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International audience; The decline of shark populations in the world ocean is affecting ecosystem structure and function in an unpredictable way and new ecological information is today needed to better understand the role of sharks in their habitats. In particular, the characterization of foraging patterns is crucial to understand and foresee the evolution of dynamics between sharks and their prey. Many shark species use the mesopelagic area as a major foraging ground but the degree to which different pelagic sharks rely on this habitat remains overlooked. In order to depict the vertical dimension of their trophic ecology, we used mercury stable isotopes in the muscle of three pelagic shark species (the blue shark Prionace glauca, the shortfin mako shark Isurus oxyrinchus and the smooth hammerhead shark Sphyrna zygaena) from the northeastern Pacific region. The Δ199Hg values, ranging from 1.40 to 2.13‰ in sharks, suggested a diet mostly based on mesopelagic prey in oceanic habitats. We additionally used carbon and nitrogen stable isotopes (δ13C, δ15N) alone or in combination with Δ199Hg values, to assess resource partitioning between the three shark species. Adding Δ199Hg resulted in a decrease in trophic overlap estimates compared to those based on δ13C/δ15N alone, demonstrating that multi-isotope modeling is needed for accurate trophic description of the three species. Mainly, it reveals that they forage at different average depths and that resource partitioning is mostly expressed through the vertical dimension within pelagic shark assemblages. Concomitantly, muscle total mercury concentration (THg) differed between species and increased with feeding depth. Overall, this study highlights the key role of the mesopelagic zone for shark species foraging among important depth gradients and reports new ecological information on trophic competition using mercury isotopes. It also suggests that foraging depth may play a pivotal role in the differences between muscle THg from co-occurring high trophic level shark species.

WOS:000616240600001; International audience; Early life stages (ELS) of numerous marine invertebrates mustcope with man-made contaminants, including plastic debris, during their pelagic phase. Among the diversity of plastic particles, nano-sized debris, known as nanoplastics, can induce effects with severe outcomes in ELS of various biological models, including the Pacific oyster Crassostrea gigas. Here, we investigated the effects of a sub-lethal dose (0.1 mu g mL(-1)) of 50 nm polystyrene nanobeads (nano-PS) with amine functions on oyster embryos (24 h exposure) and we assessed consequences on larval and adult performances over two generations of oysters. Only a few effects were observed. Lipid analyses revealed that first-generation (G1) embryos exposed to nano-PS displayed a relative increase in cardiolipin content (+9.7%), suggesting a potential modification of mitochondrial functioning. G1-larvae issued from exposed embryos showed decreases in larval growth (-9%) and lipid storage (-20%). No effect was observed at the G1 adult stage in terms of growth, ecophysiological parameters (clearance and respiration rates, absorption efficiency), or reproductive outputs (gonadic development, gamete quality). Second generation (G2) larvae issued from control G1 displayed a significant growth reduction after G2 embryonic exposure to nano-PS (-24%) compared to control (as observed at the first generation), while no intergenerational effect was detected on G2 larvae issued from G1 exposed embryos. Overall, the present experimental study suggests a low incidence of a short embryonic exposure to nano-PS on oyster phenotypes along the entire life cycle until the next larval generation.

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WOS:000614806200005; Ecological research focuses on the spatio-temporal patterns of ecosystems and communities. The recently proposed framework of Community Trajectory Analysis considers community dynamics as trajectories in a chosen space of community resemblance and utilizes geometrical properties of trajectories to compare and analyse temporal changes. Here, we extend the initial framework, which focused on consecutive trajectory segments, by considering additional metrics with respect to initial or baseline states. Addressing questions about community dynamics and more generally temporal and spatial ecological variability requires synthetic and efficient modes of representation. Hence, we propose a set of innovative maps, charts and trajectory roses to represent trajectory properties and complement the panel of traditional modes of representation used in community ecology. We use four case studies to highlight the complementarity and the ability of the new metrics and innovative figures to illustrate ecological trajectories and to facilitate their interpretation. Finally, we encourage ecologists skilled in multivariate analysis to integrate CTA into their toolbox in order to quantitatively evaluate spatio-temporal changes.

WOS:000614643900001; Dimethylsulfoniopropionate (DMSP) plays many important physiological and ecological roles in macroalgae. The most common method to measure DMSP is by gas chromatography analysis of the dimethylsulfide (DMS) produced after NaOH hydrolysis (pH \textgreater 12). Storage of DMS, however, is not recommended for more than a week. We investigated if acidification can be a suitable method to preserve DMSP in macroalgal samples over three months of storage, compared to widely used protocols such as drying and freezing at -20 degrees C. The DMSP content of green (Ulva sp. and Ulva compressa), red (Chondrus crispus), and brown (Bifurcaria bifurcata) macroalgae were analyzed: 24 h after NaOH addition (control values); and after acidification (0.2 mol center dot L HCl-1) for 24 h of fresh material, followed by NaOH addition for 24 h. These values were compared to measurements after 3-month storage of samples that had been either dried in a heater (60 degrees C for a night, and storage at room temperature), or frozen at -20 degrees C, or kept in 0.2 mol center dot L HCl-1. There was no significant difference between DMSP measurements on freshly collected material and after acidification of the samples, whether 24 h later or after 3 months of storage. This was in contrast to 3-month storage protocols involving overnight drying at 60 degrees C (75-98% DMSP loss), and to a lesser degree freezing at -20 degrees C (37-80% DMSP loss). We thus advise to acidify macroalgal samples for preservation over long periods of time rather than drying or freezing, when assaying DMSP content.

WOS:000569919500022; This study was focused on the phenolic content and associated cosmetic activities of seven brown marine macroalgae:Alaria esculenta,Ascophyllum nodosum,Bifurcaria bifurcata,Fucus serratus,Halidrys siliquosa,Himanthalia elongata, andLaminaria ochroleuca, selected for their abundance in Brittany and their phlorotannin production. Phlorotannins were extracted by maceration followed by a liquid/liquid purification to obtain fractions enriched in phlorotannins. Seasonal and yearly variations in phenolic contents were investigated thanks to the Folin-Ciocalteu assay to find the best harvesting season for each species.H-1 nuclear magnetic resonance (NMR) was used to validate the presence of phenolic compounds and to compare the species in terms of phenolic signals, as they produce different phlorotannin molecules. Activities required for cosmetic applications (i.e., radical scavenging, antioxidant, photoprotective, and anti-aging activities) were assessed by in vitro tests. Fucales, especiallyA. nodosum,F. serratus,H. elongata, andH. siliquosa, showed higher phenolic contents than Laminariales.Temporal variations were apparent for five seaweeds with the highest phenolic content, notably in autumn. The phenolic content was high regardless of the season and antioxidant and photoprotective activities were similar to those of commercial molecules, allowing year-round algal harvesting. The anti-aging activity ofA. nodosumandF. serratusfractions was higher than the active tea flavonol, epigallocatechin gallate. These results are promising for the use of abundant marine macroalgae as a source of natural active ingredients for cosmetic applications.

Previous studies have demonstrated that male European lobsters (Homarus gammarus) use chemical and visual signals as a means of intra-specific communication during agonistic encounters. In this study, we show that they also produce buzzing sounds during these encounters. This result was missed in earlier studies because low frequency buzzing sounds are highly attenuated in tanks, and are thus difficult to detect with hydrophones. To address this issue, we designed a behavioural tank experiment with hydrophones, and accelerometers placed on the lobsters to directly detect their carapace vibrations (i.e. the sources of the buzzing sounds). While we found that both dominant and submissive individuals produced carapace vibrations during every agonistic encounter, very few of the associated buzzing sounds (15 %) were recorded by the hydrophones. This difference is explained by their high attenuations in tanks. We then used the method of algorithmic complexity to analyze the carapace vibration sequences as call-and-response signals between dominant and submissive individuals. Even if some intriguing patterns appeared for closely size-matched pairs (< 5 mm carapace length difference), the results of the analysis did not permit to conclude that the processes underlying these sequences could be differentiated from random ones. Thus, such results prevented any conclusion about acoustic communication at this time. This concurs with both the high attenuation of the buzzing sounds during the experiments and the poor understanding of acoustic perception by lobsters. New approaches that circumvent tank acoustic issues are now required to validate the existence of acoustic communication in lobsters.

WOS:000569774900004; Coastal nursery areas are subjected to a wide range of natural and anthropogenic stressors, including global warming, which indirectly influence trophic food webs. A global rarefaction of n-3 polyunsaturated fatty acids (PUFA) in trophic networks is in progress. The aim of this study was to assess the effect of a reduction in the dietary availability of n-3 PUFA on some molecular and biochemical parameters related to lipid metabolism and oxidative stress response in juvenile European sea bass (Dicentrarchus labrax) raised at two temperatures (15 degrees C and 20 degrees C). Fish were fed for five months with a reference diet (RD; 1.65% n-3 PUFA on a dry matter basis, DM), used as a proxy of trophic networks where n-3 PUFA is plentiful, and a lower n-3 PUFA diet (LD; 0.73% n-3 PUFA DM), designed to mimic a decrease in n-3 PUFA resulting from global changes (the n-3 PUFA levels tested remained above the nutritional minimum required for this species). Results showed that diet did not affect the hepatic expression of some mRNA coding for transcriptional factors involved in regulating the metabolic pathways related to fatty acid bioconversion. Although our molecular analysis was limited to transcript expression, these data suggest the presence of a threshold in the nutritional supply of PUFA above which the activation of these molecular pathways does not occur. However, the expression for most of the transcripts tested was up-regulated at 20 degrees C. Despite the high peroxidation index in fish fed RD, very few modifications of the oxidative stress response were associated with diet. At 20 degrees C, an increase of the enzymatic antioxidant response was observed, but there was no correlation with the peroxidation index or malondialdehyde products.

WOS:000599869000004; Sexual reproduction remains poorly characterized in dinoflagellates. This is especially the case at the molecular level. Here crossing experiments were performed among strains of the toxic dinoflagellate Alexandrium minutum belonging to two genetically divergent groups. Gene expression was compared between sexually compatible and incompatible crosses at the time of gamete fusion and resting cyst (similar to zygote) formation. Not a single transcript was identified as differentially expressed between compatible and incompatible crosses at these two crucial time points of the dinoflagellate life cycle. However, several thousands of transcripts displayed constitutive expression differences between strains. This was especially the case between the strains belonging to the genetically divergent groups. A few hundreds of transcripts were also identified as differentially expressed between strains belonging to opposite mating types. Some of these transcripts displayed homology with the SxtA protein, known to be involved in saxitoxin production in cyanobacteria, as well as with proteins potentially involved in mating in fungi.

WOS:000514604600007; High temperatures disrupt coral-algal symbioses in multiple ways, with negative impacts on the physiology of the coral host, the algal symbiont, and the combined holobiont. Most heat stress studies on hard corals have understandably focused on species trends based on the combined observation of multiple individuals to account for phenotypic plasticity among colonies. As the "average coral" continues to decline while sea temperatures rise, the outlier colonies that exhibit neutral or positive responses to heat stress are coming to represent larger proportions of marginal coral populations. These colonies are those most likely to guide the future trajectory of reef ecosystems, but their dynamics are often obscured by aggregate analyses. To directly measure and analyze intraspecific variation in heat stress responses within a natural coral population, we performed aquarium experiments on sixteen colonies of the structurally important branching coral Montipora digitata from Okinawa Island, Japan. We resolved host and symbiont genotypes, exposed replicate coral fragments to ambient or elevated temperature, and monitored stress-driven differences in host calcification, symbiont photochemistry, and colony mortality. Over the 6-month experiment, six colonies appeared to tolerate stress (exhibiting no major physiological changes), seven were sensitive to stress (exhibiting reduced growth), and three expired. Both host and symbiont genotype contributed to this variation. These results demonstrate the degree to which unique M. digitata holobionts may differentially respond to thermal stress in warming oceans and highlight the important role of intraspecific variation in shaping future reef assemblages.

International audience; Spatial and seasonal dynamics of microbial loop fluxes were investigated in contrasting productivity regimes in the Indian sector of the Southern Ocean. Observations carried out in late summer (February-March 2018; project MOBYDICK) revealed higher microbial biomasses and fluxes in the naturally iron-fertilized surface waters of Kerguelen island in comparison to surrounding off-plateau waters. Differences were most pronounced for bacterial heterotrophic production (2.3-fold), the abundance of heterotrophic nanoflagellates (HNF; 2.7-fold). Independent of site, grazing by HNF was the main loss process of bacterial production (80-100%), while virus-induced mortality was low (\textless 9%). Combining these results with observations from previous investigations during early spring and summer allowed us to describe seasonal patterns in microbial food web fluxes and to compare these to carbon export in the iron-fertilized and high-nutrient, low-chlorophyll (HNLC) Southern Ocean. Our data suggest an overall less efficient microbial food web during spring and summer, when respiration and viral lysis, respectively, represent important loss terms of bacterially-mediated carbon. In late summer, primary production is more efficiently transferred to bacterial biomass and HNF and thus available for higher trophic levels. These results provide a new insight into the seasonal variability and the quantitative importance of microbial food web processes for the fate of primary production in the Southern Ocean.

WOS:000520805600001; Changes in pigment (chlorophyll-a, carotenoids and phycobiliproteins) and mycosporine-like amino acid (MAA) composition were studied in the red edible macroalga Palmaria palmata, harvested between February 2018 and February 2019 at 2 sites from Brittany (France). The results occuring in natural conditions revealed a high seasonal variability that can be related to a combination of environmental parameters, including light, nutrients, temperature, salinity and pH, which may have synergistic or antagonistic effects. A decrease in pigments was observed in summer, matching with the increase in irradiance at the same period. On the contrary, the increase in light from February to May has caused an increase in the total MAA content, confirming the UV-photoprotective role attributed to these compounds. Analysis of the results coupled with the biosynthesis pathway suggests that some MAAs are favoured in the occurrence of high irradiance. In this sense, asterina-330 was synthetized only between March and July and not the rest of the year, supporting its importance in photoprotection. In addition, analysis revealed that nutrient availibility could have a significant influence on MAAs since their synthesis seemed to be limited in summer, despite significant exposure to light. However, this decrease could be due to another potential role of MAAs as a nitrogen source for macroalgae. Thus, the diversity of these compounds and the different synthesis pathways could be explained by different roles including photo-protection and nitrogen source, making MAA multi-purpose protective agents which could play a key role in the adaptation of this species to its changing environment.

Tide prediction machines, prosopography and digital humanities are the three main axes upon which my Master’s degree research project is constructed. This poster explains what these three most important components of my project are and how they link together, with a focus on the digital humanities tools used. I was awarded a travel scholarship to present this poster at the DARIAH Annual Event 2019 in Warsaw on 16 May 2019 as I won DARIAH's Digital Humanities tools and methods blog competition 2019.

MyMaster’s degree research project concerns the history and developmentof analogue tide prediction machines. In this speed lecture presentation I explain how I am using a novel approach to prosopography to study the lives of tide prediction machines. I gave this 5-minute speed lecture atthe International Postgraduate Port and Maritime Studies Network Conference2019 at the University of Dundee on 25April2019. Abstract:Tide Prediction Machines (TPMs) are analogue computers that were used to predict the times of high and low tides worldwide from the end of the 1800s up to the digital age. The first TPM was designed by William Thomson and built in London in 1873. It was developed as a response to increasing pressure from commercial shipping lines towards the middle of the 19th century who wanted a greater number of more accurate tidal predictions more quickly than could be calculated by hand. As well as helping shipping lines and navies to safely navigate the seas and the shores, TPMs became crucial to the building of ports and effective flood defences. Most of the 33 TPMs ever built were constructed in the UK but were then shipped to other countries who wanted to do their own calculations. In this research, prosopography is used to analyse the life cycle of TPMs, from the motivation for producing them to their decommissioning and their status today. Prosopography is a research approach usually used by historians to study the lives of groups of people; only recently has the idea of conducting prosopographical studies of collections of related objects begun to be explored. This is a concept that is developed and utilised in this research. The aim is to find and analyse the common features in the lives of TPMs, which will give an appreciation of their importance, the extent of their use and usefulness, and an impression of the shape of their lives.

International audience; Marine Spatial Planning (MSP) is an integrated and comprehensive approach to ocean governance and is used to establish a rational use of marine space and reconcile conflicting interests of its users. MSP allows both a high level of environmental protection and a wide range of human activities and emphasizes coordinated networks of national, regional and global institutions. This book focuses on the framework of international law behind MSP and especially on the transboundary aspects of MSP. It first sets out a general framework for transboundary MSP and then moves on to compare and assess differences and similarities between different regions. Specific detailed case studies include the EU with the focus on the Baltic Sea and North Sea, the Bay of Bengal and Great Barrier Reef in Australia. The authors examine the national and regional significance of MSP from an integrated and sustainable ocean governance point of view. They also show how transboundary MSP can create opportunities and positive initiatives for cross-border cooperation and contribute to the effective protection of the regional marine environment.

Parallel evolution of similar phenotypes provides strong evidence for the operation of natural selection. Where these phenotypes contribute to reproductive isolation, they further support a role for divergent, habitat-associated selection in speciation. However, the observation of pairs of divergent ecotypes currently occupying contrasting habitats in distinct geographical regions is not sufficient to infer parallel origins. Here we show striking parallel phenotypic divergence between populations of the rocky-shore gastropod, Littorina saxatilis, occupying contrasting habitats exposed to either wave action or crab predation. This divergence is associated with barriers to gene exchange but, nevertheless, genetic variation is more strongly structured by geography than by ecotype. Using approximate Bayesian analysis of sequence data and amplified fragment length polymorphism markers, we show that the ecotypes are likely to have arisen in the face of continuous gene flow and that the demographic separation of ecotypes has occurred in parallel at both regional and local scales. Parameter estimates suggest a long delay between colonization of a locality and ecotype formation, perhaps because the postglacial spread of crab populations was slower than the spread of snails. Adaptive differentiation may not be fully genetically independent despite being demographically parallel. These results provide new insight into a major model of ecologically driven speciation. © 2013 The Authors. Evolution published by Wiley Periodicals, Inc.

Master thesis in Petroleum engineering The transient behavior of the bottomhole pressure during underbalanced drilling operations has been investigated. Focus has been on jointed pipe drilling with gas injection through the drill string. A description is made of a two‐phase drift‐flux model. The model has previously been developed in Matlab and is modeled to simulate the dynamic bottomhole pressure, during transient conditions in underbalanced operations. The original model only recognizes the slug flow regime and its corresponding slip parameters are implemented through the general slip law [29]. Extension has been made to the original model by including a model that distinguishes between bubble flow and slug flow, based on a simplified version of the suggestions made by Caetano [22]. Values for the slip parameters were chosen depending on existing flow pattern. For the transition zone, interpolation technique was used. The velocity profile coefficient for bubble flow was suggested to be 1.0 by Caetano, however, as this made oscillations in the simulation results a value of 1.1 was adapted, as proposed by Lage and Time [34]. Simulation runs of two‐phase flow in a vertical well were performed using the original model, the bubble slip parameters and the flow pattern dependent model. The results of the bubble flow model was compared to the original model, showing that after the unloading sequence, the bottomhole pressure was found to be 18.3 % lower than for the original model. The unloading sequence was also found to last 47 % longer for the bubble flow model. The results gained from the flow pattern dependent model concluded that the slug flow region is the main flow regime during the simulation. However, until break through of gas during the unloading sequence, the bubble flow regime was found to be the primary flow pattern.

Tide prediction machines, prosopography and digital humanities are the three main axes upon which my Master’s degree research project is constructed. This poster explains what these three most important components of my project are and how they link together, with a focus on the digital humanities tools used. I was awarded a travel scholarship to present this poster at the DARIAH Annual Event 2019 in Warsaw on 16 May 2019 as I won DARIAH's Digital Humanities tools and methods blog competition 2019., {"references":["Cartwright, David. Tides. Cambridge: Cambridge University Press, 2000.","K. Verboven, M. Carlier & J. Dumolyn. A short manual to the art of prosopography, in: K. Keats-Rohan (ed.), Prosopography Approaches and Applications. A Handbook. Oxford: Unit for Prosopographical Research (Linacre College), 2007, p. 35-69.","Woodworth, Philip. An inventory of tide prediction machines. Southampton: National Oceanography Centre, 2016."]}

MyMaster’s degree research project concerns the history and developmentof analogue tide prediction machines. In this presentation I explain how the development of tidal theory and in particular the development of tide prediction machines have been shaped by the sea, as well as the novel approach to prosopography I am applying as the methodology and how I'm using digital humanities tools to do so. I gave this 20-minute presentation at the Shaped by the Sea workshop at the University of Manchester on 27June 2019. Abstract:Tide Prediction Machines (TPMs) are analogue computers that were used to predict the times of high and low tides worldwide from the end of the 1800s up to the digital age. The first TPM was designed by William Thomson (later Lord Kelvin) and built in London in 1873. It was developed as a response to increasing pressure from commercial shipping lines towards the middle of the 19th century who wanted a greater number of more accurate tidal predictions more quickly than could be calculated by hand. As well as helping shipping lines and navies to safely navigate the seas and the shores, TPMs became crucial to the building of ports and effective flood defences. Most of the 33 TPMs ever built were constructed in the UK but were then shipped to other countries who wanted to do their own calculations. Oceanographers Joseph Proudman and Arthur Doodson of Liverpool Observatory and Tidal Institute contributed significantly to the development of tidal analysis and to the evolution of TPMs. They and the institution thus gained a worldwide reputation for tidal research and prediction. TPMs were always operated on land, in some cases over 1000 km from the nearest sea or ocean. Prosopography is a research approach usually used by historians to study the lives of groups of people. Given the analogies with human groups, the research hypothesis is that it is possible to apply prosopographic methods to analyse the life cycle of TPMs, from the motivation for producing them to their status after decommissioning and replacement by newer technology. The aim is to find and analyse the common features in the lives of TPMs, which will give an appreciation of their importance, the extent of their use and usefulness, and an impression of the shape of their lives.

My Master’s degree research project concerns the history and development of analogue tide prediction machines. In this speed lecture presentation I explain how I am using a novel approach to prosopography to study the lives of tide prediction machines. I gave this 5-minute speed lecture at the International Postgraduate Port and Maritime Studies Network Conference 2019 at the University of Dundee on 25 April 2019. Abstract: Tide Prediction Machines (TPMs) are analogue computers that were used to predict the times of high and low tides worldwide from the end of the 1800s up to the digital age. The first TPM was designed by William Thomson and built in London in 1873. It was developed as a response to increasing pressure from commercial shipping lines towards the middle of the 19th century who wanted a greater number of more accurate tidal predictions more quickly than could be calculated by hand. As well as helping shipping lines and navies to safely navigate the seas and the shores, TPMs became crucial to the building of ports and effective flood defences. Most of the 33 TPMs ever built were constructed in the UK but were then shipped to other countries who wanted to do their own calculations. In this research, prosopography is used to analyse the life cycle of TPMs, from the motivation for producing them to their decommissioning and their status today. Prosopography is a research approach usually used by historians to study the lives of groups of people; only recently has the idea of conducting prosopographical studies of collections of related objects begun to be explored. This is a concept that is developed and utilised in this research. The aim is to find and analyse the common features in the lives of TPMs, which will give an appreciation of their importance, the extent of their use and usefulness, and an impression of the shape of their lives., {"references":["Cartwright, David. Tides. Cambridge: Cambridge University Press, 2000.","K. Verboven, M. Carlier & J. Dumolyn. A short manual to the art of prosopography, in: K. Keats-Rohan (ed.), Prosopography Approaches and Applications. A Handbook. Oxford: Unit for Prosopographical Research (Linacre College), 2007, p. 35-69.","Woodworth, Philip. An inventory of tide prediction machines. Southampton: National Oceanography Centre, 2016."]}

My Master’s degree research project concerns the history and development of analogue tide prediction machines. In this presentation I explain how the development of tidal theory and in particular the development of tide prediction machines have been shaped by the sea, as well as the novel approach to prosopography I am applying as the methodology and how I'm using digital humanities tools to do so. I gave this 20-minute presentation at the Shaped by the Sea workshop at the University of Manchester on 27 June 2019. Abstract: Tide Prediction Machines (TPMs) are analogue computers that were used to predict the times of high and low tides worldwide from the end of the 1800s up to the digital age. The first TPM was designed by William Thomson (later Lord Kelvin) and built in London in 1873. It was developed as a response to increasing pressure from commercial shipping lines towards the middle of the 19th century who wanted a greater number of more accurate tidal predictions more quickly than could be calculated by hand. As well as helping shipping lines and navies to safely navigate the seas and the shores, TPMs became crucial to the building of ports and effective flood defences. Most of the 33 TPMs ever built were constructed in the UK but were then shipped to other countries who wanted to do their own calculations. Oceanographers Joseph Proudman and Arthur Doodson of Liverpool Observatory and Tidal Institute contributed significantly to the development of tidal analysis and to the evolution of TPMs. They and the institution thus gained a worldwide reputation for tidal research and prediction. TPMs were always operated on land, in some cases over 1000 km from the nearest sea or ocean. Prosopography is a research approach usually used by historians to study the lives of groups of people. Given the analogies with human groups, the research hypothesis is that it is possible to apply prosopographic methods to analyse the life cycle of TPMs, from the motivation for producing them to their status after decommissioning and replacement by newer technology. The aim is to find and analyse the common features in the lives of TPMs, which will give an appreciation of their importance, the extent of their use and usefulness, and an impression of the shape of their lives., {"references":["Cartwright, David. Tides. Cambridge: Cambridge University Press, 2000.","K. Verboven, M. Carlier & J. Dumolyn. A short manual to the art of prosopography, in: K. Keats-Rohan (ed.), Prosopography Approaches and Applications. A Handbook. Oxford: Unit for Prosopographical Research (Linacre College), 2007, p. 35-69.","Woodworth, Philip. An inventory of tide prediction machines. Southampton: National Oceanography Centre, 2016."]}