Progressive colonization and restricted gene flow shape island-dependent population structure in Galápagos marine iguanas (Amblyrhynchus cristatus)

Steinfartz, Sebastian; Glaberman, Scott; Lanterbecq, Déborah; Russello, Michael A.; Rosa, Sabrina; Hanley, Torrance C.; Márquez, Cruz; Snell, Howard L.; Snell, Heidi M.; Gentile, Gabriele; Dell'Olmo, Giacomo; Powell, Alessandro M.; Caccone, Adalgisa

doi:10.1186/1471-2148-9-297

Cited by 27 publications

(55 citation statements)

References 74 publications

(105 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although only a single species of Amblyrhynchus is recognized, high levels of genetic distinctiveness characterize most of its current island populations [20]. Previous work on a limited number of specimens [20] even indicated the existence of two genetically distinct Amblyrhynchus populations in the northeast (Punta Pitt-PP) and southwest (Lobería-LO; figure 3c) areas of San Cristó bal island, but further information on their distribution and evolutionary history was lacking. San Cristobal is thought to be one of the oldest of the current Galápagos Islands, having emerged between 2.4 and 4.0 Ma [11], and measuring only 550 km 2 in surface area, with 140 km of shoreline.…”

Section: Introductionmentioning

confidence: 99%

“…(ii) Time tree of Galápagos iguanas based on mitochondrial DNA A representative selection of the three main haplotype lineages within Amblyrhynchus [20], including PP and LO, and all species rspb.royalsocietypublishing.org Proc. R. Soc.…”

Section: (B) Molecular Genetic Analysesmentioning

confidence: 99%

“…Amblyrhynchus is a monospecific ancient lineage forming an archipelago-endemic clade with the three species of Galápagos land iguanas (genus Conolophus) [22]. Although only a single species of Amblyrhynchus is recognized, high levels of genetic distinctiveness characterize most of its current island populations [20]. Previous work on a limited number of specimens [20] even indicated the existence of two genetically distinct Amblyrhynchus populations in the northeast (Punta Pitt-PP) and southwest (Lobería-LO; figure 3c) areas of San Cristó bal island, but further information on their distribution and evolutionary history was lacking.…”

Section: Introductionmentioning

confidence: 99%

“…To investigate the contradictory pattern of shallow phylogenetic divergence [21] versus strong genetic population structure [20] in marine iguanas, we first reconstruct a temporal framework for their evolution. We estimate the age of the Conolophus-Amblyrhynchus split from an iguanine time-tree based on protein-coding nuclear genes and multiple temporal calibrations across squamates [23].…”

Section: Introductionmentioning

confidence: 99%

“…Unique among lizards worldwide, they alone have adapted to the marine environment by feeding exclusively on algae in the tidal and subtidal zones, though reproduction is purely terrestrial [18,19]. Being strong swimmers, these large and highly mobile animals have colonized all major and minor islands of the archipelago [20,21]. Amblyrhynchus is a monospecific ancient lineage forming an archipelago-endemic clade with the three species of Galápagos land iguanas (genus Conolophus) [22].…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Hybridization masks speciation in the evolutionary history of the Galápagos marine iguana

et al. 2015

Self Cite

View full text Add to dashboard Cite

The effects of the direct interaction between hybridization and speciation-two major contrasting evolutionary processes-are poorly understood. We present here the evolutionary history of the Galápagos marine iguana (Amblyrhynchus cristatus) and reveal a case of incipient within-island speciation, which is paralleled by between-island hybridization. In-depth genome-wide analyses suggest that Amblyrhynchus diverged from its sister group, the Galápagos land iguanas, around 4.5 million years ago (Ma), but divergence among extant populations is exceedingly young (less than 50 000 years). Despite Amblyrhynchus appearing as a single long-branch species phylogenetically, we find strong population structure between islands, and one case of incipient speciation of sister lineages within the same island-ostensibly initiated by volcanic events. Hybridization between both lineages is exceedingly rare, yet frequent hybridization with migrants from nearby islands is evident. The contemporary snapshot provided by highly variable markers indicates that speciation events may have occurred throughout the evolutionary history of marine iguanas, though these events are not visible in the deeper phylogenetic trees. We hypothesize that the observed interplay of speciation and hybridization might be a mechanism by which local adaptations, generated by incipient speciation, can be absorbed into a common gene pool, thereby enhancing the evolutionary potential of the species as a whole.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: (B) Molecular Genetic Analysesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Hybridization masks speciation in the evolutionary history of the Galápagos marine iguana

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

References

2011

Molecular Ecology

View full text Add to dashboard Cite

Cryptic diversity in Black rats Rattus rattus of the Galápagos Islands, Ecuador

Willows‐Munro

Dowler

Jarcho

et al. 2016

Ecology and Evolution

View full text Add to dashboard Cite

Human activity has facilitated the introduction of a number of alien mammal species to the Galápagos Archipelago. Understanding the phylogeographic history and population genetics of invasive species on the Archipelago is an important step in predicting future spread and designing effective management strategies. In this study, we describe the invasion pathway of Rattus rattus across the Galápagos using microsatellite data, coupled with historical knowledge. Microsatellite genotypes were generated for 581 R. rattus sampled from 15 islands in the archipelago. The genetic data suggest that there are at least three genetic lineages of R. rattus present on the Galápagos Islands. The spatial distributions of these lineages correspond to the main centers of human settlement in the archipelago. There was limited admixture among these three lineages, and these finding coupled with low rates of gene flow among island populations suggests that interisland movement of R. rattus is rare. The low migration among islands recorded for the species will have a positive impact on future eradication efforts.

show abstract

Progressive colonization and restricted gene flow shape island-dependent population structure in Galápagos marine iguanas (Amblyrhynchus cristatus)

Cited by 27 publications

References 74 publications

Hybridization masks speciation in the evolutionary history of the Galápagos marine iguana

Hybridization masks speciation in the evolutionary history of the Galápagos marine iguana

References

Cryptic diversity in Black rats Rattus rattus of the Galápagos Islands, Ecuador

Contact Info

Product

Resources

About