Browsing by Author "Morato, Telmo"
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- Dense cold‐water coral garden of paragorgia johnsoni suggests the importance of the Mid‐atlantic ridge for deep‐sea biodiversityPublication . Morato, Telmo; Dominguez-Carrió, Carlos; Mohn, Christian; Ocaña Vicente, Oscar; Ramos, Manuela; Rodrigues, Luís; Sampaio, Íris; Tarnto, A. G.; Fauconnet, Laurence; Tojeira, Ines; Gonçalves, Emanuel J.; Silva, Marina CarreiroMid-ocean ridges generate a myriad of physical oceanographic processes that favor the supply of food and nutrients to suspension- and filter-feeding organisms, such as cold-water corals and deep-sea sponges. However, the pioneering work conducted along the Mid-Atlantic Ridge failed to report the presence of large and dense living coral reefs, coral gardens, or sponge aggregations. Here, we describe the densest, near-natural, and novel octocoral garden composed of large red and white colonies of Paragorgia johnsoni Gray, 1862 discovered at 545–595 m depth on the slopes of the Mid-Atlantic Ridge, in the Azores region. This newly discovered octocoral garden is a good candidate for protection since it fits many of the FAO criteria that define what constitutes a Vulnerable Marine Ecosystem. The observations described here corroborate the existence of a close relationship between the octocoral structure and the ambient currents on ridge-like topographies, providing new insights into the functioning of mid-ocean ridges' ecosystems. The ubiquitous presence of biogenic and geological topographies associated with mid-ocean ridges, which could act as climate refugia, suggests their global importance for deep-sea biodiversity. A better understanding of the processes involved is, therefore, required. Our observations may inspire future deep-sea research initiatives to narrow existing knowledge gaps of biophysical connections with benthic fauna at small spatial scales along mid-ocean ridges.
- Historical gene flow constraints in a northeastern atlantic fish: Phylogeography of the ballan wrasse labrus bergylta across its distribution rangePublication . Almada, Frederico José Oliveira de; Francisco, Sara Martins; Lima, Cristina Silva; Fitzgerald, Richard; Mirimin, Luca; Villegas-Ríos, David; Saborido-Rey, Fran; Afonso, Pedro; Morato, Telmo; Bexiga, Sérgio; Robalo, Joana IsabelThe distribution and demographic patterns of marine organisms in the north Atlantic were largely shaped by climatic changes during the Pleistocene, when recurrent glacial maxima forced them to move south or to survive in northern peri-glacial refugia. These patterns were also influenced by biological and ecological factors intrinsic to each species, namely their dispersion ability. The ballan wrasse (Labrus bergylta), the largest labrid fish along Europe's continental margins, is a target for fisheries and aquaculture industry. The phylogeographic pattern, population structure, potential glacial refugia and recolonization routes for this species were assessed across its full distribution range, using mitochondrial and nuclear markers. The existence of a marked population structure can reflect both recolonization from three distinct glacial refugia and current and past oceanographic circulation patterns. Although isolated in present times, shared haplotypes between continental and Azores populations and historical exchange of migrants in both directions point to a common origin of L. bergylta. This situation is likely to be maintained and/or accentuated by current circulation patterns in the north Atlantic, and may lead to incipient speciation in the already distinct Azorean population. Future monitoring of this species is crucial to evaluate how this species is coping with current environmental changes.