DOI: 10.5061/dryad.83g9k
title: Data from: Plasticity in plant functional traits is shaped by variability in neighbourhood species composition

description: Plant functional traits can vary widely as a result of phenotypic
 plasticity to abiotic conditions. Trait variation may also reflect
 responses to the identity of neighbours, although not all species are
 equally responsive to their biotic surroundings. We hypothesized that
 responses to neighbours are shaped by spatial community patterns and
 resulting variability in neighbour composition. More precisely, we tested
 the theoretical prediction that plasticity is most likely to evolve if
 alternative environments (in this case, different neighbour species) are
 common and encountered at similar frequencies. We estimated the
 frequencies of encountering different neighbour species in the field for
 27 grassland species and measured the aboveground morphological responses
 of each species to conspecific vs heterospecific neighbours in a common
 garden. Responses to neighbour identity were dependent on how frequently
 the experimental neighbours were encountered by the focal species in their
 home community, with the greatest plasticity observed in species that
 encountered both neighbours (conspecific and heterospecific) with high and
 even frequency. Biotic interactions with neighbouring species can impose
 selection on plasticity in functional traits, which may feed back through
 trait divergence and niche differentiation to influence species
 coexistence and community structure.
description: Functional trait data
 for 27 temperate grassland speciesTraits were measured on
 plants grown in a common garden in Tartu, Estonia (58°22´N, 26°41´E) using
 seeds collected from seven grasslands that differed in species richness
 and composition, soil fertility, pH, and management history (seed origin
 coordinates supplied). Individual plants of each focal species were
 subjected to treatments that manipulated a) neighbour identity (surrounded
 by either conspecifics or heterospecifics), and b) neighbour density (0,
 1, 2, 3, 4, 6 or 8 neighbours). Each neighbour identity by density
 combination was replicated twice. In the heterospecific treatment, each
 focal species was grown together with a species that it frequently
 encountered in the field as its nearest neighbour. Five aboveground traits
 and total aboveground dry mass of focal and neighbour plants were
 recorded. The maximum vegetative height of the focal plants was measured
 as the highest point reached by stem leaves (or rosette leaves in the
 absence of a leafed stem). Leaf water content was calculated by dividing
 the difference between fresh and dry mass by the fresh mass of two newly
 produced but fully expanded leaf blades (four leaves for Carex
 ornithopoda, Juncus gerardii, Veronica chamaedrys; five leaves for
 Antennaria dioica; ten leaves for Lotus corniculatus; 25 leaves for Galium
 verum). Specific leaf area (SLA), was calculated as the ratio of leaf area
 and leaf dry mass of leaves used for water content measurements. The dry
 mass of the supportive structures was found by summing the dry mass of
 stems (including stolons), leaf petioles and leaf sheaths (in the case of
 graminoids). All above-ground parts of each focal plant and its neighbours
 were oven-dried at 70C for 48 h and weighed separately as necessary for
 calculations.Abakumova_etal_NEWPHY2016_morphology_data.txt