Several candidate size metrics explain vital rates across multiple populations throughout a widespread species' range

Individual plant size often determines the vital rates of growth, survival, and reproduction. However, size can be measured in several ways (e.g., height, biomass, leaf length). There is no consensus on the best size metric for modelling vital rates in plants. Demographic datasets are expanding in geographic extent, leading to choices about how to represent size for the same species in multiple ecological contexts. If the choice of size variable varies among locations, inter-population comparative demography increases in complexity. Here, we present a framework to perform size metric selection in large-scale demographic studies. We highlight potential pitfalls and suggest methods applicable to diverse study organisms. We assessed the performance of five different size metrics for the perennial herb Plantago lanceolata across 55 populations on three continents within its native and non-native ranges, using the spatially replicated demographic dataset PlantPopNet. We compared the performa..., PlantPopNet (www.plantpopnet.com) collaborators collect demographic information on 65 naturally occurring populations of P. lanceolata across three continents. The present study included 55 populations that had at least two consecutive yearly censuses, presented here. Each population consists of an initial 100 individuals marked in naturally occurring populations and re-visited yearly at the peak of the flowering season. New recruits within the original plots were recorded and followed in subsequent years. The number of rosettes, number of leaves per rosette, length of the longest leaf, and width of the longest leaf for each rosette, flowering status (flowered, not flowered), reproductive output, and survival or death of each individual were recorded at each annual census. For further information on the PlantPopNet protocol, see Buckley et al. (2019). This data is presented as it was used to perform a study on a subset of the plantpopnet data. For said study, we used the first transitio..., , # Several candidate size metrics explain vital rates across multiple populations throughout a widespread species' range

[https://doi.org/10.5061/dryad.mw6m9067c](https://doi.org/10.5061/dryad.mw6m9067c)

## Description of the data and file structure

Code and analysis are described in detail in the main text and supplementary materials of the associated Journal of Ecology paper. If you have any questions regarding the R code files you may contact Maude Baudraz at [[e-mail]](mailto:[e-mail]) or [[e-mail]](mailto:[e-mail])

Data provided herein represent a derived version from the PlantPopNet dataset, a Spatially Distributed Model System for Population Ecology. They represent demographic information for all individuals in over 55 populations of the perennial plant *Plantago lanceolata* spread throughout three continents. The data published contains size, growth, reproduction, and survival information. More information about the PlantPopNet netw...,