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Data from: Consistent scaling of inbreeding depression in space and time in a house sparrow metapopulation


Niskanen, Alina K. et al. (2020), Data from: Consistent scaling of inbreeding depression in space and time in a house sparrow metapopulation, Dryad, Dataset,


Inbreeding may increase the extinction risk of small populations. Yet, studies using modern genomic tools to investigate inbreeding depression in nature have been limited to single populations, and little is known about the dynamics of inbreeding depression in subdivided populations over time. Natural populations often experience different environmental conditions and differ in demographic history and genetic composition; characteristics that can affect the severity of inbreeding depression. We utilised extensive long-term data on more than 3100 individuals from eight islands in an insular house sparrow metapopulation to examine the generality of inbreeding effects. Using genomic estimates of realised inbreeding, we discovered that inbred individuals had lower survival probabilities and produced fewer recruiting offspring than non-inbred individuals. Inbreeding depression, measured as the decline in fitness related traits per unit inbreeding, did not vary appreciably among populations or with time. As a consequence, populations with more resident inbreeding (due to their demographic history) paid a higher total fitness cost, evidenced by a larger variance in fitness explained by inbreeding within these populations. Our results are in contrast to the idea that effects of inbreeding generally depend on ecological factors and genetic differences among populations, and expand the understanding of inbreeding depression in natural subdivided populations.


Data has been collected from house sparrows on eight islands in the Helgeland archipelago in Norway. Datasets include SNP-genotypes for pedigree construction and pedigree. SNP-genotypes, fitness estimates and morphological data are available on request from and will become public in June 2022. Scripts include estimation of genomic and pedigree inbreeding coefficients and conducting analyses on the effects of inbreeding on fitness and morphological traits.

Usage Notes

Description of the data and scripts are given in the Dryad_readme file.


Academy of Finland, Award: 295204

Suomen Kulttuurirahasto

Oskar Huttunen Foundation

Norges Forskningsråd, Award: 221956

Norges Forskningsråd, Award: 214553

Norges Forskningsråd, Award: 274930

Norges Forskningsråd, Award: 302619

Norges Forskningsråd, Award: 223257

Oskar Huttunen Foundation