Multi locus analysis of Pristionchus pacificus on La Réunion Island reveals an evolutionary history shaped by multiple introductions, constrained dispersal events and rare out‐crossing

  title={Multi locus analysis of Pristionchus pacificus on La R{\'e}union Island reveals an evolutionary history shaped by multiple introductions, constrained dispersal events and rare out‐crossing},
  author={Katy Morgan and Angela McGaughran and Laure Villate and Matthias Herrmann and Hanh Witte and Gabi Bartelmes and Jacques Rochat and Ralf J. Sommer},
  journal={Molecular Ecology},
Pristionchus pacificus, recently established as a model organism in evolutionary biology, is a cosmopolitan nematode that has a necromenic association with scarab beetles. The diverse array of host beetle species and habitat types occupied by P. pacificus make it a good model for investigating local adaptation to novel environments. Presence of P. pacificus on La Réunion Island, a young volcanic island with a dynamic geological history and a wide variety of ecozones, facilitates such… 
Landscape and oceanic barriers shape dispersal and population structure in the island nematode Pristionchus pacificus
Despite the biological importance and diversity of nematodes, little is known of the factors influencing their dispersal and shaping their evolutionary history. Populations of the cosmopolitan
Two New Species of Pristionchus (Nematoda: Diplogastridae) Support the Biogeographic Importance of Japan for the Evolution of the Genus Pristionchus and the Model System P. pacificus
Two new species of Pristionchus are described, P. maxplancki and P. quartusdecimus, which were isolated from beetles in Japan, supporting the hypothesis that a region including Japan is the origin of diversification of the P. pacificus species complex.
Unraveling the evolutionary history of the nematode Pristionchus pacificus: from lineage diversification to island colonization
This study comprehensively improves previous inferences about the evolutionary history of P. pacificus by employing model-based statistical methods and using a modeling-based approximate Bayesian computation approach to test hypotheses about the order and timing of establishment of the Réunion populations.
Characterization of Genetic Diversity in the Nematode Pristionchus pacificus from Population-Scale Resequencing Data
It is concluded that purifying selection on many mutations with weak effects is a major force shaping genetic diversity in P. pacificus.
The nematode Pristionchus pacificus as a model system for integrative studies in evolutionary biology
Recent attempts to establish the nematode Pristionchus pacificus as a model organism that allows integrative studies of development and evo‐devo, with ecology and population genetics are reviewed.
Molecular evolution and mutation accumulation lines in the nematode Pristionchus pacificus
The combination of mutation rate analysis with intraspecific divergence provides a powerful tool for the reconstruction of the natural history of P. pacificus, and the ecological implication of these findings is discussed.
Environmental Variables Explain Genetic Structure in a Beetle-Associated Nematode
It is shown that significantly more genetic variation in P. pacificus populations is explained by environmental variation than by geographic distances, which supports a strong role for environmental heterogeneity vs. genetic drift in the divergence of populations, which is suggested may be influenced by adaptive forces.
Genomic Profiles of Diversification and Genotype-Phenotype Association in Island Nematode Lineages.
Taking a genome-wide association approach, this work functionally validate a significant genotype-phenotype association for pH tolerance in P. pacificus, which is undergoing heterogeneous genotypic and phenotypic diversification related to both evolutionary and environmental processes.
Two New Pristionchus Species (Nematoda: Diplogastridae) from Taiwan are Part of a Species-cluster Representing the Closest Known Relatives of the Model Organism P. pacificus.
Two new species of Pristionchus are described, P. taiwanensis and P. occultus from Taiwan using morphology, morphometrics, mating experiments and genome- wide sequence analysis, both of which are gonochorists and they are morphologically indistinguishable from P. pacificus.
Variation in rates of spontaneous male production within the nematode species Pristionchus pacificus supports an adaptive role for males and outcrossing
Elevated rates of laboratory male generation appear to occur under environmental conditions which differ from those experienced by populations in nature, which may result in higher outcrossing rates, hence driving increased effective recombination and the creation of potentially adaptive novel allelic combinations.


Haplotype diversity of the nematode Pristionchus pacificus on Réunion in the Indian Ocean suggests multiple independent invasions.
It is described the first account of soil- and beetle-associated nematodes on an island setting by investigating the island of Reunion in the Indian Ocean, establishing Reunion as a case study for nematode island biogeography, in which the analysis of nematODE population genetics and population dynamics can provide insight into evolutionary and ecological processes.
Evolutionary history of Caenorhabditis elegans inferred from microsatellites: evidence for spatial and temporal genetic differentiation and the occurrence of outbreeding.
The previous notion that C. elegans is a colonizer is supported, whereby selfing may permit rapid dispersal within new habitats even in the absence of potential mates, whereas occasional outcrossing may serve to compensate for the disadvantages of inbreeding.
Phenotypic divergence despite high levels of gene flow in Galápagos lava lizards (Microlophus albemarlensis)
It is inferred that gene flow between the habitats on Plaza Sur must be sufficiently high to overcome genetic drift within habitats but that it does not preclude phenotypic differentiation.
Phylogeny of the nematode genus Pristionchus and implications for biodiversity, biogeography and the evolution of hermaphroditism
A robust phylogeny of all 18 available Pristionchus species based on a set of 27 ribosomal protein genes encompassing a total of 10,971 bp indicates that all hermaphroditic species have arisen independently within the genus Pristonchus.
Strong population structure despite evidence of recent migration in a selfing hermaphroditic vertebrate, the mangrove killifish (Kryptolebias marmoratus)
It is indicated that interlocality dispersal and outcross‐mediated genetic recombination play key proximate roles in the local ‘clonal’ dynamics of this species.
The geographic scale of diversification on islands: genetic and morphological divergence at a very small spatial scale in the Mascarene grey white-eye (Aves: Zosterops borbonicus)
A combination of past microallopatry driven by volcanic activity and selection-constrained dispersal along steep ecological gradients is proposed to explain the striking levels of population structure found within the island, although the possibility that genetic differences evolved in situ along the gradient cannot be ruled out at present.
Metabolic rate, genetic and microclimate variation among springtail populations from sub-Antarctic Marion Island
Over the relatively short timescale of Marion Island’s history, the periodic geographic barriers that have driven population differentiation from a molecular perspective may also have resulted in some physiological differentiation of populations.
Contemporary morphological diversification of passerine birds introduced to the Hawaiian archipelago
  • B. Mathys, J. Lockwood
  • Environmental Science, Biology
    Proceedings of the Royal Society B: Biological Sciences
  • 2011
This work examines six passerine bird species that were introduced to the Hawaiian archipelago less than 150 years ago and finds that five of these show morphological divergence among islands from the time since they were established.
Diversity and divergence patterns in regulatory genes suggest differential gene flow in recently derived species of the Hawaiian silversword alliance adaptive radiation (Asteraceae)
The results suggest that adaptively radiating species can exhibit contrasting allele migration rates among loci such that allele movement at specific loci may supersede genetic divergence caused by drift and that lineage divergence during adaptive radiation can be associated with population expansion.