10.5061/DRYAD.FJ6Q573VF
Warren, Dan
0000-0002-8747-2451
Okinawa Institute of Science and Technology
Eytan, Ron
Texas A&M University
Dornburg, Alex
0000-0003-0863-2283
University of North Carolina at Charlotte
University of North Carolina at Charlotte
Iglesias, Teresa
Okinawa Institute of Science and Technology
Brandley, Matt
Carnegie Museum of Natural History
Wainwright, Peter
University of California, Davis
Warren, Dan L.
0000-0002-8747-2451
Okinawa Institute of Science and Technology
Eytan, Ron I.
0000-0002-4625-4589
Texas A&M University at Galveston
Iglesias, Teresa L.
0000-0002-0237-8539
Okinawa Institute of Science and Technology
Brandley, Matthew C.
Carnegie Museum of Natural History
Wainwright, Peter C.
0000-0003-0498-4759
University of California, Davis
Reevaluating claims of ecological speciation in Halichoeres bivittatus
Dryad
dataset
2021
Halichoeres
Halichoeres bivittatus
Wrasse
DNA
alignment
Biogeography
Phylogeography
ecologicical speciation
Parapatric speciation
cytochrome b (CytB)
2022-07-12T00:00:00Z
2021-12-03T00:00:00Z
en
https://doi.org/10.1002/ece3.7936
130057 bytes
3
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Allopatry has traditionally been viewed as the primary driver of
speciation in marine taxa, but the geography of the marine environment and
the larval dispersal capabilities of many marine organisms render this
view somewhat questionable. In marine fishes, one of the earliest and most
highly cited empirical examples of ecological speciation with gene flow is
the slippery dick wrasse, Halichoeres bivittatus. Evidence for this
cryptic or incipient speciation event was primarily in the form of a deep
divergence in a single mitochondrial locus between the northern and
southern Gulf of Mexico, combined with a finding that these two haplotypes
were associated with different habitat types (“tropical” vs.
“subtropical”) in the Florida Keys and Bermuda, where they overlap. Here
we examine habitat assortment in the Florida Keys using a broader sampling
of populations and habitat types than were available for the original
study. We find no evidence to support the claim that haplotype frequencies
differ between habitat types, and little evidence to support any
differences between populations in the Keys. These results undermine
claims of ecological speciation with gene flow in Halichoeres bivittatus.
Future claims of this type should be supported by multiple lines of
evidence that illuminate potential mechanisms and allow researchers to
rule out alternative explanations for spatial patterns of genetic
differences.
We sampled eight populations in the Florida Keys including four
populations on the edge of the continental shelf (Sombrero Light, 11 Foot
Mound, XMuta, and Tennessee Reef), two populations on patch reefs in the
inshore channel (East Washerwoman and East Turtle Shoal), and two grass
beds located directly offshore in water < 2m in depth (near mile
marker 62 on Long Key and behind Keys Marine Lab (KML) on Vaca Key). For
broader geographic context we also sampled fishes from two sites further
north on the gulf coast of Florida, two sites in the Bahamas, and one site
from Belize. Florida and Bahamas specimens were collected in 2005 and
2006, and Belize specimens were collected in 2006. In addition to
comparing fore reef and inshore patch reef, we included the grass bed
habitat as it experiences even greater seasonal and diurnal fluctuations
in temperature than the inshore patch reef and as such provides an
additional test of the proposed habitat segregation. All animal handling
procedures were approved by the University of California, Davis
Institutional Animal Care and Use Committee. Fish were caught using a
combination of hand nets, barrier nets, and otter trawls. Specimens were
euthanized using MS-222 dissolved in seawater, and samples were taken from
muscle tissue and preserved in 95% ethanol. We extracted DNA using
DNeasy™ (Qiagen) columns and PCR amplified a fragment of the
mitochondrial cytochrome B gene using the L14768 and H15496 primers from
Rocha et al. (2005). PCR products were cleaned using ExoSap-IT (USB
Corp.). Purified templates were dye labeled using BigDye (ABI) and
sequenced on an ABI 3077 automated DNA Sanger sequencer. Sequences were
aligned using ClustalW (Thompson, Gibson, and Higgins 2002). Rocha, Luiz
A., D. Ross Robertson, Joe Roman, and Brian W. Bowen. 2005. “Ecological
Speciation in Tropical Reef Fishes.” Proceedings. Biological Sciences /
The Royal Society 272 (1563): 573–79. Thompson, Julie D., Toby J. Gibson,
and Des G. Higgins. 2002. “Multiple Sequence Alignment Using ClustalW and
ClustalX.” Current Protocols in Bioinformatics / Editoral Board, Andreas
D. Baxevanis ... [et Al.] Chapter 2 (August): Unit 2.3.