DOI: 10.5061/dryad.vmcvdnd09
title: Within and between population comparisons suggest independently acting selection maintaining parallel clines in Scots pine (Pinus sylvestris)

description: Parallel clines in traits related to adaptation in a species can be due to
 independent selection on a pair of traits, or due to selection in one
 trait resulting in a parallel cline in a correlated trait. To distinguish
 between the mechanisms giving rise to parallel adaptive population
 divergence of multiple traits along an environmental gradient we need to
 study variation, correlations, and selective forces within individual
 populations along the gradient. In many tree species, budset timing forms
 a latitudinal cline, and parallel clinal variation is also found in other
 seedling traits, such as first year height and fall frost injury. In this
 study, we set up a common garden experiment with open pollinated progeny
 from natural populations of Scots pine (Pinus sylvestris), with one large
 sample from single population (500 families) and smaller samples from
 across a latitudinal gradient. Budset timing, first year height and
 induced fall frost injury were first measured in a greenhouse. The
 seedlings were then planted in the field, where survival and height were
 measured at the age of nine years as fitness proxies. We compared between
 and within population variation and genetic correlations of these three
 seedling traits, and estimated selection gradients at the family level in
 our main population, taking into account the potential effects of seed
 weight. Between population genetic correlations between seedling traits
 were high (0.76-0.95). Within population genetic correlations in the main
 population were lower (0.14-0.35), as in other populations (0.10-0.39).
 Within population, extensive adaptive variation persists in the seedling
 traits, in line with rather weak selection gradients, yet maintaining the
 clines. Although our sampling does not cover the whole cline equally, the
 results suggest that the individual clines in these traits are maintained
 by largely independently acting selection, which results in fewer
 constraints in adaptation under changing climate.
description: # Within and between population comparisons suggest independently acting
 selection maintaining parallel clines in Scots pine (<i>Pinus
 sylvestris</i>)
 [https://doi.org/10.5061/dryad.vmcvdnd09](https://doi.org/10.5061/dryad.vmcvdnd09) These files contain the data and R commands used to calculate family estimates, heritabilities, genetic correlations, and selection gradients in this publication. ## Description of the data and file structure File "data\_BST\_FYH\_field.txt" contains budset timing (BST) and first year height (FYH) measurements from a common garden experiment (greenhouse 2008) and field performance of the same seedlings (2017, plus inventories 2010, 2011). * family = family ID * origin = origin of the population sample * origin2 = in case of Punkaharju, subpopulation is indicated * ghblock2008 = block in greenhouse 2008 (1-6) * FYH = first year height (mm) * BST = budset timing (days) * fblock = block in field (1-10) * survival2010 = survival in 2010 inventory (0,1) * survival2011 = survival in 2011 inventory (0,1) * survival 2017 = survival in 2017 (0,1) * height2017 = height in 2017 (m) * (missing data = NA) File "data\_FFI.txt" contains fall frost injury (FFI) measurements from a common garden experiment (greenhouse 2010). * family = family ID * origin = origin of the population sample * origin2 = in case of Punkaharju, subpopulation is indicated * ghblock2010 = block in greenhouse 2010 (1-3) * FFI = fall frost injury, after cold treatment (score, 1-4) * (missing data = NA) File "data\_SW.txt" contains seed weight (from 200 seeds per seedlot) for each family. * family = family ID * FAM\_SW = seed weight (g) * (missing data = NA) ## ## Code/Software File "R\_commands.R" contains the R commands used to calculate family estimates, heritabilities, genetic correlations, and selection gradients in this publication.