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Author |
John C. Wingfield, J. Patrick Kelley, Fréderic Angelier, Olivier Chastel, Fumin Lei, Sharon E. Lynn, Brooks Miner, Jason E. Davis, Dongming Li, Gang Wang |
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Title |
Organism–environment interactions in a changing world: a mechanistic approach |
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Journal |
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Year |
2011 |
Publication |
Journal of Ornithology |
Abbreviated Journal |
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Volume |
152 |
Issue |
1 |
Pages |
279-288 |
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Abstract  |
Understanding the interactions of an organism and its environment is essential for us to integrate ultimate and proximate causation on a global scale. Organism–environment interaction includes all organisms including animals, plants, and non-eukaryotes, etc. because all of them are responsive to environmental change including those that are human-induced. A mechanistic approach is important for us to understand why some organisms can cope with change and others cannot. Here, we present three examples of environments (“the three poles”) that are changing rapidly and how avian species typical of these ecosystems are responding. These examples include apparently adaptive responses to change in climate (i.e. the predictable environment) in one species in which a lengthened breeding season now allows multiple breeding attempts. Why other species are unable to respond in a similar way remains unclear. A second example describes how changing weather (i.e. the unpredictable) may have disastrous results for breeding success in a species adapted to an extreme cold environment. Implications for climate change in which weather extremes will become more common again suggest a mechanistic approach will be important to understand how organisms may respond. The third example outlines a scenario in which multiple human-induced rapid changes (a combination of predictable and unpredictable such as development, habitat change, introduction of invasive species and climate change) may influence indigenous species in different ways. Organism–environment interaction is a fundamental concept that may unify ultimate and proximate causation and point the way for future investigations striving to understand coping mechanisms in a world where both predictable and unpredictable components of the environment are changing. |
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109 |
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2193-7206 |
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yes |
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Serial |
8221 |
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Author |
Guillaume Schwob, Léa Cabrol, Thomas Saucède, Karin Gérard, Elie Poulin, Julieta Orlando |
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Title |
Unveiling the co-phylogeny signal between plunderfish Harpagifer spp. and their gut microbiomes across the Southern Ocean |
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Journal |
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Year |
2023 |
Publication |
Biorxiv |
Abbreviated Journal |
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Issue |
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Abstract |
Understanding the factors that sculpt fish gut microbiome is challenging, especially in natural populations characterized by high environmental and host genomic complexity. Yet, closely related hosts are valuable models for deciphering the contribution of host evolutionary history to microbiome assembly, through the underscoring of phylosymbiosis and co-phylogeny patterns. Here, we hypothesized that the recent allopatric speciation of Harpagifer across the Southern Ocean (1.2–0.8 Myr) will promote the detection of robust phylogenetic congruence between the host and its microbiome. We characterized the gut mucosa microbiome of 77 individuals from four field-collected species of the plunderfish Harpagifer (Teleostei, Notothenioidei), distributed across three biogeographic regions of the Southern Ocean. We found that seawater physicochemical properties, host phylogeny and geography collectively explained 35% of the variation in bacterial community composition in Harpagifer gut mucosa. The core microbiome of Harpagifer spp. gut mucosa was characterized by a low diversity, mostly driven by selective processes, and dominated by a single Aliivibrio taxon detected in more than 80% of the individuals. Almost half of the core microbiome taxa, including Aliivibrio, harbored co-phylogeny signal at microdiversity resolution with Harpagifer phylogeny. This suggests an intimate symbiotic relationship and a shared evolutionary history with Harpagifer. The robust phylosymbiosis signal emphasizes the relevance of the Harpagifer model to understanding the contribution of fish evolutionary history to the gut microbiome assembly. We propose that the recent allopatric speciation of Harpagifer across the Southern Ocean may have generated the diversification of Aliivibrio into patterns recapitulating the host phylogeny. Importance Although challenging to detect in wild populations, phylogenetic congruence between marine fish and its microbiome is critical, as it allows highlighting potential intimate associations between the hosts and ecologically relevant microbial symbionts.Through a natural system consisting of closely related fish species of the Southern Ocean, our study provides foundational information about the contribution of host evolutionary trajectory on gut microbiome assembly, that represents an important yet underappreciated driver of the global marine fish holobiont. Notably, we unveiled striking evidence of co-diversification between Harpagifer and its microbiome, demonstrating both phylosymbiosis of gut bacterial communities, and co-phylogeny of specific bacterial symbionts, in patterns that mirror the host diversification. Considering the increasing threats that fish species are facing in the Southern Ocean, understanding how the host evolutionary history could drive its microbial symbiont diversification represents a major challenge to better predict the consequences of environmental disturbances on microbiome and host fitness. |
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1044 |
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yes |
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Call Number |
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Serial |
8685 |
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Author |
Karine Delord, Cédric Cotté, Pascal Terray, Charles-André Bost, Henri Weimerskirch, Christophe Barbraud |
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Title |
Factors affecting adult body condition in the endangered northern rockhopper penguin |
Type |
Journal |
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Year |
2021 |
Publication |
Marine Biology |
Abbreviated Journal |
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Volume |
168 |
Issue |
3 |
Pages |
27 |
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Keywords |
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Abstract |
Understanding the factors that drive the dynamics of populations of long‐lived species presents a unique challenge for conservation management. Here, we investigated long-term change in the body condition of adult northern rockhopper penguins Eudyptes moseleyi at Amsterdam Island, southern Indian Ocean, which hosts 5–10% of the global population of this endangered species. Analysis of a long‐term dataset (1994–2016), concurrent to the population's rapid decline, revealed no trend in adult northern rockhopper penguin body condition over time at the stages considered in this study, i.e. breeding and moulting. However, body condition varied between years and sexes and part of this variation was explained by environmental factors. Males were on average in better condition than females whatever the stage and individuals on average were in better condition during the moulting compared to the breeding period. The environmental conditions [sea surface temperature anomaly (SSTa), Subtropical Indian Ocean Dipole (SIOD) and Southern Annular Mode (SAM)] appeared to impact non-linearly the body condition. Overall, females were in better condition for negative values of SAM, SIOD and SSTa. The body condition of males exhibited similar but less complex and more significant patterns, with decreasing body condition for increasing SAM, SIOD and SSTa. The absence of long-term trends in male and female body condition suggests that the very low reproductive output and declining population since 1997 is probably not the result of environmental conditions during pre-breeding and pre-moult and necessitates further research into possible drivers during the breeding season. |
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109,394 |
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Bachelor's thesis |
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ISSN |
1432-1793 |
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yes |
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Call Number |
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Serial |
7792 |
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Author |
Lynner Colton, Long Maureen D, |
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Title |
Sub-slab anisotropy beneath the Sumatra and circum-Pacific subduction zones from source-side shear wave splitting observations
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Type |
Journal Article |
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Year |
2014 |
Publication |
Geochemistry, Geophysics, Geosystems |
Abbreviated Journal |
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Volume |
15 |
Issue |
6 |
Pages |
2262-2281 |
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Keywords |
source-side splitting, sub-slab anisotropy, shear wave splitting, 7240 Subduction zones, 7208 Mantle, |
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Abstract |
Understanding the dynamics of subduction is critical to our overall understanding of plate tectonics and the solid Earth system. Observations of seismic anisotropy can yield constraints on deformation patterns in the mantle surrounding subducting slabs, providing a tool for studying subduction dynamics. While many observations of seismic anisotropy have been made in subduction systems, our understanding of the mantle beneath subducting slabs remains tenuous due to the difficulty of constraining anisotropy in the sub-slab region. Recently, the source-side shear wave splitting technique has been refined and applied to several subduction systems worldwide, making accurate and direct measurements of sub-slab anisotropy feasible and offering unprecedented spatial and depth coverage in the sub-slab mantle. Here we present source-side shear wave splitting measurements for the Central America, Alaska-Aleutians, Sumatra, Ryukyu, and Izu-Bonin-Japan-Kurile subduction systems. We find that measured fast splitting directions in these regions generally fall into two broad categories, aligning either with the strike of the trench or with the motion of the subducting slab relative to the overriding plate. Trench parallel fast splitting directions dominate beneath the Izu-Bonin, Japan, and southern Kurile slabs and part of the Sumatra system, while fast directions that parallel the motion of the downgoing plate dominate in the Ryukyu, Central America, northern Kurile, western Sumatra, and Alaska-Aleutian regions. We find that plate motion parallel fast splitting directions in the sub-slab mantle are more common than previously thought. We observe a correlation between fast direction and age of the subducting lithosphere; older lithosphere (>95 Ma) is associated with trench parallel splitting while younger lithosphere (<95 Ma) is associated with plate motion parallel fast splitting directions. Finally, we observe source-side splitting for deep earthquakes (transition zone depths) beneath Japan and Sumatra, suggesting the presence of anisotropy at midmantle depths beneath these regions.
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Programme |
133 |
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ISSN |
1525-2027 |
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yes |
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Serial |
5036 |
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Author |
Rochelle Constantine, Debbie Steel, Judy Allen, Megan Anderson, Olive Andrews, C. Scott Baker, Peta Beeman, Daniel Burns, Jean-Benoît Charrassin, Simon Childerhouse, Michael Double, Paul Ensor, Trish Franklin, Wally Franklin, Nick Gales, Claire Garrigue, Nadine Gibbs, Peter Harrison, Nan Hauser, Amanda Hutsel, Curt Jenner, Micheline-Nicole Jenner, Greg Kaufman, Anne Macie, David Mattila, Carlos Olavarría, Adrian Oosterman, David Paton, Michael Poole, Jooke Robbins, Natalie Schmitt, Peter Stevick, Alden Tagarino, Kirsten Thompson, Juney Ward |
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Title |
Remote Antarctic feeding ground important for east Australian humpback whales |
Type |
Journal |
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Year |
2014 |
Publication |
Marine Biology |
Abbreviated Journal |
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Volume |
161 |
Issue |
5 |
Pages |
1087-1093 |
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Keywords |
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Abstract |
Understanding the dynamics of population recovery is particularly complex when an organism has multiple, remote breeding and feeding grounds separated by one of the longest known migration routes. This study reports on the most comprehensive assessment of humpback whale (Megaptera novaeangliae) movements between remote Antarctic waters south of New Zealand and east Australia (EA), and the migratory corridors and breeding grounds of Australia and Oceania. A total of 112 individual whales were identified; 57 from microsatellites and 61 by fluke with 23 % (n = 26) matched to sites outside Antarctica. Despite large datasets from other southern regions being included in the comparison, the whales were predominantly linked to EA (n = 24). Only two matches to the Oceania catalogues directly north was surprising; therefore the primary feeding grounds of these endangered whales still remain unknown. The confirmation of the Balleny Islands as an important feeding ground for EA whales could provide an insight into reasons behind the rapid recovery of this population. Determining the feeding grounds of Oceania’s whales may explain whether prey energetics or migration length are limiting factors to their recovery and will allow an understanding of future ecosystem changes in these whales. |
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1014 |
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1432-1793 |
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yes |
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Serial |
8160 |
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Author |
Yves Le Bras, Joffrey Jouma’a, Baptiste Picard, Christophe Guinet |
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Title |
How Elephant Seals (Mirounga leonina) Adjust Their Fine Scale Horizontal Movement and Diving Behaviour in Relation to Prey Encounter Rate |
Type |
Journal |
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Year |
2016 |
Publication |
Plos one |
Abbreviated Journal |
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Volume |
11 |
Issue |
12 |
Pages |
e0167226 |
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Keywords |
Foraging Predation Acceleration Animal behavior Predator-prey dynamics Seals Swimming Water columns |
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Abstract |
Understanding the diving behaviour of diving predators in relation to concomitant prey distribution could have major practical applications in conservation biology by allowing the assessment of how changes in fine scale prey distribution impact foraging efficiency and ultimately population dynamics. The southern elephant seal (Mirounga leonina, hereafter SES), the largest phocid, is a major predator of the southern ocean feeding on myctophids and cephalopods. Because of its large size it can carry bio-loggers with minimal disturbance. Moreover, it has great diving abilities and a wide foraging habitat. Thus, the SES is a well suited model species to study predator diving behaviour and the distribution of ecologically important prey species in the Southern Ocean. In this study, we examined how SESs adjust their diving behaviour and horizontal movements in response to fine scale prey encounter densities using high resolution accelerometers, magnetometers, pressure sensors and GPS loggers. When high prey encounter rates were encountered, animals responded by (1) diving and returning to the surface with steeper angles, reducing the duration of transit dive phases (thus improving dive efficiency), and (2) exhibiting more horizontally and vertically sinuous bottom phases. In these cases, the distance travelled horizontally at the surface was reduced. This behaviour is likely to counteract horizontal displacement from water currents, as they try to remain within favourable prey patches. The prey encounter rate at the bottom of dives decreased with increasing diving depth, suggesting a combined effect of decreased accessibility and prey density with increasing depth. Prey encounter rate also decreased when the bottom phases of dives were spread across larger vertical extents of the water column. This result suggests that the vertical aggregation of prey can regulate prey density, and as a consequence impact the foraging success of SESs. To our knowledge, this is one of only a handful of studies showing how the vertical distributions and structure of prey fields influence the prey encounter rates of a diving predator. |
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Programme |
109 |
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ISSN |
1932-6203 |
ISBN |
1932-6203 |
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yes |
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Serial |
6607 |
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Author |
Christophe Sauser, Karine Delord, Christophe Barbraud |
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Title |
Demographic sensitivity to environmental forcings: a multi-trait, multi-colony approach |
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Journal |
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Year |
2021 |
Publication |
Oikos |
Abbreviated Journal |
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Volume |
130 |
Issue |
6 |
Pages |
943-957 |
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Keywords |
Antarctic bottom–up capture–mark–recapture demography elasticity matrix population model multi-colony perturbation analysis sea ice seabirds top–down |
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Abstract |
Understanding the demographic responses of wild animal populations to different factors is fundamental to make reliable prediction of population dynamics. Both bottom–up processes and top–down regulation operate in terrestrial and marine ecosystems, but their relative contribution remains insufficiently known. In addition, direct weather effects on demographic rates have been overlooked in marine ecosystems and inferences on the demographic effects of environmental drivers were overwhelmingly made from single study sites. Here, we evaluate the relative effects of bottom–up, top–down and weather processes on four vital rates and on population growth rates of a long-lived seabird, the snow petrel Pagodroma nivea, within three different breeding colonies. We used multistate capture–recapture modelling and perturbation analyses from a matrix population model based on a 36-year-long (1981–2017) individual monitoring dataset to quantify the different drivers (predation, climatic and weather covariates) of probabilities of survival, breeding, hatching and fledging according to colony, sex and breeding status of individuals. Results show that bottom–up forces and local weather affected breeding parameters, and that survival was driven by top–down regulation pressure and bottom–up processes. Breeding parameters differed between colonies and survival was sex-specific. Sensitivity analysis revealed that population regulation was mainly driven by bottom–up processes and that top–down processes played a minor role. However, there were major differences between colonies about the importance of how local weather processes affected population growth rate. Our study brings new insights into the drivers of demographic processes in a marine meso-predator, and how these drivers vary according to colonies and individual characteristics. We emphasize the importance of considering multiple study sites to make robust inferences on the effects of environmental drivers on wildlife demography. More generally, robust conclusions about the importance of environmental drivers on demography rely on considering multiple causal effects at multiple sites, while accounting for individual characteristics. |
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109 |
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ISSN |
1600-0706 |
ISBN |
1600-0706 |
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yes |
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Call Number |
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Serial |
8039 |
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Julie M. Jones, Sarah T. Gille, Hugues Goosse, Nerilie J. Abram, Pablo O. Canziani, Dan J. Charman, Kyle R. Clem, Xavier Crosta, Casimir de Lavergne, Ian Eisenman, Matthew H. England, Ryan L. Fogt, Leela M. Frankcombe, Gareth J. Marshall, Valérie Masson-Delmotte, Adele K. Morrison, Anaïs J. Orsi, Marilyn N. Raphael, James A. Renwick, David P. Schneider, Graham R. Simpkins, Eric J. Steig, Barbara Stenni, Didier Swingedouw, Tessa R. Vance |
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Title |
Assessing recent trends in high-latitude Southern Hemisphere surface climate |
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Journal |
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Year |
2016 |
Publication |
Nature Climate Change |
Abbreviated Journal |
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Volume |
6 |
Issue |
10 |
Pages |
917-926 |
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Keywords |
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Abstract |
Understanding the causes of recent climatic trends and variability in the high-latitude Southern Hemisphere is hampered by a short instrumental record. Here, we analyse recent atmosphere, surface ocean and sea-ice observations in this region and assess their trends in the context of palaeoclimate records and climate model simulations. Over the 36-year satellite era, significant linear trends in annual mean sea-ice extent, surface temperature and sea-level pressure are superimposed on large interannual to decadal variability. Most observed trends, however, are not unusual when compared with Antarctic palaeoclimate records of the past two centuries. With the exception of the positive trend in the Southern Annular Mode, climate model simulations that include anthropogenic forcing are not compatible with the observed trends. This suggests that natural variability overwhelms the forced response in the observations, but the models may not fully represent this natural variability or may overestimate the magnitude of the forced response. |
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Programme |
1154 |
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1758-6798 |
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1758-6798 |
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yes |
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6737 |
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Author |
D’Amico S., Collins, T., Marx J.C. & Feller G. |
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Title |
Activity-stability relationships in extremophilic enzymes. |
Type |
Conference - International - Poster |
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Year |
2004 |
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Abstract |
Understanding Protein Stability, Stockholm, Suède |
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193 |
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yes |
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Call Number |
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Serial |
3915 |
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Author |
Alessio Gusmeroli, Erin Pettit, Catherine Ritz, Joseph Kennedy, Maurine Montagnat, Eric
Lefebvre, Gael Durand, Sepp Kipfstuhl, and Simon Sheldon. |
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Title |
The relationship between climate and ice rheology at Dome C, East Antarctica: a comparison of fabric determined by borehole sonic logging and thin sections. |
Type |
Conference - International - Communication |
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Year |
2011 |
Publication |
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Volume |
Vol. 13, EGU2011-2341, 2011 |
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Abstract |
Understanding past climate changes as recorded in annual layers within ice sheets is a societal and scientific priority. Oxygen isotopes from several deep ice-cores in Greenland and Antarctica have revealed oscillations with a 100 kyr periodicity extending back at least 740 kyr BP. The EPICA Dome C ice core, the longest climate record obtained from ice, records eight glacial-interglacial transitions where abrupt climate transitions typically separate warm periods (interglacial) from cool periods (glacial). These warm and cool periods are referred to as Marine Isotope Stages (MIS).
Many scientists have observed that the physical properties of glacial ice differs from those of interglacial ice. Glacial ice typically has smaller crystals, higher impurity content, and stronger fabric (preferred orientation of crystal c-axes). Because ice deformation is sensitive to the orientation of crystals, ice flow patterns are sensitive to the fabric and, therefore, to this glacial-interglacial dichotomy. Indeed at Dome C an abrupt, unexpected strengthening of the fabric at the depth of 1750 m marks the transition between the warm MIS5 and the cold MIS6. Because there is a positive feedback between fabric development and ice deformation, changes in ice fabric may be therefore used to understand climate transitions.
We present a vertical-profile of compressional (P) wave speeds acquired every 0.1m in the 3.2 km-deep EPICA Dome C borehole. Each measurements samples ice crystals within a volume approximately 3 m long and 2 m wide ice. We relate the P-wave speeds to fabric through the known seismic anisotropy of a single ice-crystals (P-wave speed is 5% faster when propagates along the crystallographic c-axis than the basal plane). We integrate this seismically-derived fabric profile with the more sparse (about 100 m for most of the core) thin-section-derived fabric to present a more complete vertical-profile of fabric. We provide a preliminary comparison of the shifts in fabric which occur at each of the abrupt climate transitions and relate these to other measurements made on the ice core and in the borehole such as dust and oxygen isotopes. |
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