Kerr's collecting activity is analysed using an expanded version of the Thai Biogeography Group's database of collections. 8,666 of the total 48,970 collections are Kerr's and 3,178 are those of his colleagues and friends. Therefore, the total number of collections made by Kerr and his acquaintances is likely to be larger and more diverse than previously believed. Mapping of these data using GIS show that Kerr's collecting activities focussed on particular regions of Thailand at particular times. Also large areas of the country remained unexplored by Kerr and his acquaintances: a pattern that, to some extent, persists to this day. The large, but dispersed, archive of Kerr's photographs, maps, living collections and correspondence indicate that he was a skilled photographer (taking at least 3,000 images), cartographer (producing many hand-drawn maps) and exceptionally acute, accurate and detailed observer (fi lling numerous notebooks and leaving other records). It is clear that digitising these collections to form an on-line dedicated website is highly desirable to further progress on the fl ora of Thailand and surrounding countries and would form an unique record of the social history of early 20thC Thailand.