10.5061/DRYAD.PP6BM
MacLeod, Amy
Technische Universität Braunschweig
Rodríguez, Ariel
Bielefeld University
Vences, Miguel
Technische Universität Braunschweig
Orozco-terWengel, Pablo
Cardiff University
García, Carolina
Charles Darwin Foundation
Trillmich, Fritz
Bielefeld University
Gentile, Gabriele
University of Rome Tor Vergata
Caccone, Adalgisa
Yale University
Quezada, Galo
Galápagos National Park Authority, Central Office, Puerto Ayora, Santa
Cruz Island, Galápagos, Ecuador
Steinfartz, Sebastian
Technische Universität Braunschweig
Data from: Hybridization masks speciation in the evolutionary history of
the Galápagos marine iguana
Dryad
dataset
2015
Conolophus subcristatus
Amblyrhynchus cristatus
Holocene
Conolophus marthae
Conolophus pallidus
2015-05-15T14:09:00Z
2015-05-15T14:09:00Z
en
https://doi.org/10.1098/rspb.2015.0425
19278179 bytes
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CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
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.
Dataset_CComplete mitochondrial control region sequences (1181 bp) in 1493
marine iguanas (Amblyrynchus cristatus) sampled across the Galapagos
archipelago.Datasets_F_G_HData from RAD sequencing for 33 marine iguanas
and 8 outgroups. Described as datasets F, G and H in the manuscript. More
information available in the ReadMe file.Dataset_A_concatenated_alignmentA
concatenated alignment of various squamate sequences for nuclear genes:
RAG1, BDNF, R35 and NKTR.Dataset_D_MicrosatsA dataset of 614 marine iguana
samples, genotyped at 12 microsatellite loci and used in analysis to
determine population structure across the
archipelago.Dataset_E_MicrosatData consisting of 474 marine iguanas
sampled from the island San Cristobal, genotyped at 18 microsatellite
loci. The last 20 samples (highlighted in yellow) are individuals
identified as hybrids of migrants from other
islands.Dataset_MSVar_BottleneckData from marine iguanas sampled on San
Cristobal island, genotyped at 18 microsatellite loci and sorted into two
populations: Loberia and Punta Pitt. All individuals with >6%
missing data and any possible vargrants or migrants from other islands
have been removed.Dataset_B_Mitochondrial5557 bp from seven mitochondrial
genes in a representative selection of the three main haplotype lineages
within Amblyrhynchus, and all species of
Conolophus.Morphometry_AmblyrhynchusMeasurements and scale counts taken
from a microsatellite-genotyped marine iguanas from San Cristóbal to
investigate morphological differences between diverged lineages
Galápagos province
Ecuador