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Invasions of fouling organisms that colonize artificial structures are modifying coastal environments. Our goal was to assess harbor conditions including dissolved copper pollution, position in relation to open coast, temperature, and artificial structure density (substrate for fouling) as determinants of macroinvertebrate recruitment. Settlement panels were deployed over a gradient of human coastal modification (28 sites in California and 2 in southern Australia). Non-indigenous macroinvertebrates dominated panel cover (overall by six-fold compared to indigenous taxa). Marinas and sites of heavy shipping showed high macroinvertebrate diversity, contrasting with open-coast sites of lower human impact [Santa Catalina Island (SCI) and one mainland coastal site] where there was low macroinvertebrate fouling. At two SCI sites with low vessel traffic, invertebrates that were rare on exposed panels were more common in a protected space between plastic strips indicating larvae amount does not completely explain low invertebrate diversity, suggesting a contributing role of predators or larval recruitment pattern. While dissolved copper levels correlated strongly with artificial structure measured at the water surface, the pollution gradient was not supported as a driver of macroinvertebrate diversity in semi-partial analysis. Density of artificial structure was supported as a better predictor of macroinvertebrate diversity, including separately analyzed non-indigenous and indigenous groups, than dissolved copper, distance from open coast or temperature variation in semi-partial correlation analysis. An artificial structure density measure may therefore increase power in predicting abundance of fouling organisms and could be useful in moderating the influence of non-indigenous species. more...

We review software for exploring biological evolution from a fun and educational perspective. Our goal is to provide a background explanation of the methods used, terminology, and user experience, and learning outcomes of desktop and mobile evolutionary simulators. Freeware and commercial programs are detailed, with a discussion of how certain software packages can be used in introducing evolutionary theory. more...

Previous analyses of the mitochondrial gene cytochrome c oxidase subunit 1 (COI) and γ-proteobacterial endosymbiont diversity have suggested that the marine bryozoan Bugula neritina is a complex of three cryptic species, namely Types S, D and N. Types D and N were previously reported to have restricted distributions along California (western USA) and Delaware and Connecticut (eastern USA), respectively, whereas Type S is considered widespread in tropical, subtropical and temperate regions due to anthropogenic transport. Here, Bayesian species delimitation analysis of a data set composed of two mitochondrial (COI and large ribosomal RNA subunit [16S]) and two nuclear genes (dynein light chain roadblock type-2 protein [DYN] and voltage-dependent anion-selective channel protein [VDAC]) demonstrated that Types S, D and N correspond to three biological species. This finding was significantly supported, in spite of the combinations of priors applied for ancestral population size and root age. Furthermore, COI sequences were used to assess the introduction patterns of the cosmopolitan Type S species. Two COI haplotypes of Type S (S1a and S1d) were found occurring at a global scale. Mantel tests showed correlation between these haplotypes and local sea surface temperature tolerance. Accordingly, the distributions of Type S haplotypes may reflect intraspecific temperature tolerance variation, in addition to the role of introduction vectors. Finally, we show that the Type N may also have been introduced widely, as this species was found for the first time in Central California and north-eastern Australia. more...

The bryozoan genus Watersipora includes rapidly invading species that are becoming common globally. We used paired-end Illumina sequencing to identify thousands of potentially amplifiable microsatellite loci, enabling researchers to track patterns of the invasive spread, and to facilitate ecological and evolutionary question setting. We describe variability of nine loci within recently introduced populations of two Watersipora species in California. more...

A non-native bryozoan, Schizoporella errata, forms extensive patches of free-living balls and reef-like structures (bryoliths) on the mudflats in south San Francisco Bay, California. The ball-like bryoliths range from 2 to 20 cm in diameter, and the reef-like structures can be nearly 1 m across. While S. errata is known to form bryoliths in other locations, free-living aggregations like these have not been reported. Colony morphology appears to be a plastic trait as analysis of relation- ships among forms using cytochrome oxidase subunit I (COI) nucleotide sequence data revealed no genetic separation. We recorded >50 species of algae and invertebrates living on and in the bryoliths and determined the invasion status for 34 of the 50 species. Of the 34, 25 (74%) were non-natives and included fouling species that require hard substrate. The bryoliths may thus facilitate colonization by invaders on the mudflats and serve as stepping stones between the limited hard substrate habitats in the Bay. more...

The brine shrimp Artemia franciscana was used as a model zooplankter to explore the range and accuracy of quantitative PCR (QPCR) in detecting a target species in plankton community DNA. Specific primers were designed in the 18S ribosomal RNA and mitochondrial cytochrome c oxidase subunit I genes and analyzed by TaqMan and SYBR Green I reporting systems. Assays were sensitive in detecting A. franciscana nauplii in DNA extractions from bulk plankton: a single nauplius was detected when added to 20 mg wet, packed plankton and distinguished from two added nauplii. Indeed, Artemia DNA diluted to 0.1 picograms per reaction (equivalent to 10−5 nauplii) was detectable. Artemia franciscana was detected without coamplification of other plankton, alleviating concern for errors caused by the presence of similar organisms in the plankton community. A natural plankton DNA sample and purified herring sperm DNA inhibited PCR above 100 ng reaction−1, but these samples could be diluted to eliminate inhibition. Because QPCR could detect 10−5 nauplii, dilution solves inhibition without sacrificing sensitivity. This sensitivity allows for analysis of a mass of plankton made large enough sufficient to include a target organism at low density. The newly hatched nauplius (DNA mass = 6. 1 ng) is a useful internal control in experiments examining plankton samples, providing a means of controlling for variations in DNA extraction and amplification efficiency in surveys for species of interest. more...

This special feature: Genetic Structure and Adaptation in Coastal Ecosystems emphasizes the importance of research focused on population genetic structure and evolutionary change for understanding estuarine and coastal communities. Many studies have examined the effect of environmental gradients on community-level patterns in estuarine habitats; however, relatively little is known about the role of genetically based adaptation (the heritable response to these environmental gradients) in these organisms. This special feature presents 11 studies that use a variety of approaches including ecophysiology, ecological genetics, molecular markers, and patterns of gene expression occurring within these populations. These studies provide examples of the role of genetic diversity and adaptation across a diversity of estuarine and coastal environments, and highlight the temporal and spatial scales at which adaptation impinges upon management. This collection of papers is especially timely, given the increasing importance of understanding and predicting the response to global climate change in order to effectively manage these communities. more...

The oligochaete Limnodrilus hoffmeisteri at Foundry Cove (FC), New York evolved genetic resistance to cadmium (Cd) and lost resistance after contaminated sediments were removed by dredging. Selection (on survival time in dissolved Cd) was used to generate tolerance to evaluate fitness cost, the commonplace expectation for evolutionary reversal. The hypothesis that gene flow from neighboring populations could "swamp" resistance was addressed by 16S rDNA sequences. In disagreement with the cost hypothesis, selected-Cd tolerant worms and controls showed no difference in total fecundity or growth rate in environments. Highly-Cd-tolerant worms of the FC-selected population grew rapidly at different temperatures and showed no growth impairment in the presence of Cd, indicating metabolically efficient resistance. Genetic structure at FC was consistent with invasion of genotypes from an adjacent population in the time since dredging. Applying selection to lines from FC and a reference site, demonstrated a more rapid increase in Cd tolerance in FC-origin lines, indicating standing allelic variation for resistance at FC (despite phenotypic erosion). The selection experiment supports the view that resistance is simply controlled--probably by one allele of large effect. Whether such rapid "readaptation" could occur naturally is an important question for understanding broad effects of pollutants. more...

We report the introduction of the encrusting bryozoan Watersipora subtorquata to Atlantic coasts of Europe. This species is highly invasive, having become common on coastlines throughout cool-temperate areas of the world since the 1980s. Confusion exists over the identity of this and other Watersipora species, which lack characters that are conventionally used in bryozoan systematics. W. subtorquata has not been well distinguished from W. cucullata which, reports dating back to the mid 1800s suggest, is native to the Mediterranean Basin or represents an early shipping introduction. W. cucullata has been placed in synonymy with W. subovoidea, a taxon lacking a holotype. We designate a neotype for W. subovoidea, recognizing its conspecificity with W. cucullata, and demonstrate a simple morphometric means of separating this species from W. subtorquata using zooid feature ratios (operculum area versus total frontal shield). An orange watersiporid population that was first recognized in Guernsey, in the European-Atlantic, in 2007, is shown by morphometric and mitochondrial genetic analysis to match W. subtorquata. It contains the commonest, widely introduced COI haplotype that, along with other evidence, suggests recent transfer via shipping traffic to Europe. A second population (previously referred alternatively to W. aterrima or W. subovoidea) has been reported from Brittany and Bordeaux (Atlantic coastline, France). This population is also aligned with W. subtorquata based on morphometrics and COI haplotype. In contrast to the Guernsey introduction, the earlier French-Atlantic introduction appears related to oyster imports from Japan. more...

This study examines the effectiveness of remediating a well-recognized case of heavy metal pollution at Foundry Cove (FC), Hudson River, New York. This tidal freshwater marsh was polluted with battery-factory wastes (1953-1979) and dredged in 1994-1995. Eight years after remediation, dissolved and particulate metals (Cd, Co, Cu, Pb, Ni, and Ag) were found to be lower than levels in the lower Hudson near New York City. Levels of metals (Co, Ni, Cd) on suspended particles were comparatively high. Concentrations of surface sediment Cd throughout the marsh system remain high, but have decreased both in the dredged and undredged areas: Cd was 2.4-230mg/kg dw of sediment in 2005 vs. 109-1500mg/kg in the same area in 1983. The rate of tidal export of Cd from FC has decreased by >300-fold, suggesting that dredging successfully stemmed a major source of Cd to the Hudson River. more...

Nucleotide variation in cytochrome c oxidase subunit I (COI) was used to examine population structure in three invasive bryozoans: Bugula neritina (Linnaeus, 1758), Watersipora subtorquata (d’Orbigny, 1852), and W. arcuata (Banta, 1969). These species are found on ship hulls and have a short (≤2 days) larval phase. Samples were collected from 1998–2001 at multiple sites in Australia, and in Hong Kong, New Zealand, Hawaii, California, Curacao, and England. B. neritina is known to include three cryptic species, including species Type S (Davidson and Haygood in Biol Bull 196:273–280, 1999) which occurs on the east and west coasts of the USA. One haplotype recorded previously in the USA, S1, was found to be widespread, occurring throughout Australia and in Hong Kong, Curacao, Hawaii, and England. W. subtorquata, a Caribbean–Atlantic species which has invaded southern Australia, New Zealand, and California, had low nucleotide diversity in these areas (π=0.0016±0.0014), consisting of three haplotypes connected by one or two nucleotide mutations. W. arcuata, an Eastern-Pacific native, had comparatively high diversity (π=0.0221±0.0115) in introduced populations from Australia and Hawaii. In each species, identical haplotypes were identified on separate coastlines providing evidence of widespread, rather than genetically independent, introductions. The major contrast in nucleotide diversity suggests that different propagule-source models explain introductions. more...

Tracking biological invasion is an essential part of conservation, and identifying invasive species quickly following an introduction can be imperative. Invasive organisms are often difficult to distinguish visually, which can delay appropriate response measures. We have designed a multiplex-PCR system to effectively distinguish colonies of divergent cytochrome oxidase subunit 1 (COI) sequence clades in the bryozoan genus Watersipora, a genus with invasive species which are aggressive foulers of ship hulls, to understand small-scale invasion patterns and the ecology of lineages of different geographic origins. The identification of previously defined COI lineage groups is conducted using PCR reactions containing five primers. Lineage-specific fragment lengths were produced with 100% reliability, suggesting the assay will offer a rapid and economical means of studying invasion dynamics and the role of adaptation in this rapidly invading species complex. more...

Watersipora is an invasive genus of bryozoans, easily dispersed by fouled vessels. We examined Cytochrome c oxidase subunit I haplotypes from introduced populations on the US Pacific coastline to investigate geographic segregation of species and/or haplotypes. In California, the W. subtorquata group fell into three major sub-groups: W. subtorquata clades A and B and W. “new sp.”. W. subtorquata clades A and B were common in southern California south of Point Conception, a recognized biogeographic boundary, whereas further north, W. subtorquata clade A and W. n. sp. were frequent. The southern California region also had colonies of a morphologically distinct species, W. arcuata, also found in southern Australia and Hawaii; COI variation indicates a common ancestral source(s) in these introductions. The distribution of Watersipora-complex lineages on different coastlines is shown to be temperature correlated. Accordingly, pre-exisitng temperature-based adaptations may play a key role in determining invasion patterns. more...