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Biology subjects

Bastias, C. C.

Publications and source records attributed to Bastias, C. C..

3 recordsLinked to original sources

Adaptation to climate in the native and introduced ranges of a cosmopolitan plant

Climate change and the global spread of non-native species are two of the most significant threats to biodiversity and ecosystem function. Both these phenomena subject populations to novel conditions, either in space (species introductions) or in time (climate change), yet the role of adaptation in how populations respond to these rapid environmental shifts is poorly understood. We conducted a large-scale trans-continental common garden experiment using white clover (Trifolium repens, Fabaceae) to test whether adaptive evolution to spatiotemporal variation in climate could contribute to the ecological success of one of the most widespread plant species in the world. Individuals from 96 populations of Trifolium repens (white clover) from both its native (Europe) and introduced (North America) ranges were planted into four experimental common gardens located in northern (Uppsala, Sweden) and southern (Montpellier, France) Europe, and northern (Mississauga, Canada) and southern (Lafayette, USA) North America. We recorded plant sexual and clonal fitness in each common garden and assessed whether the strength of local adaptation differed between the native and introduced ranges and whether populations are rapidly adapting to climate change. Results show that local adaptation was only evident when populations were transplanted into common gardens located in the same range (native or introduced) from which they originated and was driven by stronger selection (due to climatic factors rather than herbivory) at lower latitudes in both ranges. Our results indicate rapid local adaptation across a large latitudinal gradient in introduced T. repens populations, along with an associated adaptation cost when transplanted back into the native range. We also find evidence of an adaptation lag in the northern common garden in the introduced range, with plants from historically warmer climates exhibiting the greatest fitness. These findings support two major conclusions: 1) white clover can rapidly adapt to spatial variation in climate in its introduced range as well as the native range, and 2) despite rapid adaptation to novel environments, introduced white clover populations are not keeping pace with rapid climate change. Overall, our results provide insight into the role of adaptation in facilitating the ecological success of non-native species in a rapidly changing world. Open Research StatementData are provided for peer review. All data involved in this study is available on the GitHub page for LJA (https://github.com/ljalbano/transcontinental_common_garden).

evolutionary biology↗

Ecological and genetic trade-offs drive Arabidopsis thaliana range expansion in Europe

How trade-offs between traits constrain adaptation to contrasted environments is critical to understand the distribution range of a given species. In Arabidopsis thaliana, genetic analyses recently revealed that a group of genotypes successfully recolonized Europe from its center after the last glaciation, outcompeting older lineages and leaving them only at the distribution margins, where environmental conditions are more stressing. However, whether trade-offs between traits related to dispersal, competition, and stress tolerance explain the success and persistence of different lineages across the species geographic range remains an open question. Here, we compared the genetic and phenotypic differentiation between 72 ecotypes originating from three geographical groups in Europe (North, South and Center). We measured key traits related to fecundity, dispersal ability, competition tolerance, and stress tolerance, and used genomic data to infer the effect of selection on these traits. We showed that a trade-off between plant fecundity and seed mass constrains the diversification of A. thaliana in Europe. In particular, the success of the cosmopolitan genotypes that recolonized Europe can be explained by their higher dispersal ability at the expense of their competitive ability and stress tolerance. Inversely, peripheral ecotypes exhibited the opposite trait syndrome: high competition and stress tolerance but low dispersal ability. Moreover, peripheral genotypes tend to differentiate from central ones at genes involved in dispersal and competitive traits such as seed mass. Combining ecological and genomic approaches, our study demonstrated the role of key ecological trade-offs as evolutionary drivers of the distribution of plant populations along a geographic gradient. SignificanceAcross geographic gradients, differential adaptive phenotypes among populations can reduce the risk of local extinctions and favor niche dynamics. However, a phenotypic advantage often comes at a cost. For instance, the competition-colonization trade-off is proposed as an important driver of plant interspecific diversity, but its role for local adaptation at the intraspecific level is still unclear. Using the broadly-distributed species Arabidopsis thaliana, we evaluate how ecological trade-offs have shaped the demography and evolution of central and peripheral populations in its native geographic gradient. Our study demonstrates that the competition-colonization trade-off is responsible of the spatially-structured phenotypic variation of A. thaliana across its geographical range. Our study highlights seed mass as a key trait for plant adaptation across environmental conditions.

ecology↗

Linking functional traits with tree growth and forest productivity in Quercus ilex forests along a climatic gradient

Plant functional traits are highly adaptable to changes in climatic factors and nutrient availability. However, the intraspecific plant response to abiotic factors and the overall effect on plant growth and productivity is still under debate. We studied forest productivity for 30 Quercus ilex subsp ballota forests in Spain along a broad climatic gradient of aridity (mean annual precipitation from 321 to 1582 mm). We used linear mixed models to quantify the effect of climatic and edaphic factors on functional traits, and to study the effect of functional traits and abiotic factors on the relative growth rate (RGR) of adult trees. Then we used piecewise structural equation models (SEMs) to determine the causal effect of intrinsic and extrinsic factors on forest productivity. Our results showed that forest productivity is positively affected by forest biomass and RGR, which are mainly affected by functional traits and tree biomass, respectively. In conclusion, intraspecific variability of functional traits have a significant effect on plant biomass and growth, which ultimately explain forest productivity in Quercus ilex.

ecology↗