9 research outputs found
Unravelling the macro-evolutionary ecology of fish–jellyfish associations: life in the ‘gingerbread house’
Fish–jellyfish interactions are important factors contributing to fish stock success. Jellyfish can compete with fish for food resources, or feed on fish eggs and larvae, which works to reduce survivorship and recruitment of fish species. However, jellyfish also provide habitat and space for developing larval and juvenile fish which use their hosts as means of protection from predators and feeding opportunities, helping to reduce fish mortality and increase recruitment. Yet, relatively little is known about the evolutionary dynamics and drivers of such associations which would allow for their more effective incorporation into ecosystem models. Here, we found that jellyfish association is a probable adaptive anti-predator strategy for juvenile fish, more likely to evolve in benthic (fish living on the sea floor), benthopelagic (fish living just above the bottom of the seafloor), and reef-associating species than those adapted to other marine habitats. We also found that jellyfish association likely preceded the evolution of a benthic, benthopelagic, and reef-associating lifestyle rather than its evolutionary consequence, as we originally hypothesized. Considering over two-thirds of the associating fish identified here are of economic importance, and the wide-scale occurrence and diversity of species involved, it is clear the formation of fish–jellyfish associations is an important but complex process in relation to the success of fish stocks globally
Protected Areas and Nature Recovery: Achieving the goal to protect 30% of UK land and seas for nature by 2030
This report from the British Ecological Society (published 22 April 2022) examines the Prime Minister’s pledge to protect 30% of UK land and seas by 2030 to support nature recovery
Non-Steroidal Anti-Inflammatory Drugs and Cognitive Function: Are Prostaglandins at the Heart of Cognitive Impairment in Dementia and Delirium ?
Studies of non-steroidal anti-inflammatory drugs (NSAIDs) in rheumatoid arthritis imply that inflammation is important in the development of Alzheimer’s disease (AD). However, these drugs have not alleviated the symptoms of AD in those who have already developed dementia. This suggests that the primary mediator targeted by these drugs, PGE2, is not actively suppressing memory function in AD. Amyloid-β oligomers appear to be important for the mild cognitive changes seen in AD transgenic mice, yet amyloid immunotherapy has also proven unsuccessful in clinical trials. Collectively, these findings indicate that NSAIDs may target a prodromal process in mice that has already passed in those diagnosed with AD, and that synaptic and neuronal loss are key determinants of cognitive dysfunction in AD. While the role of inflammation has not yet become clear, inflammatory processes definitely have a negative impact on cognitive function during episodes of delirium during dementia. Delirium is an acute and profound impairment of cognitive function frequently occurring in aged and demented patients exposed to systemic inflammatory insults, which is now recognised to contribute to long-term cognitive decline. Recent work in animal models is beginning to shed light on the interactions between systemic inflammation and CNS pathology in these acute exacerbations of dementia. This review will assess the role of prostaglandin synthesis in the memory impairments observed in dementia and delirium and will examine the relative contribution of amyloid, synaptic and neuronal loss. We will also discuss how understanding the role of inflammatory mediators in delirious episodes will have major implications for ameliorating the rate of decline in the demented population
Ocean current connectivity propelling the secondary spread of a marine invasive comb jelly across western Eurasia
Publication history: Accepted - 15 February 2018; Published - 16 May 2018.Aim: Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further
distribution after the initial establishment of non-native species remain largely unresolved, especially
in marine systems. Ocean currents can be a major driver governing range occupancy, but this has
not been accounted for in most invasion ecology studies so far. We investigate how well initial
establishment areas are interconnected to later occupancy regions to test for the potential role of
ocean currents driving secondary spread dynamics in order to infer invasion corridors and the
source–sink dynamics of a non-native holoplanktonic biological probe species on a continental scale.
Location: Western Eurasia.
Time period: 1980s–2016.
Major taxa studied: ‘Comb jelly’ Mnemiopsis leidyi.
Methods: Based on 12,400 geo-referenced occurrence data, we reconstruct the invasion history
of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the
temporal and spatial spread dynamics with large-scale connectivity patterns via ocean currents.
Additionally, genetic markers are used to test the predicted connectivity between subpopulations.
Results: Ocean currents can explain secondary spread dynamics, matching observed range expansions
and the timing of first occurrence of our holoplanktonic non-native biological probe species,
leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year-round populations in highly interconnected regions can re-seed genotypes over
large distances after local extinctions.
Main conclusions: Although the release of ballast water from container ships may contribute to
the dispersal of non-native species, our results highlight the importance of ocean currents driving
secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for
secondary spread dynamics on a continental scale. Invasion risk assessments should consider
large-scale connectivity patterns and the potential source regions of non-native marine species.Danish Council for Independent Research;
Grant/Award Number: DFF-1325-00102B;
FP7 People: Marie-Curie Actions,
Grant/Award Number: MOBILEX, DFF -
1325-00025; EU, BONUS, BMBF, Grant/
Award Number: 03F0682; Excellence
Cluster “Future Ocean”, Grant/Award
Number: CP153
A blood atlas of COVID-19 defines hallmarks of disease severity and specificity.
Treatment of severe COVID-19 is currently limited by clinical heterogeneity and incomplete description of specific immune biomarkers. We present here a comprehensive multi-omic blood atlas for patients with varying COVID-19 severity in an integrated comparison with influenza and sepsis patients versus healthy volunteers. We identify immune signatures and correlates of host response. Hallmarks of disease severity involved cells, their inflammatory mediators and networks, including progenitor cells and specific myeloid and lymphocyte subsets, features of the immune repertoire, acute phase response, metabolism, and coagulation. Persisting immune activation involving AP-1/p38MAPK was a specific feature of COVID-19. The plasma proteome enabled sub-phenotyping into patient clusters, predictive of severity and outcome. Systems-based integrative analyses including tensor and matrix decomposition of all modalities revealed feature groupings linked with severity and specificity compared to influenza and sepsis. Our approach and blood atlas will support future drug development, clinical trial design, and personalized medicine approaches for COVID-19
Scyphozoan jellyfish provide short-term reproductive habitat for hyperiid amphipods in a temperate near-shore environment
Hyperiid amphipods (Order Amphipoda, Suborder Hyperiidea) are known to infest gelatinous zooplankton. However, the temporal backdrop to these associations is less clear, given that data are often gathered during discrete sampling events rather than over time. In general, hyperiids are considered to be pelagic: however, for individuals associated with metagenic jellyfishes in temperate shallow shelf seas, this may not always be the case, as the majority of their gelatinous hosts are present in the water column from spring to the onset of autumn. Here, we explored the temporal patterns of colonisation and overall duration of the association between Hyperia galba and 3 scyphozoan jellyfish species (Aurelia aurita, Cyanea capillata and C. lamarckii) in a temperate coastal system (Strangford Lough, Northern Ireland) during 2010 and 2012. Concomitantly, we used carbon and nitrogen stable isotope ratios to examine whether hyperiid infestation represented a permanent association with their host or was part of a more complex life history. We found that jellyfish were colonised by H. galba ca. 2 mo after they are first observed in the lough and that H. galba reached 100% prevalence in the different jellyfish species shortly before the medusae of each species disappeared from the water column. It is possible that some jellyfish overwintered in deeper water, prolonging the association between H. galba and their hosts. However, all the medusae sampled during the spring and early summer (whether they were newly emerged or had overwintered from the previous season) were not infected with hyperiids, suggesting that such behaviour was uncommon or that individuals had become dissociated from their host during the winter. Further evidence of temporary association came from stable isotope data, where δ13C and δ15N isotope ratios were indicative of feeding outside of their host prior to jellyfish colonisation. In combination, these findings suggest alternating habitat associations for H. galba, with the amphipods spending the majority of the year outside of the 3 scyphozoan species considered here