Jorge Assis

Universidade do Algarve | UALG · Centro de Ciências do Mar (CCMAR)

Past climate-driven range shifts shaped intraspecific diversities of species world-wide. Earlier studies, focused on glacial refugia, might have overlooked genetic erosion at lower latitudes associated with warmer periods. For marine species able to colonize deeper waters, depth shifts might be important for local persistence, preventing some latit...

Intra-specific genetic variability is critical for species adaptation and evolution and yet it is generally overlooked in projections of the biological consequences of climate change. We ask whether ongoing climate changes can cause the loss of important gene pools from North Atlantic relict kelp forests that persisted over glacial-interglacial cyc...

Motivation The availability of user-friendly, high-resolution global environmental datasets is crucial for bioclimatic modelling. For terrestrial environments, WorldClim has served this purpose since 2005, but equivalent marine data only became available in 2012, with pioneer initiatives like Bio-ORACLE providing data layers for several ecological...

Aquaculture has become the primary supplier of fish for human consumption, with production increasing every year since 1990 (FAO, 2020). At the same time, up to 89% of the world’s capture fisheries are fully exploited, overexploited, or collapsed. While some fisheries may have increased yields due to climate change in the short term, global fisheri...

Climate change is producing shifts in the distribution and abundance of marine species. Such is the case of kelp forests, important marine ecosystem-structuring species whose distributional range limits have been shifting worldwide. Synthesizing long-term time series of kelp forest observations is therefore vital for understanding the drivers shapi...

Connectivity plays a key role in the effectiveness of MPA networks ensuring metapopulation resilience through gene flow and recruitment effect. Yet, despite its recognized importance for proper MPA network functioning, connectivity is not often assessed and is very seldomly used in marine spatial planning. Here, we combined biophysical models with...

We review the current knowledge of the biodiversity of the ocean as well as the levels of decline and threat for species and habitats. The lack of understanding of the distribution of life in the ocean is identified as a significant barrier to restoring its biodiversity and health. We explore why the science of taxonomy has failed to deliver knowle...

Aim Over the past 50 years, anthropogenic activities have led to the disappearance of approximately one‐third of the world's mangrove forests and their associated ecosystem services. The synergetic combined effect of projected climate change is likely to further impact mangroves in the years to come, whether by range expansions associated with warm...

Ocean warming is one of the most important factors in shaping the spatial distribution and genetic biodiversity of marine organisms worldwide. The northwest Pacific has been broadly illustrated as an essential seaweed diversity hotspot. However, few studies have yet investigated in this region on whether and how past and ongoing climate warming imp...

Marine connectivity studies are essential to provide a framework for analyzing long-term source sink dynamics, as well as determining how species dispersal affects population genetic diversity and structure on large and regional scales. Here we present the first large-scale genetic population and connectivity study of the widespread seagrass specie...

The magnitude and distribution of net primary production (NPP) in the coastal ocean remains poorly constrained, particularly for shallow marine vegetation. Here, using a compilation of in situ annual NPP measurements across >400 sites in 72 geographic ecoregions, we provide global predictions of the productivity of seaweed habitats, which form the...

Population connectivity influences the distribution of genetic diversity and divergence along a species range, as the likelihood of extinction or differentiation increases in isolated populations. However, there is still poor understanding of the processes mediating inter-population dispersal in marine species that are sessile and lack planktonic l...

Aim Macroalgal habitats are believed to be the most extensive and productive of all coastal vegetated ecosystems. In stark contrast to the growing attention on their contribution to carbon export and sequestration, understanding of their global extent and production is limited and these have remained poorly assessed for decades. Here we report a fi...

Aim: Drivers of extant population genetic structure include past climate-driven range shifts and vicariant events, as well as gene flow mediated by dispersal and habitat continuity. Their integration as alternative or complementary drivers is often missing or incomplete, potentially overlooking relevant processes and time scales. Here we ask whethe...

Accelerating warming and associated loss of sea ice are expected to promote the expansion of coastal marine forests (macrophytes) along the massive Arctic coastlines. Yet, this region has received much less attention compared to other global oceans. The available future projections of Arctic macrophytes are still limited to few species and regions,...

Phenotypic plasticity and local adaptation can adjust individual responses to environmental changes across species’ ranges. Studies addressing the implications of such traits have been underrepresented in the marine environment. Sargassum cymosum represents an ideal model to test phenotypic plasticity, as populations along the southwestern Atlantic...

Aim Marine forests of brown macroalgae create essential habitats for coastal species and support invaluable ecological services. Here, we provide the first global analysis of species richness and endemicity of both the kelp and fucoid biomes. Location Global. Time period Contemporary. Major taxa studied Marine forests of brown macroalgae, fo...

Drastic losses of kelp forest habitat have already occurred in the southern part of the OSPAR area with significant declines at several locations elsewhere. Considering the sensitivity of this complex and highly productive habitat to cumulative effects of multiple pressures, and the increasing threat posed by climate change, the nominated kelp fore...

Sargassum thunbergii is a brown macroalga endemic to the northwest Pacific. It plays important ecological roles in the structure and maintenance of coastal marine ecosystems. The bioactive compounds extracted from S. thunbergii have been extensively documented for potential use in anti-obesity, anti-inflammatory activity, anti-tumor, anti-oxidant a...

Marine Protected Areas (MPAs) must function as networks with sufficient stepping-stone continuity between suitable habitats to ensure the conservation of naturally connected regional pools of biodiversity in the long-term. For most marine biodiversity, population connectivity is mediated by passively dispersed planktonic stages with contrasting dis...

Glaciation‐induced environmental changes during the last glacial maximum (LGM) have strongly influenced species’ distributions and genetic diversity patterns in the northern high latitudes. However, these effects have seldom been assessed on sessile species in the Northwest Pacific. Herein, we chose the brown alga Sargassum thunbergii to test this...

Aim: With climate change challenging marine biodiversity and resource management, it is crucial to anticipate future latitudinal and depth shifts under contrasting global change scenarios to support policy-relevant biodiversity impact assessments [e.g., Intergovernmental Panel on Climate Change (IPCC)]. We aim to demonstrate the ben- efits of compl...

Seagrasses play a vital role in structuring coastal marine ecosystems, but their distributional range and genetic diversity have declined rapidly over the past decades. In order to improve conservation of seagrass species, it is important to predict how climate change may impact their ranges. Such predictions are typically made with correlative spe...

Kelps are canopy-forming brown seaweed sustaining critical ecosystem services in coastal habitats, including shelter and nursery grounds, and providing food resources to a myriad of associated species. This study modeled the fundamental niche of Laminaria abyssalis along the Brazilian continental margin, an endemic species of the South Atlantic, to...

Seagrasses play a vital role in structuring coastal marine ecosystems, but their distributional range and genetic diversity have declined rapidly over the past decades. In order to improve conservation of seagrass species, it is important to predict how climate change may impact their ranges. Such predictions are typically made with correlative spe...

Natural hybridization can play a significant role in evolutionary processes and influence the adaptive diversification and speci-ation of brown seaweeds. However, this phenomenon is as yet unknown in Saccharina kelps. Saccharina angustata and two varieties of Saccharina japonica (S. japonica var. japonica and S. japonica var. diabolica) partly over...

The need for international cooperation in marine resource management and conservation has been reflected in the increasing number of agreements aiming for effective and well-connected networks of Marine Protected Areas (MPAs). However, the extent to which individual MPAs are connected remains mostly unknown. Here, we use a biophysical model tuned w...

Climate driven range shifts are driving the redistribution of marine species and threatening the functioning and stability of marine ecosystems. For species that are the structural basis of marine ecosystems, such effects can be magnified into drastic loss of ecosystem functioning and resilience. Rhodoliths are unattached calcareous red algae that...

In recent decades, the ocean is becoming less oxygenated due to the combined effect of global warming and the spread of coastal eutrophication, with extensive consequences to marine ecosystems. Past mass extinctions were at least in part due to anoxic conditions in the oceans. Thus, we should be concerned about ongoing and projected declining avail...

The coastal zone, where most of the Brazilian population lives, plays a central role for discussing vulnerability and adaptation strategies to climate change. Besides saltmarshes, mangroves and coral reefs, this region also presents seagrass beds, macroalgae and rhodolith beds, forming underwater forests, which are key habitats for services such as...

The Arctic climate is changing rapidly. The warming and resultant longer open water periods suggest a potential for expansion of marine vegetation along the vast Arctic coastline. We compiled and reviewed the scattered time series on Arctic marine vegetation and explored trends for macroalgae and eelgrass (Zostera marina). We identified a total of...

Knowledge on genetic structure is key to understand species connectivity patterns and to define the spatiotemporal scales over which conservation management plans should be designed and implemented. The distribution of genetic diversity (within and amongst populations) greatly influences species ability to cope and adapt to environmental changes, u...

Contents Dataset S1. Records of occurrence used to model the ecological niche of Paramuricea clavata. Table S1. Environment predictors used in ecological niche modelling. Figure S1. Spatial autocorrelation of environmental predictors within occurrence records. Figure S2. Spatial distribution of the records of occurrence used to model the ecological...

The High Level Panel for Sustainable Ocean Economy (https://oceanpanel.org/) has commissioned a series of “Blue Papers” to explore pressing challenges at the nexus of the ocean and the economy. This paper is part of a series of 16 papers to be published between November 2019 and October 2020. It addresses how multiple human impacts will impact bi...

Species distribution records are a prerequisite to follow climate-induced range shifts across space and time. However, synthesizing information from various sources such as peer-reviewed literature, herbaria, digital repositories and citizen science initiatives is not only costly and time consuming, but also challenging, as data may contain themati...

Marine climate change mitigation initiatives have recently attracted a great deal of interest in the role of natural carbon sinks, particularly on coastal systems. Brown seaweeds of the genus Sargassum are the largest canopy-forming algae in tropical and subtropical environments, with a wide global distribution on rocky reefs and as floating stands...

Marine landings in Portugal have decreased at a higher rate than fishing effort in the last 20 years. Identifying the variables driving the quantity and composition of landings is pivotal to understand the dynamics of the fisheries sector, which entails complex social and environmental aspects. In this study, we investigate the main drivers of mari...

The ‘Abundant-Centre Hypothesis’ is a well-established but controversial hypothesis stating that the abundance of a species is highest at the centre of its range and decreases towards the edges, where conditions are unfavourable. As genetic diversity depends on population size, edge populations are expected to show lower intra-population genetic di...

Marine bioinvasions are increasing worldwide by a number of factors related to the anthroposphere, such as higher ship traffic, climate change and biotic communities' alterations. Generating information about species with high invasive potential is necessary to inform management decisions aiming to prevent their arrival and spread. Grateloupia turu...

In his News In Depth story “Mystery oil spill threatens marine sanctuary in Brazil” (8 November 2019, p. 672), H. Escobar highlights important ecosystems that have been affected by the spill. However, he did not mention the Brazilian rhodolith beds—the most extensive, abundant, and diverse biogenic carbonate habitats in the South Atlantic. The oil...

Genetic structure in biogeographical transition zones can be shaped by several factors including limited dispersal across barriers, admixture following secondary contact, differential selection, and mating incompatibility. A striking example is found in Northwest France and Northwest Spain, where the estuarine seaweed Fucus ceranoides L. exhibits s...

Environmental conditions shape the occurrence and abundance of habitat-building organisms at global scales. Rhodolith beds structure important hard substrate habitats for a large number of marine benthic organisms. These organisms can benefit local biodiversity levels, but also compete with rhodoliths for essential resources. Therefore, understandi...

R pipelines design to extract daily temperature data, and determine marine heat waves (as defined by Hobday et al., 2016; Progress in Oceanography, Volume 141)

Background: In the ocean, the variability of environmental conditions found along depth gradients exposes populations to contrasting levels of perturbation, which can be reflected in the overall patterns of species genetic diversity. At shallow sites, resource availability may structure large, persistent and well-connected populations with higher...

Please follow the URL for more information: https://github.com/jorgeassis/Contour

Despite the relatively high number of spearfishing practitioners in Portugal, scientific information on spearfishing is limited. A web‐based survey was conducted to obtain socio‐economic information on Portuguese spearfishers, identify the most common fishing habitats, target species, fishing effort, and evaluate their perceptions towards managemen...

Aim: Drivers of intraspecific biodiversity include past climate‐driven range shifts and contemporary ecological conditions mediating connectivity, but these are rarely integrated in a common comprehensive approach. This is particularly relevant for marine organisms, as ocean currents strongly influence population isolation or con- nectivity, keepin...

Climate-driven range-shifts have shaped extant patterns of diversity, including intra-specific population genetic structure. Studies of ancient marine distributions, inferred using phylogeographic and modeling approaches, have focused strongly on marine forests of brown macroalgae (kelps and fucoids), which occur on temperate rocky reefs and suppor...

Long-distance dispersal is one of the main drivers structuring the distribution of marine biodiversity. This study reports the first occurrence of Macrocystis pyrifera and Durvillaea antarctica rafts on the southwestern warm temperate coast of the Atlantic Ocean. Our results indicate that an extreme meteo-oceanographic event, characterized by a nor...

Large-scale research endeavors can be hindered by logistical constraints limiting the amount of available data. For example, global ecological questions require a global dataset, and traditional sampling protocols are often too inefficient for a small research team to collect an adequate amount of data. Citizen science offers an alternative by crow...

Glacial vicariance is regarded as one of the most prevalent drivers of phylogeographic structure and speciation among high-latitude organisms, but direct links between ice advances and range fragmentation have been more difficult to establish in marine than in terrestrial systems. Here we investigate the evolution of largely disjunct (and potential...

Oceanographic features shape the distributional and genetic patterns of marine species by interrupting or promoting connections among populations. Although general patterns commonly arise, distributional ranges and genetic structure are species-specific and do not always comply with the expected trends. By applying a multimarker genetic approach co...