Phylogeography of Dictyota fasciola and Dictyota mediterranea (Dictyotales, Phaeophyceae): unexpected patterns on the Atlantic-Mediterranean marine transition and taxonomic implications

The Atlantic-Mediterranean marine transition is a fascinating biogeographic region, but still very poorly studied from the point of view of seaweed phylogeography. Dictyota fasciola and D. mediterranea (Dictyotales, Phaeophyceae) are two currently recognized sister species that share a large part of their distribution along the Mediterranean Sea and the Atlantic Ocean, representing a unique study model to understand the diversification processes experienced by macroalgae during and after Messinian at this marine region. In this study, we sampled 102 individuals of D. fasciola and D. mediterranea from 32 localities along their distribution range and sequenced the mitochondrial cox1 and the chloroplast rbcL-rbcS DNA regions for all the samples. Our data do not support the occurrence of two sister species but a morphologically variable and highly genetic diverse species or a complex of species. Most of the observed genetic diversity corresponds to the Mediterranean populations, whereas the Atlantic ones are much more homogeneous. The early-diverged lineages inferred from both mtDNA and cpDNA phylogenetic reconstructions were constituted by samples from the Mediterranean Sea. Together, these results suggest that the Mediterranean Sea acted as a refugium for the D. fasciola-D. mediterranea lineage during the geologic and climatic changes occurred on the region since the Miocene, subsequently dispersing to the Atlantic Ocean

Phylogeography of Dictyota fasciola and Dictyota mediterranea (Dictyotales, Phaeophyceae): unexpected patterns on the Atlantic-Mediterranean marine transition and taxonomic implications

The Atlantic-Mediterranean marine transition is a fascinating biogeographic region, but still very poorly studied from the point of view of seaweed phylogeography. Dictyota fasciola and D. mediterranea (Dictyotales, Phaeophyceae) are two currently recognized sister species that share a large part of their distribution along the Mediterranean Sea and the Atlantic Ocean, representing a unique study model to understand the diversification processes experienced by macroalgae during and after Messinian at this marine region. In this study, we sampled 102 individuals of D. fasciola and D. mediterranea from 32 localities along their distribution range and sequenced the mitochondrial cox1 and the chloroplast rbcL-rbcS DNA regions for all the samples. Our data do not support the occurrence of two sister species but a morphologically variable and highly genetic diverse species or a complex of species. Most of the observed genetic diversity corresponds to the Mediterranean populations, whereas the Atlantic ones are much more homogeneous. The early-diverged lineages inferred from both mtDNA and cpDNA phylogenetic reconstructions were constituted by samples from the Mediterranean Sea. Together, these results suggest that the Mediterranean Sea acted as a refugium for the D. fasciola–D. mediterranea lineage during the geologic and climatic changes occurred on the region since the Miocene, subsequently dispersing to the Atlantic Ocean

The power of gibbon songs : going beyond the research to inform conservation actions

Gibbons (Hylobatidae) are the smallest of the apes, known for their arboreal behavior and stereotyped songs. These species and sex-specific songs are often the subject of detailed studies regarding their evolution, responses to changing environments, involvement in social behavior, and used to design vocalization-based survey techniques to monitor population densities and trends. What is poorly understood is the value and impact of using the science and sound of gibbon vocalization and gibbon stories in education and outreach to complement nongovernmental organizations (NGOs) efforts. We present an example of how Borneo Nature Foundation, a NGOs based in Indonesia, is working to use the recordings of the songs of Bornean white-bearded gibbons (Hylobates albibarbis) to inform conservation actions and education efforts. Gibbons in Indonesia are often poorly known or understood by the public compared to orangutans (Pongo spp). We showcase how a field of study, namely primate acoustics, is an untapped resource to create digital content to engage with local, national and international communities and can be developed into educational tools in the form of storytelling, mobile apps and games, to highlight the plight of these threatened species and how to conserve them

Impacts of fire and prospects for recovery in a tropical peat forest ecosystem

Uncontrolled fires place considerable burdens on forest ecosystems, compromising our ability to meet conservation and restoration goals. A poor understanding of the impacts of fire on ecosystems and their biodiversity exacerbates this challenge, particularly in tropical regions where few studies have applied consistent analytical techniques to examine a broad range of ecological impacts over multiyear time frames. We compiled 16 y of data on ecosystem properties (17 variables) and biodiversity (21 variables) from a tropical peatland in Indonesia to assess fire impacts and infer the potential for recovery. Burned forest experienced altered structural and microclimatic conditions, resulting in a proliferation of nonforest vegetation and erosion of forest ecosystem properties and biodiversity. Compared to unburned forest, habitat structure, tree density, and canopy cover deteriorated by 58 to 98%, while declines in species diversity and abundance were most pronounced for trees, damselflies, and butterflies, particularly for forest specialist species. Tracking ecosystem property and biodiversity datasets over time revealed most to be sensitive to recurrent high-intensity fires within the wider landscape. These megafires immediately compromised water quality and tree reproductive phenology, crashing commercially valuable fish populations within 3 mo and driving a gradual decline in threatened vertebrates over 9 mo. Burned forest remained structurally compromised long after a burn event, but vegetation showed some signs of recovery over a 12-y period. Our findings demonstrate that, if left uncontrolled, fire may be a pervasive threat to the ecological functioning of tropical forests, underscoring the importance of fire prevention and long-term restoration efforts, as exemplified in Indonesia

Ejemplares de Dictyota cyanoloma junto a Dictyota spiralis

Fotografía tomada en Palamós, en enero de 2013 -- 1er premio en el Concurso Fotográfico de SEF (Sociedad Española de Ficología)Dictyota cyanoloma es una alga parda (Phaeophyceae) del Mediterráneo recientemente descrita por Tronholm et al. (2010) cuya distribución actual incluye la Península Ibérica, la región macaronésica, el Adriático y Turquía. Se trata de una especie que vive generalmente en zonas portuarias o en sus alrededores y que según parece se encuentra en expansión. Todo hace pensar que es una especie de reciente introducción en el Mediterráneo. Con el fin de verificar esta hipótesis y conocer el posible origen de la especie, así como su fenología, se está llevando a cabo un proyecto subvencionado por la Fundación Biodiversidad. Por un lado, se estudia la distribución actual de la especie en las costas mediterráneas de la península ibérica. Por otro, se analiza la variabilidad genética de D. cyanoloma y se compara con otras dos especies mediterráneas del género (D. fasciola y D. mediterranea).Peer reviewe

Unexpected diversity patterns in Dictyota Fasciola and Dictyota Mediterranea (Dictyotales, Phaeophyceae)

Trabajo presentado en el XI Congreso de Ficología de Latinoamérica y El Caribe y la IX Reunión Iberoamericana de Ficología, celebrado en Cali (Colombia), del 5 al 10 de noviembre de 2017Dictyota fasciola is a relatively common species of eulittoral pools and the shallow subtidal in the NE Atlantic and the Mediterranean Sea. Dictyota mediterranea is a rarer species, endemic from the coasts of the Mediterranean Sea where it occupies a similar habitat than the preceding species. As occurs in the majority of Dictyota species, these two taxa are notoriously difficult to identify based on morphological, anatomical, or reproductive characters. Indeed, D. mediterranea was reduced to a synonym of D. fasciola by Feldmann (1937) on the basis of similarities in color, width of the axes, and shape of the apices. However, D. mediterranea shows a terete thallus at the base and the apex – but complanate in the middle part – and a multilayered medulla. In contrast, axes of D. fasciola are all complanate, and a multilayered medulla is restricted to the basal parts of the thallus. Previous molecular phylogenetic studies indicated that both species are closely related (Tronholm et al. 2010), but results pointed out clear genetic differentiation among them. In our current project, we aim to examine the evolutionary relationship between these two species from phylogeographic and systematic points of viewFinancial support was provided by Fundación BiodiversidadPeer reviewe

Phenological and molecular studies on the introduced seaweed Dictyota cyanoloma (Dictyotales, Phaeophyceae) along the Mediterranean coast of the Iberian Peninsula

Dictyota cyanoloma, a distinctive brown algal species characterized by a blue-iridescent margin, was recently reported as an introduced species in the Mediterranean Sea (Steen et al., 2016) but little is known about its distribution dynamics, morphological plasticity and genetic structure. In the present integrative study, we evaluate its past and present occurrence along the Mediterranean Iberian coast, assess the species’ phenology in Palamós (Girona, Spain) and analyze the haplotype diversity by sequencing 49 individuals from nine sampling sites for different chloroplast and mitochondrial DNA regions. Although D. cyanoloma currently occurs along the Mediterranean Iberian coast (in 19 of 36 localities sampled between Algeciras and Llançà, mostly in marinas and harbour environments), we were not able to find any herbarium material of this species (at BCN-Phyc and MA) predating the year 1987. In Palamós, D. cyanoloma is present all through the year, with a maximum development in winter and a minimum in summer. Fertile specimens are absent during summer (July and August). Sporophytes are dominant from January to June and dioecious gametophytes were found only in February, March and June. Information about the antheridia, which has never been described before, is provided. Two chloroplast and three mitochondrial haplotypes were observed, indicating that multiple introductions of D. cyanoloma occurred in the study area. Additionally, the genetic structure suggests that spread did not occur through simple advancing wave fronts but by several long-distance dispersal events. Further studies employing microsatellite markers could potentially offer a better resolution to unravel expansion and colonisation dynamics of D. cyanoloma in the Mediterranean Sea.Peer reviewe

Tracing the introduction history of the brown seaweed Dictyota cyanoloma (Phaeophyceae, Dictyotales) in Europe

Dictyota cyanoloma has recently been described from the Mediterranean Sea and Macaronesia but doubt had arisen as to whether this species was truly native in Europe. The species is mainly found on non-natural substrata (harbour walls, marinas, boat hulls, etc.), strongly suggesting that it is an introduction. Molecular sequence information from historical herbarium samples proves the presence of D. cyanoloma in the Adriatic Sea as early as 1935. Since approximately the year 2000, however, the number of records as well as the geographic range of the species has expanded significantly. The presentday distribution of D. cyanoloma occupies most of the Mediterranean Sea, Macaronesia, NW Africa and southern Portugal, but recent records from Galicia and SW England (Falmouth, Cornwall) indicate that the species is rapidly expanding northward. Collections from Australia demonstrated that the species is also present from Perth in Western Australia, over much of the southern Australian coastline up to Minnie Water in New South Wales. Phylogenetic analyses resolve D. cyanoloma in a sister clade to a previously unreported Australian Dictyota species. Analysis of genetic diversity of the mitochondrial markers (nad6-nad11 and atp9-orf11) reveals that even though Australian populations contain a much higher haplotype richness, European populations are also fairly diverse. Furthermore, only two out of 25 haplotypes are shared between both regions. These somewhat counterintuitive results could be indicative of a more complicated introduction history

Tracing the introduction history of the brown seaweed <i>Dictyota cyanoloma</i> (Phaeophyceae, Dictyotales) in Europe

<p><i>Dictyota cyanoloma</i> has recently been described from the Mediterranean Sea and Macaronesia but doubt had arisen as to whether this species was truly native in Europe. The species is mainly found on non-natural substrata (harbour walls, marinas, boat hulls, etc.), strongly suggesting that it is an introduction. Molecular sequence information from historical herbarium samples proves the presence of <i>D. cyanoloma</i> in the Adriatic Sea as early as 1935. Since approximately the year 2000, however, the number of records as well as the geographic range of the species has expanded significantly. The present-day distribution of <i>D. cyanoloma</i> occupies most of the Mediterranean Sea, Macaronesia, NW Africa and southern Portugal, but recent records from Galicia and SW England (Falmouth, Cornwall) indicate that the species is rapidly expanding northward. Collections from Australia demonstrated that the species is also present from Perth in Western Australia, over much of the southern Australian coastline up to Minnie Water in New South Wales. Phylogenetic analyses resolve <i>D. cyanoloma</i> in a sister clade to a previously unreported Australian <i>Dictyota</i> species. Analysis of genetic diversity of the mitochondrial markers (<i>nad</i>6–<i>nad</i>11 and <i>atp</i>9–<i>orf</i>11) reveals that even though Australian populations contain a much higher haplotype richness, European populations are also fairly diverse. Furthermore, only two out of 25 haplotypes are shared between both regions. These somewhat counterintuitive results could be indicative of a more complicated introduction history.</p