In most animal species, dispersing individuals possess phenotypic attributes that mitigate the costs of colonization and/or increase settlement success in new areas (‘dispersal syndromes’). This phenotypic integration likely affects population dynamics and the direction of selection, but data are lacking for natural populations. Using an approach that combines population dynamics, quantitative genetics and phenotypic selection analyses, we reveal the existence of dispersal syndromes in a pied flycatcher (Ficedula hypoleuca) population in The Netherlands: immigrants were larger, tended to have darker plumage, bred earlier and produced larger clutches than local recruits, and some of these traits were genetically correlated. Over time, the phenotypic profile of the population gradually changed: each generation advanced arrival and breeding and exhibited longer wings as the result of direct and indirect selection on these correlated traits. Although phenotypic attributes of immigrants were favored by selection during the early phase of colonization, observed phenotypic changes were similar for immigrants and local recruits. We propose that immigrants facilitated initial population establishment but that temporal changes likely resulted from climate change-induced large-scale selection. This study highlights that newly established populations are of non-random composition and that phenotypic architecture affects evolutionary population trajectories.  

Data sets were collected in a wild pied flycatcher population in Drenthe in the Netherlands from 2007 until 2018. Three datasets have been used in this manuscript:

1. phenotypic data on population change (life-history and morphological traits measured in each year) = "data population change"

2. phenotypic selection dataset (relative fitness measurements and standardized phenotypic traits measured in each year) = "data phenotypic selection

3. quantitative genetics dataset (data + pedigree file) = "pedigree" & "data quantitative genetics"

Missing values are indicated as NA, and explanations of headings are provided in the tab 'codes' of the Excel files and in the "read me first" file.

The data file can be opened with excel and/or R software (R codes are also provided).