DOI: 10.5061/dryad.2jj06
title: Data from: Immigrant reproductive dysfunction facilitates ecological speciation

description: The distributions of species are not only determined by where they can
 survive – they must also be able to reproduce. Although immigrant
 inviability is a well-established concept, the fact that immigrants also
 need to be able to effectively reproduce in foreign environments has not
 been fully appreciated in the study of adaptive divergence and speciation.
 Fertilization and reproduction are sensitive life history stages that
 could be detrimentally affected for immigrants in non-native habitats. We
 propose that ‘immigrant reproductive dysfunction’ is a hitherto overlooked
 aspect of reproductive isolation caused by natural selection on
 immigrants. This idea is supported by results from experiments on an
 externally fertilizing fish (sand goby, Pomatoschistus minutus). Growth
 and condition of adults were not affected by non-native salinity whereas
 males spawning as immigrants had lower sperm motility and hatching success
 than residents. We interpret these results as evidence for local
 adaptation or acclimation of sperm, and possibly also components of
 paternal care. The resulting loss in fitness, which we call ‘immigrant
 reproductive dysfunction’, has the potential to reduce gene flow between
 populations with locally adapted reproduction, and it may play a role in
 species distributions and speciation.
description: Svensson-IRD-growthTreatment effects on growth rate and weight. Species: sand goby Pomatoschistus minutus. Three localities were used: Bökevik, a bay near Sven Lovén Centre for Marine Infrastructure, Kristineberg (Skagerrak, 58°14'55"N 11°26'51"E, salinity 16-35 PSU), Sandviken, a bay near the town of Västervik (Baltic Sea proper, 57°44'15"N 16°42'29"E, salinity 6-7.5 PSU) and the bays Svartvik and Byviken near the town of Härnösand (Gulf of Bothnia, 62°33'08"N 17°52'00"E and 62°35'22"N 17°54'38"E, salinity 3-5.5 PSU). File: Svensson-IRD-growth. Population: Harnosand (Härnösand), Vastervik (Västervik) and Kristineberg. Treatment: Resident 6 PSU for Harnosand and Vastervik, 32 PSU for Kristineberg, immigrant 32 PSU for Harnosand and Vastervik, 6 PSU for Kristineberg. Sex: Male or female. Length March: total length in mm in March 2012. Length Length May: total length in mm in May 2012. Weight May: Total body weight (g) in may.Svensson-IRD-reproductionTreatment effect on reproductive success. Species: sand goby Pomatoschistus minutus. Three localities were used: Bökevik, a bay near Sven Lovén Centre for Marine Infrastructure, Kristineberg (Skagerrak, 58°14'55"N 11°26'51"E, salinity 16-35 PSU), Sandviken, a bay near the town of Västervik (Baltic Sea proper, 57°44'15"N 16°42'29"E, salinity 6-7.5 PSU) and the bays Svartvik and Byviken near the town of Härnösand (Gulf of Bothnia, 62°33'08"N 17°52'00"E and 62°35'22"N 17°54'38"E, salinity 3-5.5 PSU). File: Svensson-IRD-reproduction. ID: The authors’ identification code for the replicate. Female treatment: Resident 6 PSU for Harnosand and Vastervik, 32 PSU for Kristineberg, immigrant 32 PSU for Harnosand and Vastervik, 6 PSU for Kristineberg. Male treatment: Resident 6 PSU for Harnosand and Vastervik, 32 PSU for Kristineberg, immigrant 32 PSU for Harnosand and Vastervik, 6 PSU for Kristineberg. Male population: Harnosand (Härnösand), Vastervik (Västervik) and Kristineberg. Female population: Harnosand (Härnösand), Vastervik (Västervik) and Kristineberg. Vastervik and Harnosand pooled. Female population not pooled: Harnosand (Härnösand), Vastervik (Västervik) and Kristineberg. Vastervik and Harnosand not pooled. Male in treatment: Weeks or months. The males had been in treatment at two different lengths. Spawned egg area cm2: The area (cm2) of the original egg clutch. Final egg area cm2: The area (cm2) of the final egg clutch. Days to clutch loss: The number of days until the clutch was lost (if lost).Svensson-IRD-spermTreatment effect on sperm motility. Species: sand goby Pomatoschistus minutus. Two localities were used: Bökevik, a bay near Sven Lovén Centre for Marine Infrastructure, Kristineberg (Skagerrak, 58°14'55"N 11°26'51"E, salinity 16-35 PSU) and the bays Svartvik and Byviken near the town of Härnösand (Gulf of Bothnia, 62°33'08"N 17°52'00"E and 62°35'22"N 17°54'38"E, salinity 3-5.5 PSU). File: Svensson-IRD-sperm. Male origin: Harnosand (Härnösand) and Kristineberg. ID: The authors’ identification number of the males. Sperm motility 31 PSU NaCl: Proportion of motile sperm in 31 PSU NaCl (square-root arcsine transformed). Sperm motility 6 PSU NaCl: Proportion of motile sperm in 6 PSU NaCl (square-root arcsine transformed).