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J P Boon - One of the best experts on this subject based on the ideXlab platform.
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imposex and organotin concentrations in Buccinum Undatum and neptunea antiqua from the north sea relationship to shipping density and hydrographical conditions
Marine Environmental Research, 2003Co-Authors: Cato Ten C Hallerstjabbes, J W M Wegener, Bert Van Hattum, John F Kemp, Embartus Ten Hallers, Tarren Reitsema, J P BoonAbstract:The presence and the development of imposex were investigated in the common whelk (Buccinum Undatum) and the red whelk (Neptunea antiqua) from the open North Sea and the Skagerrak. Imposex development was related to levels of organotins in penisme/topic-snails/">snails and in the fine fractions ( or = 100 gt per day passing within 15 Nautical miles of the sampling station, shipping levels being: high (> 10 ships day(-1)), intermediate (5--10 ships day(-1)), and low (< 5 ships day(-1)). Sampling stations were also classified according to presence or absence of a vertically stratified water column. In the penisme/topic-snails/">snails the body levels of the butyltin metabolites MBT and DBT and the parent phenyltin compound TPT, were higher than those of TBT and PT metabolites. In the sediment, the parent compounds and the mono-substituted metabolites MBT and MPT were present in the highest concentrations. The highest body levels of all organotin compounds and the highest imposex indices for the common whelk were found at those locations in the Southern Bight and the German Bight that had a high shipping density as well as a homogeneously mixed water column during the whole year. At these locations sediment levels of organotins were also higher than at other sites. In contrast, the body levels of organotins were low and imposex was sometimes even completely absent in penisme/topic-snails/">snails from stratified deep-water stations in the Skagerrak, despite a very high shipping density in the entrance area of the Baltic. In sediments from stratified locations with low or intermediate shipping densities, organotin compounds were below or close to their respective limits of detection. These stations were located in areas with a stratified water column during the whole year. The results can be explained by postulating a much higher resistance for dissolved organotins to migrate through a pycnocline. Organotins could only transgress through a pycnocline when adsorbed to settling particles that manage to transgress the boundary between layers. N. antiqua could only be obtained in sufficient numbers from deeper water stations, which almost all had a stratified water column. At stations where both snail species were obtained and imposex was present, the imposex index was higher in the red whelk. Hence N. antiqua seems to be the more sensitive species of the two. In the red whelk, imposex development increased with shipping density too, though in the smaller samples the trend was not significant. Average biota-sediment accumulation factors (BSAFs; normalised for lipid content in penisme/topic-snails/">snails and TOC content in the fraction < 63 microm in sediments) for Buccinum ranged from 0.4 to 1.0 for butyltins and were similar to literature values reported for TBT in other marine species. Higher average BSAF values were found for phenyltins 1.5 (MPT) to 17 (TPT). The high values for TPT match the ranges expected from equilibrium partitioning concepts of persistent hydrophobic compounds. The ratio of live penisme/topic-snails/">snails to the total number of live penisme/topic-snails/">snails plus empty shells ranged between 2.5 and 93%. This parameter might be a useful indicator to compare past and present densities of populations of both species in different areas of the North Sea.
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cytochrome p450 differences in normal and imposex affected female whelk Buccinum Undatum from the open north sea
Marine Environmental Research, 2002Co-Authors: Miguel M Santos, J P Boon, C Ten C Hallerstjabbes, Natividade Vieira, Cinta PorteAbstract:Abstract Normal and imposex-affected female Buccinum Undatum were sampled from the open North Sea at three locations, one with low, and two with high shipping densities. Cytochrome P450 components and P450 aromatase activity were determined in the microsomal fractions isolated from pooled digestive gland/gonads. Cytochrome P450 aromatase activity was significantly higher (P
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levels of polybrominated diphenyl ether pbde flame retardants in animals representing different trophic levels of the north sea food web
Environmental Science & Technology, 2002Co-Authors: J P Boon, Jacob De Boer, Wilma E Lewis, Michael R Tjoenachoy, C R Allchin, Cato Ten C Hallerstjabbes, Bart N ZegersAbstract:The levels of individual PBDE congeners were investigated in the invertebrate species whelk (Buccinum Undatum), seastar (Asterias rubens), and hermit crab (Pagurus bernhardus), the gadoid fish species whiting (Merlangius merlangus) and cod (Gadus morhua), and the marine mammal species harbor seal (Phoca vitulina) and harbor porpoise (Phocoena phocoena). These species are all important representatives of different trophic levels of the North Sea food web. All six major PBDE congeners detected (BDEs 28, 47, 99, 100, 153, and 154) are most prevalent in the commercial Penta-BDE formulation. There is no evidence for the occurrence of the Octa-BDE formulation in the North Sea food web, since its dominant congener, BDE183, was never detected. BDE209, the main congener (>97%) in the Deca-BDE formulation, was detected only in a minority of the samples and always in concentrations around the limit of detection. Since BDE209 is often the major BDE congener in sediments from the area, the main reason for its low conc...
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levels of polybrominated diphenyl ether pbde flame retardants in animals representing different trophic levels of the north sea food web
Environmental Science & Technology, 2002Co-Authors: J P Boon, Jacob De Boer, Wilma E Lewis, Michael R Tjoenachoy, C R Allchin, Cato Ten C Hallerstjabbes, Robin J Law, Bart N ZegersAbstract:The levels of individual PBDE congeners were investigated in the invertebrate species whelk (Buccinum Undatum), seastar (Asterias rubens), and hermit crab (Pagurus bernhardus), the gadoid fish species whiting (Merlangius merlangus) and cod (Gadus morhua), and the marine mammal species harbor seal (Phoca vitulina) and harbor porpoise (Phocoena phocoena). These species are all important representatives of different trophic levels of the North Sea food web. All six major PBDE congeners detected (BDEs 28, 47, 99, 100, 153, and 154) are most prevalent in the commercial Penta-BDE formulation. There is no evidence for the occurrence of the Octa-BDE formulation in the North Sea food web, since its dominant congener, BDE183, was never detected. BDE209, the main congener (> 97%) in the Deca-BDE formulation, was detected only in a minority of the samples and always in concentrations around the limit of detection. Since BDE209 is often the major BDE congener in sediments from the area, the main reason for its low concentrations in biota from the North Sea seems to be a relatively low bioaccumulation potential. This can either be due to a low uptake rate of the very large molecule or a relatively rapid excretion after biotransformation. Since all invertebrates investigated are sentinel species, they are highly representative for the area of capture. The highest lipid-normalized concentrations of PBDEs in the invertebrates occurred near the mouth of the river Tees at the East coast of the UK. The geographical distribution of the PBDEs can be explained by the residual currents in the area. The direction of these currents differs between the summer and the winter season as a result of the presence or absence of vertical summer stratification of the deeper waters north of the Dogger Bank. Summer stratification results in the development of a density-driven bottom water current formed after the onset of vertical stratification of the water column in May leaving the UK coast near Flamborough Head toward the Dogger Bank. In winter, the residual currents run in a more southerly direction and follow the UK coastline. The distribution pattern of the PCBs and p,p'-DDE in the invertebrates was entirely different from that of the PBDEs, which could be expected, since the use of these organochlorines in western Europe peaked in the 1960s and 1970s but has been forbidden more than two decades ago, whereas the production and use of the penta-BDE formulation is of a more recent origin. The higher trophic levels of the North Sea food web were represented by the predatory gadoid fish species whiting and cod and the marine mammal species harbor seal and harbor porpoise. The lipid-normalized levels of the six major PBDE congeners in fish were similar to the levels in the invertebrates, but a biomagnification step in concentrations of generally more than an order of magnitude occurred from gadoid fish to marine mammals. Based on the limited number of samples, no differences could be observed between harbor seal and harbor porpoise. In summary, the results in three species of sentinel invertebrates from a network of stations covering a major part of the North Sea basin showed that the estuary of the river Tees at the UK East coast is a major source for tri- to hexa-PBDEs. Throughout the food-chain, the most marked increase in (lipid-normalized) levels of all six PBDE congeners occurred from predatory (gadoid) fish to marine mammals, agreeing with the transition from gill-breathing to lung-breathing animals. This has serious consequences for the route of elimination of POPs, since their elimination from the blood into the ambient seawater via the gill-membrane is no longer possible.
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imposex in whelks Buccinum Undatum from the open north sea relation to shipping traffic intensities
Marine Pollution Bulletin, 1994Co-Authors: Cato Ten C Hallerstjabbes, John F Kemp, J P BoonAbstract:Abstract Imposex in female whelks ( Buccinum Undatum L.) from the open North Sea is reported for the first time. The frequency of occurrence of a penis homologue and the mean length of this homologue increased with shipping intensity. Twenty years ago whelks from the area did not show signs of imposex.
Cato Ten C Hallerstjabbes - One of the best experts on this subject based on the ideXlab platform.
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imposex and organotin concentrations in Buccinum Undatum and neptunea antiqua from the north sea relationship to shipping density and hydrographical conditions
Marine Environmental Research, 2003Co-Authors: Cato Ten C Hallerstjabbes, J W M Wegener, Bert Van Hattum, John F Kemp, Embartus Ten Hallers, Tarren Reitsema, J P BoonAbstract:The presence and the development of imposex were investigated in the common whelk (Buccinum Undatum) and the red whelk (Neptunea antiqua) from the open North Sea and the Skagerrak. Imposex development was related to levels of organotins in penisme/topic-snails/">snails and in the fine fractions ( or = 100 gt per day passing within 15 Nautical miles of the sampling station, shipping levels being: high (> 10 ships day(-1)), intermediate (5--10 ships day(-1)), and low (< 5 ships day(-1)). Sampling stations were also classified according to presence or absence of a vertically stratified water column. In the penisme/topic-snails/">snails the body levels of the butyltin metabolites MBT and DBT and the parent phenyltin compound TPT, were higher than those of TBT and PT metabolites. In the sediment, the parent compounds and the mono-substituted metabolites MBT and MPT were present in the highest concentrations. The highest body levels of all organotin compounds and the highest imposex indices for the common whelk were found at those locations in the Southern Bight and the German Bight that had a high shipping density as well as a homogeneously mixed water column during the whole year. At these locations sediment levels of organotins were also higher than at other sites. In contrast, the body levels of organotins were low and imposex was sometimes even completely absent in penisme/topic-snails/">snails from stratified deep-water stations in the Skagerrak, despite a very high shipping density in the entrance area of the Baltic. In sediments from stratified locations with low or intermediate shipping densities, organotin compounds were below or close to their respective limits of detection. These stations were located in areas with a stratified water column during the whole year. The results can be explained by postulating a much higher resistance for dissolved organotins to migrate through a pycnocline. Organotins could only transgress through a pycnocline when adsorbed to settling particles that manage to transgress the boundary between layers. N. antiqua could only be obtained in sufficient numbers from deeper water stations, which almost all had a stratified water column. At stations where both snail species were obtained and imposex was present, the imposex index was higher in the red whelk. Hence N. antiqua seems to be the more sensitive species of the two. In the red whelk, imposex development increased with shipping density too, though in the smaller samples the trend was not significant. Average biota-sediment accumulation factors (BSAFs; normalised for lipid content in penisme/topic-snails/">snails and TOC content in the fraction < 63 microm in sediments) for Buccinum ranged from 0.4 to 1.0 for butyltins and were similar to literature values reported for TBT in other marine species. Higher average BSAF values were found for phenyltins 1.5 (MPT) to 17 (TPT). The high values for TPT match the ranges expected from equilibrium partitioning concepts of persistent hydrophobic compounds. The ratio of live penisme/topic-snails/">snails to the total number of live penisme/topic-snails/">snails plus empty shells ranged between 2.5 and 93%. This parameter might be a useful indicator to compare past and present densities of populations of both species in different areas of the North Sea.
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levels of polybrominated diphenyl ether pbde flame retardants in animals representing different trophic levels of the north sea food web
Environmental Science & Technology, 2002Co-Authors: J P Boon, Jacob De Boer, Wilma E Lewis, Michael R Tjoenachoy, C R Allchin, Cato Ten C Hallerstjabbes, Bart N ZegersAbstract:The levels of individual PBDE congeners were investigated in the invertebrate species whelk (Buccinum Undatum), seastar (Asterias rubens), and hermit crab (Pagurus bernhardus), the gadoid fish species whiting (Merlangius merlangus) and cod (Gadus morhua), and the marine mammal species harbor seal (Phoca vitulina) and harbor porpoise (Phocoena phocoena). These species are all important representatives of different trophic levels of the North Sea food web. All six major PBDE congeners detected (BDEs 28, 47, 99, 100, 153, and 154) are most prevalent in the commercial Penta-BDE formulation. There is no evidence for the occurrence of the Octa-BDE formulation in the North Sea food web, since its dominant congener, BDE183, was never detected. BDE209, the main congener (>97%) in the Deca-BDE formulation, was detected only in a minority of the samples and always in concentrations around the limit of detection. Since BDE209 is often the major BDE congener in sediments from the area, the main reason for its low conc...
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levels of polybrominated diphenyl ether pbde flame retardants in animals representing different trophic levels of the north sea food web
Environmental Science & Technology, 2002Co-Authors: J P Boon, Jacob De Boer, Wilma E Lewis, Michael R Tjoenachoy, C R Allchin, Cato Ten C Hallerstjabbes, Robin J Law, Bart N ZegersAbstract:The levels of individual PBDE congeners were investigated in the invertebrate species whelk (Buccinum Undatum), seastar (Asterias rubens), and hermit crab (Pagurus bernhardus), the gadoid fish species whiting (Merlangius merlangus) and cod (Gadus morhua), and the marine mammal species harbor seal (Phoca vitulina) and harbor porpoise (Phocoena phocoena). These species are all important representatives of different trophic levels of the North Sea food web. All six major PBDE congeners detected (BDEs 28, 47, 99, 100, 153, and 154) are most prevalent in the commercial Penta-BDE formulation. There is no evidence for the occurrence of the Octa-BDE formulation in the North Sea food web, since its dominant congener, BDE183, was never detected. BDE209, the main congener (> 97%) in the Deca-BDE formulation, was detected only in a minority of the samples and always in concentrations around the limit of detection. Since BDE209 is often the major BDE congener in sediments from the area, the main reason for its low concentrations in biota from the North Sea seems to be a relatively low bioaccumulation potential. This can either be due to a low uptake rate of the very large molecule or a relatively rapid excretion after biotransformation. Since all invertebrates investigated are sentinel species, they are highly representative for the area of capture. The highest lipid-normalized concentrations of PBDEs in the invertebrates occurred near the mouth of the river Tees at the East coast of the UK. The geographical distribution of the PBDEs can be explained by the residual currents in the area. The direction of these currents differs between the summer and the winter season as a result of the presence or absence of vertical summer stratification of the deeper waters north of the Dogger Bank. Summer stratification results in the development of a density-driven bottom water current formed after the onset of vertical stratification of the water column in May leaving the UK coast near Flamborough Head toward the Dogger Bank. In winter, the residual currents run in a more southerly direction and follow the UK coastline. The distribution pattern of the PCBs and p,p'-DDE in the invertebrates was entirely different from that of the PBDEs, which could be expected, since the use of these organochlorines in western Europe peaked in the 1960s and 1970s but has been forbidden more than two decades ago, whereas the production and use of the penta-BDE formulation is of a more recent origin. The higher trophic levels of the North Sea food web were represented by the predatory gadoid fish species whiting and cod and the marine mammal species harbor seal and harbor porpoise. The lipid-normalized levels of the six major PBDE congeners in fish were similar to the levels in the invertebrates, but a biomagnification step in concentrations of generally more than an order of magnitude occurred from gadoid fish to marine mammals. Based on the limited number of samples, no differences could be observed between harbor seal and harbor porpoise. In summary, the results in three species of sentinel invertebrates from a network of stations covering a major part of the North Sea basin showed that the estuary of the river Tees at the UK East coast is a major source for tri- to hexa-PBDEs. Throughout the food-chain, the most marked increase in (lipid-normalized) levels of all six PBDE congeners occurred from predatory (gadoid) fish to marine mammals, agreeing with the transition from gill-breathing to lung-breathing animals. This has serious consequences for the route of elimination of POPs, since their elimination from the blood into the ambient seawater via the gill-membrane is no longer possible.
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imposex induction in laboratory reared juvenile Buccinum Undatum by tributyltin tbt
Environmental Toxicology and Pharmacology, 2002Co-Authors: B P Mensink, Cato Ten C Hallerstjabbes, Bert Van Hattum, Hans Kralt, Dick A Vethaak, J H Koeman, Jan P BoonAbstract:Here we report a series of experiments on the development and occurrence of imposex in the common whelk, Buccinum Undatum, under the influence of (chronic) exposure to butyltin compounds. The main objective of the experiments was to obtain more information about the effects of organotin compounds in the marine environment, which possibly relate to the reported decline of B. Undatum in Dutch coastal waters. In these studies tributyltin (TBT) dose-dependently induced the development of male sexual organs in juvenile whelks. A TBT concentration >7 ng Sn/l induced imposex in juvenile whelks. Growth in TBT-exposed juvenile whelks was significantly reduced compared to the reference group at a nominal TBT dose ≥ 4 ng Sn/l in one of the exposure studies. After 5 years in the laboratory, egg-laying was only observed in reference aquaria. Thus, TBT might impair whelk reproduction through growth reduction. The results showed a sensitivity towards imposex development in different life-stages. Juveniles were the most sensitive, adolescent females also responded, but adult females did not respond to TBT exposure, although they dose-dependently increased their organotin (OT) body-burden when exposed. Environmental TBT during only the in ovo stage, did not result in an increased masculinisation compared to non-exposed developing whelks. Histological studies showed no sterilisation due to mechanical blockage of the (adult) female genital opening by sperm-duct tissue. Gonadal development in 2-year old juveniles was not observed. This implies that the differentiation of a penis and a vas deferens, which already occurred in the first few months after hatching, was not controlled by gonadal factors. No other sexual characteristics than those already visible with the eye were found. TBT inactivated CYP450 to its inactive form CYP420 in in vitro exposure studies with microsomal fractions of whelks. The studies have shown TBT to disrupt sexual development dose dependently in juvenile common whelks. TBT also dose dependently exerts an effect on enzymatic (CYP450) processes. Although no mechanical sterilisation was observed, reproduction might be impaired through growth reduction.
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imposex in whelks Buccinum Undatum from the open north sea relation to shipping traffic intensities
Marine Pollution Bulletin, 1994Co-Authors: Cato Ten C Hallerstjabbes, John F Kemp, J P BoonAbstract:Abstract Imposex in female whelks ( Buccinum Undatum L.) from the open North Sea is reported for the first time. The frequency of occurrence of a penis homologue and the mean length of this homologue increased with shipping intensity. Twenty years ago whelks from the area did not show signs of imposex.
Thatje S - One of the best experts on this subject based on the ideXlab platform.
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Nurse egg consumption and intracapsular development in the common whelk Buccinum Undatum (Linnaeus 1758)
'Springer Science and Business Media LLC', 2016Co-Authors: Ke Smith, Thatje SAbstract:This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record.Intracapsular development is common in marine gastropods. In many species, embryos develop alongside nurse eggs, which provide nutrition during ontogeny. The common whelk Buccinum Undatum is a commercially important North Atlantic shallow-water gastropod. Development is intracapsular in this species, with individuals hatching as crawling juveniles. While its reproductive cycle has been well documented, further work is necessary to provide a complete description of encapsulated development. Here, using B. Undatum egg masses from the south coast of England intracapsular development at 6 °C is described. Number of eggs, veligers and juveniles per capsule are compared, and nurse egg partitioning, timing of nurse egg consumption and intracapsular size differences through development are discussed. Total development took between 133 and 140 days, over which 7 ontogenetic stages were identified. The number of both eggs and veligers were significantly related to capsule volume, with approximately 1 % of eggs developing per capsule. Each early veliger consumed nurse eggs rapidly over just 3–7 days. Within each capsule, initial development was asynchronous, but it became synchronous during the veliger stage. No evidence for cannibalism was found during development, but large size differences between embryos developing within each capsule were observed, and occasionally ‘empty’ veligers were seen, which had not successfully consumed any nurse eggs. These results indicate a high level of competition for nurse eggs within each capsule during development in the common whelk. The initial differences observed in nurse egg uptake may affect individual predisposition in later life.This work was supported by grants from the Total Foundation (Abyss2100) to ST and the Malacological Society to KS
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Thermal tolerance during early ontogeny in the common whelk Buccinum Undatum (Linnaeus 1785): Bioenergetics, nurse egg partitioning and developmental success
'Elsevier BV', 2016Co-Authors: Ke Smith, Thatje S, Hauton CAbstract:This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Temperature is arguably the primary factor affecting development in ectotherms and, as a result, may be the driving force behind setting species' geographic limits. The shallow-water gastropod Buccinum Undatum is distributed widely throughout the North Atlantic, with an overall annual thermal range of below zero to above 22 °C. In UK waters this species is a winter spawner. Egg masses are laid and develop when sea temperatures are at their coolest (4 to 10 °C) indicating future climate warming may have the potential to cause range shifts in this species. In order to examine the potential impacts of ocean warming, we investigate the effects of temperature on the early ontogeny of B. Undatum across a thermal range of 0 to 22 °C. Each egg mass consists of approximately 100 capsules, in which embryos undergo direct development. Successful development was observed at temperatures ranging from 6 to 18 °C. Rates of development increased with temperature, but the proportion of each egg mass developing successfully decreased at the same time. With increasing temperature, the mean early veliger weight increased, but the number of early veligers developing per capsule decreased, suggesting a negative impact on the number of crawl-away juveniles produced per capsule. Elemental analysis showed both carbon (C) and nitrogen (N) to increase with temperature in early veligers but not in hatching juveniles, indicating greater energy reserves are accumulated during early ontogeny to compensate for the higher energetic demands of development at higher temperature. The developmental plasticity observed in B. Undatum suggests this species to be capable of adapting to temperatures above those it currently experiences in nature. B. Undatum may possess a thermal resilience to ocean warming at its current upper temperature distribution limit. This thermal resilience, however, may come at the cost of a reduced offspring number.Thanks are given to the skipper and crew of RV Callista (University of Southampton) for their help with sample collection. Thanks are also given to Shir Akbari (University of Southampton) for his help with elemental analysis, and to Adam Reed, Alastair Brown, and Andrew Oliphant for help with animal maintenance. This work was supported by grants from the Total Foundation (Abyss2100) to S.T. and the Malacological Society to K.S
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The Secret to Successful Deep-Sea Invasion: Does Low Temperature Hold the Key?
'Public Library of Science (PLoS)', 2016Co-Authors: Ke Smith, Thatje SAbstract:This is the final version of the article. Available from Public Library of Science via the DOI in this record.There is a general consensus that today’s deep-sea biodiversity has largely resulted from recurrent invasions and speciations occurring through homogenous waters during periods of the Phanerozoic eon. Migrations likely continue today, primarily via isothermal water columns, such as those typical of Polar Regions, but the necessary ecological and physiological adaptations behind them are poorly understood. In an evolutionary context, understanding the adaptations, which allow for colonisation to high-pressure environments, may enable us to predict future events. In this investigation, we examine pressure tolerance during development, in the shallow-water neogastropod Buccinum Undatum using thermally acclimated egg masses from temperate and sub-polar regions across the species range. Fossil records indicate neogastropods to have a deep-water origin, suggesting shallow-water species may be likely candidates for re-emergence into the deep sea. Our results show population level differences in physiological thresholds, which indicate low temperature acclimation to increase pressure tolerance. These findings imply this species is capable of deep-sea penetration through isothermal water columns prevailing at high latitudes. This study gives new insight into the fundamentals behind past and future colonisation events. Such knowledge is instrumental to understand better how changes in climate envelopes affect the distribution and radiation of species along latitudinal as well as bathymetric temperature gradients.This work was made possible through a grant (Abyss2100) from the Total Foundation to Sven Thatje and from the Malacological Society of London to Kathryn Smith. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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The subtle intracapsular survival of the fittest: maternal investment, sibling conflict, or environmental effects?
'Wiley', 2016Co-Authors: Ke Smith, Thatje SAbstract:This is the final version of the article. Available from Ecological Society of America via the DOI in this record.Developmental resource partitioning and the consequent offspring size variations are of fundamental importance for marine invertebrates, in both an ecological and evolutionary context. Typically, differences are attributed to maternal investment and the environmental factors determining this; additional variables, such as environmental factors affecting development, are rarely discussed. During intracapsular development, for example, sibling conflict has the potential to affect resource partitioning. Here, we investigate encapsulated development in the marine gastropod Buccinum Undatum. We examine the effects of maternal investment and temperature on intracapsular resource partitioning in this species. Reproductive output was positively influenced by maternal investment, but additionally, temperature and sibling conflict significantly affected offspring size, number, and quality during development. Increased temperature led to reduced offspring number, and a combination of high sibling competition and asynchronous early development resulted in a common occurrence of “empty” embryos, which received no nutrition at all. The proportion of empty embryos increased with both temperature and capsule size. Additionally, a novel example of a risk in sibling conflict was observed; embryos cannibalized by others during early development ingested nurse eggs from inside the consumer, killing it in a “Trojan horse” scenario. Our results highlight the complexity surrounding offspring fitness. Encapsulation should be considered as significant in determining maternal output. Considering predicted increases in ocean temperatures, this may impact offspring quality and consequently species distribution and abundance.Thanks are given to Viviers, UK, and Vör Marine Research Center, Iceland, for their help with adult sample collection. Thanks also go to Adam Reed, Alastair Brown, and Andrew Oliphant for help with animal maintenance, and to Andrew Oliphant for helpful discussions on the topic. This work was supported by grants from the Total Foundation (Abyss2100) to S. Thatje and the Malacological Society to K. Smith. We thank two anonymous reviewers for constructive criticism on the draft manuscript
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The metabolic cost of developing under hydrostatic pressure: experimental evidence supports macroecological pattern
'Inter-Research Science Center', 2015Co-Authors: Ke Smith, Brown A, Thatje SAbstract:This is the final version of the article. Available from Inter Research via the DOI in this record.Hydrostatic pressure is the most constant physical parameter on Earth. It increases linearly with water depth and is stable over evolutionary timescales. Despite this, bathymetric shifts in physiological adaptations that are observed in marine invertebrates (e.g. in metabolic rate and egg size) are currently interpreted to result predominantly from decreases in temperature. However, analyses of invertebrate egg size data presented here indicate an increase in egg volume with depth in the absence of a thermal gradient. This suggests hydrostatic pressure may also be important in determining resource allocation to offspring. To test the hypothesis that an increase in energy expenditure during development occurs with increasing hydrostatic pressure, we examined the effects of sustained exposure to pressure (1, 100, 200 and 300 atm) on development of a shallow-water marine gastropod, Buccinum Undatum. Embryos developed successfully at 1, 100 and 200 atm, but the rate of development slowed with increasing pressure (by 3 d at 100 atm and 6 d at 200 atm). No development was observed at 300 atm. In embryos reared at 200 atm, veliger dry weight and carbon and nitrogen biomass were significantly reduced. These results indicate that high pressure significantly increases the metabolic cost associated with development, demonstrating a negative and ultimately critical effect. We hypothesise that pressure imposes increased metabolic cost on all physiological processes. This offers an additional explanation for physiological adaptations observed with increasing depth, indicating that hydrostatic pressure is an important and previously underestimated factor contributing to metabolic theory for most of our biosphere. Hydrostatic pressure may represent a critical physiological limit for the maximum depth distribution of shallow-water fauna.This work was supported by grants from the Total Foundation (Abyss2100) to S.T., and from the Malacological Society of London to K.E.S. and a NERC PhD studentship awarded to A.B. We thank the anonymous reviewers, R. B. Aronson, A. Oliphant, and L. Toth for commenting on the manuscript
Smith, Kathryn E. - One of the best experts on this subject based on the ideXlab platform.
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The metabolic cost of developing under hydrostatic pressure: experimental evidence supports macroecological pattern
'Inter-Research Science Center', 2015Co-Authors: Smith, Kathryn E., Brown Alastair, Thatje SvenAbstract:Hydrostatic pressure is the most constant physical parameter on Earth. It increases linearly with water depth and is stable over evolutionary timescales. Despite this, bathymetric shifts in physiological adaptations that are observed in marine invertebrates (eg in metabolic rate and egg size) are currently interpreted to result predominantly from decreases in temperature. However, analysis of invertebrate egg size data presented here indicates an increase in egg volume with depth in the absence of a thermal gradient. This suggests hydrostatic pressure may also be important in determining resource allocation to offspring. In order to test the hypothesis that an increase in energy expenditure during development occurs with increasing depth, we examined the effect of sustained exposure to pressure (1, 100, 200 and 300 atm) on development of a shallow-water marine gastropod, Buccinum Undatum. Embryos developed successfully at 1, 100 and 200 atm, but the rate of development slowed with increasing pressure (by 3 days at 100 atm and 6 days at 200 atm). No development was observed at 300 atm. In embryos reared at 200 atm, veliger dry weight and carbon and nitrogen biomass were significantly reduced. These results indicate that high pressure significantly increases the metabolic cost associated with development, demonstrating a negative and ultimately critical effect. We hypothesise that pressure imposes increased metabolic cost on all physiological processes. This offers an additional explanation for physiological adaptations observed with increasing depth, indicating that hydrostatic pressure is an important and previously underestimated factor contributing to metabolic theory for approximately 99% of our biosphere. This may represent a critical physiological bottleneck for the maximum depth distribution of shallow-water fauna
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Physiological thresholds through early ontogeny: the effects of temperature and hydrostatic pressure on the common whelk Buccinum Undatum (Linnaeus 1758)
2013Co-Authors: Smith, Kathryn E.Abstract:The eco-physiological thresholds controlling the distribution of marine invertebrates are of significance in understanding the evolution of marine diversity. This includes the direction of species radiation throughout the oceans. Range expansions occur as a result of evolutionary adaptations, or through environmentally or anthropogenically driven shifts in distribution. The success of such events is centred around a species ability to adapt; in order for a migration to be successful, all life history stages must tolerate the conditions of the new habitat. This thesis examines the thermal and hyperbaric thresholds affecting range extension in the marine environment. It focuses on the larval development of the shallow-water North Atlantic gastropod Buccinum Undatum (Linnaeus 1758). The Buccinidae family consists of a wide range of shallow and deepwater species distributed globally. Improved knowledge on this topic will contribute to our understanding of the adaptations influencing both historical and modern shifts in the distribution of species.The thermal and hyperbaric ranges observed during development indicate B. Undatum to have the capacity to develop at both temperatures and pressures outside its current distribution. Thermal acclimation to low temperature was also found to increase pressure tolerance during development. A shift in number of embryos developing and nurse egg partitioning per embryo indicate a decrease in developmental success at temperatures above those it is naturally exposed to. An increase in energetic expenditure, with both increasing temperature and pressure, relates to a rise in the metabolic cost associated with development under either condition. These results, combined with the known life history of B. Undatum, suggest range expansion into deep water may be a plausible scenario, but tolerance of warmer conditions remains questionable due to the cold-induced spawning observed in this species. The results of this thesis support theories of high-latitude migrations into the deep sea via cold, isothermal waters, and indeed, suggest polar temperatures may promote the rate at which such range expansions occur. Additionally, the observed metabolic cost associated with development suggests hydrostatic pressure may induce bathymetric limits, which explain patterns observed in reproductive trends, eco-physiological adaptations, and faunal distribution in marine invertebrates throughout the oceans
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Thermal tolerance during early ontogeny in the common whelk Buccinum Undatum (Linnaeus 1785); bioenergetics, nurse egg partitioning and developmental success
'Elsevier BV', 2013Co-Authors: Smith, Kathryn E., Thatje Sven, Hauton ChrisAbstract:Temperature is arguably the primary factor affecting development in ectotherms and, as a result, may be the driving force behind setting species’ geographic limits. The shallow-water gastropod Buccinum Undatum is distributed widely throughout the North Atlantic, with an overall annual thermal range of below zero to above 22°C. In UK waters this species is a winter spawner. Egg masses are laid and develop when sea temperatures are at their coolest (4 to 10°C) indicating future climate warming may have the potential to cause range shifts in this species. In order to examine the potential impacts of ocean warming, we investigate the effects of temperature on the early ontogeny of B. Undatum across a thermal range of 0 to 22°C. Each egg mass consists of approximately 100 capsules, in which embryos undergo direct development. Successful development was observed at temperatures ranging from 6 to 18?C. Rates of development increased with temperature, but the proportion of each egg mass developing successfully decreased at the same time. With increasing temperature, the number of early veligers developing per capsule decreased and the mean early veliger weight increased. Elemental analysis showed both carbon (C) and nitrogen (N) to increase with temperature in early veligers but not in hatching juveniles, indicating greater energy reserves are accumulated during early ontogeny to compensate for the higher energetic demands of development at higher temperature. The developmental plasticity observed in B. Undatum suggests this species to be capable of adapting to temperatures above those it currently experiences in nature. Buccinum Undatum may possess a thermal resilience to ocean warming at its current upper temperature distribution limit. This thermal resilience, however, may come at the cost of a reduced offspring number
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Nurse egg consumption and intracapsular development in the common whelk Buccinum Undatum (Linnaeus 1758)
'Springer Science and Business Media LLC', 2013Co-Authors: Smith, Kathryn E., Thatje SvenAbstract:Intracapsular development is common in marine gastropods. In many species embryos develop alongside nurse eggs, which provide nutrition during ontogeny. The Common Whelk Buccinum Undatum is a commercially important North Atlantic shallow-water gastropod, which undergoes this type of development, with individuals hatching as crawling juveniles. While its reproductive cycle has been well documented, past observations on the encapsulated development in this species do not match our observations and nurse egg partitioning within a capsule has not previously been discussed. Here, using laboratory reared B. Undatum egg masses from the south coast of England, intracapsular development at 6°C is described including nurse egg partitioning, timing of nurse egg consumption and intracapsular size differences through development. Number of eggs, veligers and juveniles per capsule were also compared. Development took 133 to 140 days, over which 7 ontogenetic stages were identified. Numbers of both eggs and veligers were significantly related to capsule volume. Initial development was asynchronous within each capsule. In total approximately 1% of eggs developed per capsule. Each embryo consumed nurse eggs rapidly over just 3 to 7 days. No evidence for cannibalism was found during development but large size differences between embryos developing within each capsule were observed, and occasionally ‘empty’ veligers were seen which had not successfully consumed any nurse eggs. These results indicate high competition for nurse eggs within each capsule during development in the common whelk. The initial differences observed in embryo size may affect individual predisposition in later life
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The subtle intracapsular survival of the fittest: maternal investment, sibling conflict or environmental effects?
'Wiley', 2013Co-Authors: Smith, Kathryn E., Thatje SvenAbstract:Developmental resource partitioning and the consequent offspring size variations are of fundamental importance for marine invertebrates, in both ecological and evolutionary context. Typically, differences are attributed to maternal investment and the environmental factors determining this; additional variables, such as environmental factors affecting development, are rarely discussed. During intracapsular development for example, sibling conflict has the potential to affect resource partitioning. Here, we investigate encapsulated development in the marine gastropod Buccinum Undatum. We examine the effects of maternal investment and temperature on resource partitioning in this species. Reproductive output was positively influenced by maternal investment but additionally, temperature and sibling conflict significantly affected offspring size, number and quality during development. Increased temperature led to reduced offspring number, and a combination of high sibling competition and asynchronous early development resulted in a common occurrence of ‘empty’ embryos, which received no nutrition at all. The proportion of ‘empty’ embryos increased with both temperature and capsule size. Additionally, a novel example of a risk in sibling conflict was observed; embryos cannibalised by others during early development ingested nurse eggs from inside the consumer, killing it in a ‘Trojan horse’ scenario. Our results highlight the complexity surrounding offspring fitness. Encapsulation should be considered as significant in determining maternal output. Considering predicted increases in ocean temperatures, this may impact offspring quality and consequently species distribution and abundance
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Nurse egg consumption and intracapsular development in the common whelk Buccinum Undatum (Linnaeus 1758)
'Springer Science and Business Media LLC', 2016Co-Authors: Ke Smith, Thatje SAbstract:This is the author accepted manuscript. The final version is available from Springer Verlag via the DOI in this record.Intracapsular development is common in marine gastropods. In many species, embryos develop alongside nurse eggs, which provide nutrition during ontogeny. The common whelk Buccinum Undatum is a commercially important North Atlantic shallow-water gastropod. Development is intracapsular in this species, with individuals hatching as crawling juveniles. While its reproductive cycle has been well documented, further work is necessary to provide a complete description of encapsulated development. Here, using B. Undatum egg masses from the south coast of England intracapsular development at 6 °C is described. Number of eggs, veligers and juveniles per capsule are compared, and nurse egg partitioning, timing of nurse egg consumption and intracapsular size differences through development are discussed. Total development took between 133 and 140 days, over which 7 ontogenetic stages were identified. The number of both eggs and veligers were significantly related to capsule volume, with approximately 1 % of eggs developing per capsule. Each early veliger consumed nurse eggs rapidly over just 3–7 days. Within each capsule, initial development was asynchronous, but it became synchronous during the veliger stage. No evidence for cannibalism was found during development, but large size differences between embryos developing within each capsule were observed, and occasionally ‘empty’ veligers were seen, which had not successfully consumed any nurse eggs. These results indicate a high level of competition for nurse eggs within each capsule during development in the common whelk. The initial differences observed in nurse egg uptake may affect individual predisposition in later life.This work was supported by grants from the Total Foundation (Abyss2100) to ST and the Malacological Society to KS
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Thermal tolerance during early ontogeny in the common whelk Buccinum Undatum (Linnaeus 1785): Bioenergetics, nurse egg partitioning and developmental success
'Elsevier BV', 2016Co-Authors: Ke Smith, Thatje S, Hauton CAbstract:This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Temperature is arguably the primary factor affecting development in ectotherms and, as a result, may be the driving force behind setting species' geographic limits. The shallow-water gastropod Buccinum Undatum is distributed widely throughout the North Atlantic, with an overall annual thermal range of below zero to above 22 °C. In UK waters this species is a winter spawner. Egg masses are laid and develop when sea temperatures are at their coolest (4 to 10 °C) indicating future climate warming may have the potential to cause range shifts in this species. In order to examine the potential impacts of ocean warming, we investigate the effects of temperature on the early ontogeny of B. Undatum across a thermal range of 0 to 22 °C. Each egg mass consists of approximately 100 capsules, in which embryos undergo direct development. Successful development was observed at temperatures ranging from 6 to 18 °C. Rates of development increased with temperature, but the proportion of each egg mass developing successfully decreased at the same time. With increasing temperature, the mean early veliger weight increased, but the number of early veligers developing per capsule decreased, suggesting a negative impact on the number of crawl-away juveniles produced per capsule. Elemental analysis showed both carbon (C) and nitrogen (N) to increase with temperature in early veligers but not in hatching juveniles, indicating greater energy reserves are accumulated during early ontogeny to compensate for the higher energetic demands of development at higher temperature. The developmental plasticity observed in B. Undatum suggests this species to be capable of adapting to temperatures above those it currently experiences in nature. B. Undatum may possess a thermal resilience to ocean warming at its current upper temperature distribution limit. This thermal resilience, however, may come at the cost of a reduced offspring number.Thanks are given to the skipper and crew of RV Callista (University of Southampton) for their help with sample collection. Thanks are also given to Shir Akbari (University of Southampton) for his help with elemental analysis, and to Adam Reed, Alastair Brown, and Andrew Oliphant for help with animal maintenance. This work was supported by grants from the Total Foundation (Abyss2100) to S.T. and the Malacological Society to K.S
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The Secret to Successful Deep-Sea Invasion: Does Low Temperature Hold the Key?
'Public Library of Science (PLoS)', 2016Co-Authors: Ke Smith, Thatje SAbstract:This is the final version of the article. Available from Public Library of Science via the DOI in this record.There is a general consensus that today’s deep-sea biodiversity has largely resulted from recurrent invasions and speciations occurring through homogenous waters during periods of the Phanerozoic eon. Migrations likely continue today, primarily via isothermal water columns, such as those typical of Polar Regions, but the necessary ecological and physiological adaptations behind them are poorly understood. In an evolutionary context, understanding the adaptations, which allow for colonisation to high-pressure environments, may enable us to predict future events. In this investigation, we examine pressure tolerance during development, in the shallow-water neogastropod Buccinum Undatum using thermally acclimated egg masses from temperate and sub-polar regions across the species range. Fossil records indicate neogastropods to have a deep-water origin, suggesting shallow-water species may be likely candidates for re-emergence into the deep sea. Our results show population level differences in physiological thresholds, which indicate low temperature acclimation to increase pressure tolerance. These findings imply this species is capable of deep-sea penetration through isothermal water columns prevailing at high latitudes. This study gives new insight into the fundamentals behind past and future colonisation events. Such knowledge is instrumental to understand better how changes in climate envelopes affect the distribution and radiation of species along latitudinal as well as bathymetric temperature gradients.This work was made possible through a grant (Abyss2100) from the Total Foundation to Sven Thatje and from the Malacological Society of London to Kathryn Smith. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
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The subtle intracapsular survival of the fittest: maternal investment, sibling conflict, or environmental effects?
'Wiley', 2016Co-Authors: Ke Smith, Thatje SAbstract:This is the final version of the article. Available from Ecological Society of America via the DOI in this record.Developmental resource partitioning and the consequent offspring size variations are of fundamental importance for marine invertebrates, in both an ecological and evolutionary context. Typically, differences are attributed to maternal investment and the environmental factors determining this; additional variables, such as environmental factors affecting development, are rarely discussed. During intracapsular development, for example, sibling conflict has the potential to affect resource partitioning. Here, we investigate encapsulated development in the marine gastropod Buccinum Undatum. We examine the effects of maternal investment and temperature on intracapsular resource partitioning in this species. Reproductive output was positively influenced by maternal investment, but additionally, temperature and sibling conflict significantly affected offspring size, number, and quality during development. Increased temperature led to reduced offspring number, and a combination of high sibling competition and asynchronous early development resulted in a common occurrence of “empty” embryos, which received no nutrition at all. The proportion of empty embryos increased with both temperature and capsule size. Additionally, a novel example of a risk in sibling conflict was observed; embryos cannibalized by others during early development ingested nurse eggs from inside the consumer, killing it in a “Trojan horse” scenario. Our results highlight the complexity surrounding offspring fitness. Encapsulation should be considered as significant in determining maternal output. Considering predicted increases in ocean temperatures, this may impact offspring quality and consequently species distribution and abundance.Thanks are given to Viviers, UK, and Vör Marine Research Center, Iceland, for their help with adult sample collection. Thanks also go to Adam Reed, Alastair Brown, and Andrew Oliphant for help with animal maintenance, and to Andrew Oliphant for helpful discussions on the topic. This work was supported by grants from the Total Foundation (Abyss2100) to S. Thatje and the Malacological Society to K. Smith. We thank two anonymous reviewers for constructive criticism on the draft manuscript
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The metabolic cost of developing under hydrostatic pressure: experimental evidence supports macroecological pattern
'Inter-Research Science Center', 2015Co-Authors: Ke Smith, Brown A, Thatje SAbstract:This is the final version of the article. Available from Inter Research via the DOI in this record.Hydrostatic pressure is the most constant physical parameter on Earth. It increases linearly with water depth and is stable over evolutionary timescales. Despite this, bathymetric shifts in physiological adaptations that are observed in marine invertebrates (e.g. in metabolic rate and egg size) are currently interpreted to result predominantly from decreases in temperature. However, analyses of invertebrate egg size data presented here indicate an increase in egg volume with depth in the absence of a thermal gradient. This suggests hydrostatic pressure may also be important in determining resource allocation to offspring. To test the hypothesis that an increase in energy expenditure during development occurs with increasing hydrostatic pressure, we examined the effects of sustained exposure to pressure (1, 100, 200 and 300 atm) on development of a shallow-water marine gastropod, Buccinum Undatum. Embryos developed successfully at 1, 100 and 200 atm, but the rate of development slowed with increasing pressure (by 3 d at 100 atm and 6 d at 200 atm). No development was observed at 300 atm. In embryos reared at 200 atm, veliger dry weight and carbon and nitrogen biomass were significantly reduced. These results indicate that high pressure significantly increases the metabolic cost associated with development, demonstrating a negative and ultimately critical effect. We hypothesise that pressure imposes increased metabolic cost on all physiological processes. This offers an additional explanation for physiological adaptations observed with increasing depth, indicating that hydrostatic pressure is an important and previously underestimated factor contributing to metabolic theory for most of our biosphere. Hydrostatic pressure may represent a critical physiological limit for the maximum depth distribution of shallow-water fauna.This work was supported by grants from the Total Foundation (Abyss2100) to S.T., and from the Malacological Society of London to K.E.S. and a NERC PhD studentship awarded to A.B. We thank the anonymous reviewers, R. B. Aronson, A. Oliphant, and L. Toth for commenting on the manuscript
