Floating nurseries? Scyphozoan jellyfish, their food and their rich symbiotic fauna in a tropical estuary

Background The anthropogenic modification of trophic pathways is seemingly prompting the increase of jellyfish populations at the expense of planktivorous fishes. However, gross generalizations are often made because the most basic aspects of trophic ecology and the diverse interactions of jellyfish with fishes remain poorly described. Here we inquire on the dynamics of food consumption of the medusoid stage of the scyphozoan jellyfish Stomolophus meleagris and characterize the traits and diversity of its symbiotic community. Methods S. meleagris and their associated fauna were sampled in surface waters between November 2015 and April 2017 in Málaga Bay, an estuarine system at the Colombian Pacific. Stomach contents of medusae were examined and changes in prey composition and abundance over time analysed using a multivariate approach. The associated fauna was identified and the relationship between the size of medusae and the size those organisms tested using least-square fitting procedures. Results The presence of S. meleagris medusa in surface waters was seasonal. The gut contents analysis revealed that algae, copepods and fish early life stages were the more abundant items, and PERMANOVA analysis showed that the diet differed within the seasons (P(perm) = 0.001) but not between seasons (P(perm) = 0.134). The majority of the collected medusae (50.4%) were associated with individuals of 11 symbiotic species, 95.3% of them fishes, 3.1% crustaceans and 1.6% molluscs. Therefore, this study reports 10 previously unknown associations. The bell diameter of S. meleagris was positively related to the body sizes of their symbionts. However, a stronger fit was observed when the size relationship between S. meleagris and the fish Hemicaranx zelotes was modelled. Discussion The occurrence of S. meleagris was highly seasonal, and the observed patterns of mean body size through the seasons suggested the arrival of adult medusae to the estuary from adjacent waters. The diet of S. meleagris in the study area showed differences with previous reports, chiefly because of the abundance of algae that are seemingly ingested but not digested. The low number of zooplanktonic items in gut contents suggest the contribution of alternative food sources not easily identifiable. The observed changes in the composition of food in the guts probably reflect seasonal changes in the availability of prey items. The regular pattern in the distribution of symbionts among medusae (a single symbiont per host) and the positive host-symbiont size relationship reflects antagonistic intraspecific and interspecific behaviour of the symbiont. This strongly suggest that medusa represent an “economically defendable resource” that potentially increases the survival and recruitment of the symbionts to the adult population. We argue that, if this outcome of the symbiotic association can be proven, scyphozoan jellyfish can be regarded as floating nurseries.

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Floating nurseries? Scyphozoan jellyfish, their food and their rich symbiotic fauna in a tropical estuary

10.7287/peerj.preprints.26497 ◽

2018 ◽

Author(s):

José M Riascos ◽

Willington Aguirre ◽

Charlotte Hopfe ◽

Diego Morales ◽

Ángela Navarrete ◽

...

Keyword(s):

Surface Waters ◽

The Body ◽

Food Sources ◽

Gut Contents ◽

Estuarine System ◽

Symbiotic Association ◽

Bell Diameter ◽

Associated Fauna ◽

Size Relationship ◽

Scyphozoan Jellyfish

The anthropogenic modification of basal trophic pathways is seemingly prompting the increase of jellyfish populations at the expense of planktivorous fishes. However, gross generalizations are often made because the most basic aspects of trophic ecology and the diverse interactions of jellyfish with fishes remain poorly described. Here we inquire on the dynamics of food consumption of the medusoid stage of the scyphozoan jellyfish Stomolophus meleagris and characterize the traits and diversity of its symbiotic community. S. meleagris and their associated fauna were sampled in surface waters between November 2015 and April 2017 in Málaga Bay, an estuarine system at the Colombian Pacific. Stomach contents of medusae were examined and changes in prey composition and abundance over time analysed using a multivariate approach. The associated fauna was identified and the relationship between the size of medusae and the size their symbionts tested using least-square fitting procedures. The presence of S. meleagris medusa in surface waters was seasonal. The gut contents analysis revealed that algae, copepods and fish early life stages were the more abundant items, and PERMANOVA analysis showed that the diet differed within the seasons (P(perm)=0.001) but not between seasons (P(perm)=0.134). The majority of the collected medusae (50.4 %) were associated to individuals of 11 symbiotic species, 95.3% of them fishes, 3.1% crustaceans and 1.6% molluscs. Thereby, this study reports 10 previously unknown associations. The bell diameter of S. meleagris was positively related to the body sizes of their symbionts. However, a stronger fit was observed when the size relationship between S. meleagris and the fish Hemicaranx zelotes was modelled. The ocurrence of S. meleagris was highly seasonal, and the observed patterns of mean body size through the seasons suggested the arrival of adult medusae to the estuary from adjacent waters. The diet of S. meleagris in the study area showed differences with previous reports, chiefly because of the consistent abundance of algae that are seemingly ingested but not digested. The low number of zooplanktonic items in gut contents suggest the contribution of alternative food sources not easily identifiable. The observed changes in the composition of food in the guts probably reflect seasonal changes in the availability of prey items. The regular pattern in the distribution of symbionts among medusae (a single symbiont per host) and the positive host-symbiont size relationship reflects antagonistic intraspecific and interspecific behaviour of the symbiont. This strongly suggest that medusa represent an “economically defendable resource” that potentially increases the survival and recruitment of the symbionts to the adult population. We argue that, if this outcome of the symbiotic association can be proven, scyphozoan jellyfish can be regarded as floating nurseries.

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Floating nurseries? Scyphozoan jellyfish, their food and their rich symbiotic fauna in a tropical estuary

10.7287/peerj.preprints.26497v1 ◽

2018 ◽

Author(s):

José M Riascos ◽

Willington Aguirre ◽

Charlotte Hopfe ◽

Diego Morales ◽

Ángela Navarrete ◽

...

Keyword(s):

Surface Waters ◽

The Body ◽

Food Sources ◽

Gut Contents ◽

Estuarine System ◽

Symbiotic Association ◽

Bell Diameter ◽

Associated Fauna ◽

Size Relationship ◽

Scyphozoan Jellyfish

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Feeding activity and diet composition of round goby (Neogobius melanostomus, Pallas 1814) in the coastal waters of SE Baltic Sea

Oceanological and Hydrobiological Studies ◽

10.1515/ohs-2015-0048 ◽

2015 ◽

Vol 44 (4) ◽

Cited By ~ 7

Author(s):

Artūras Skabeikis ◽

Jūratė Lesutienė

Keyword(s):

Baltic Sea ◽

Coastal Waters ◽

Diet Composition ◽

Feeding Activity ◽

Macoma Balthica ◽

Round Goby ◽

Benthic Fauna ◽

Neogobius Melanostomus ◽

The Body ◽

Gut Contents

AbstractFeeding activity and diet composition of round goby were investigated in the south-eastern Baltic Sea, the Lithuanian coastal waters during May-October 2012 in order to determine main feeding objects and seasonal periods when native fauna could be most affected by predation of this highly invasive species. In total, prey represented by 18 taxa was found in the gut contents of dissected fish. Feeding activity of round goby varied depending on the body size, sex and stage of the reproduction period. The gut contents of < 50 mm specimens were dominated by zooplanktonic and meiobenthic organisms, whereas larger individuals (50–99 mm) shifted to amphipods and mollusks. Individuals of the intermediate 100-200 mm length had a variable diet, changing depending on the season; in spring they mostly preyed on Macoma balthica, in summer − on polychaetes, while in autumn the contribution of Mytilus trossulus and fish considerably increased in their diet. Diet composition of individuals ≥ 200 mm was relatively constant in the course of the study with substantial preference to M. balthica. These findings imply that benthic fauna, particularly a newly settled generation of epibenthic mollusks in autumn is under strong predatory pressure of the round goby.

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Pretty Picky for a Generalist: Impacts of Toxicity and Nutritional Quality on Mantid Prey Processing

Environmental Entomology ◽

10.1093/ee/nvx038 ◽

2017 ◽

Vol 46 (3) ◽

pp. 626-632 ◽

Cited By ~ 2

Author(s):

Jamie L. Rafter ◽

Justin F. Vendettuoli ◽

Liahna Gonda-King ◽

Daniel Niesen ◽

Navindra P. Seeram ◽

...

Keyword(s):

C:N Ratio ◽

Danaus Plexippus ◽

Monarch Butterfly ◽

The Body ◽

Gut Contents ◽

Corn Borers ◽

Body Tissues ◽

Heterogeneous Quality ◽

Behavioral Trials

Abstract Prey have evolved a number of defenses against predation, and predators have developed means of countering these protective measures. Although caterpillars of the monarch butterfly,Danaus plexippus L., are defended by cardenolides sequestered from their host plants, the Chinese mantidTenodera sinensis Saussure guts the caterpillar before consuming the rest of the body. We hypothesized that this gutting behavior might be driven by the heterogeneous quality of prey tissue with respect to toxicity and/or nutrients. We conducted behavioral trials in which mantids were offered cardenolide-containing and cardenolide-freeD. plexippus caterpillars and butterflies. In addition, we fed mantids starved and unstarvedD. plexippus caterpillars from each cardenolide treatment and nontoxicOstrinia nubilalis Hübner caterpillars. These trials were coupled with elemental analysis of the gut and body tissues of bothD. plexippus caterpillars and corn borers. Cardenolides did not affect mantid behavior: mantids gutted both cardenolide-containing and cardenolide-free caterpillars. In contrast, mantids consumed bothO. nubilalis and starvedD. plexippus caterpillars entirely.Danaus plexippus body tissue has a lower C:N ratio than their gut contents, whileO. nubilalis have similar ratios; gutting may reflect the mantid’s ability to regulate nutrient uptake. Our results suggest that post-capture prey processing by mantids is likely driven by a sophisticated assessment of resource quality.

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Geochemistry of intertidal sediment pore waters from the industrialized Santos-Cubatão Estuarine System, SE Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652012005000021 ◽

2012 ◽

Vol 84 (2) ◽

pp. 427-442 ◽

Cited By ~ 6

Author(s):

Winston F.O. Gonçalves ◽

Wanilson Luiz-Silva ◽

Wilson Machado ◽

Erico C. Nizoli ◽

Ricardo E. Santelli

Keyword(s):

Surface Water ◽

Pore Water ◽

Surface Waters ◽

Water Concentration ◽

Point Sources ◽

Intertidal Sediment ◽

Estuarine System ◽

Pore Waters ◽

Geochemical Composition ◽

Se Brazil

The geochemical composition of sediment pore water was investigated in comparison with the composition of sediment particles and surface water in an estuary within one of the most industrialized areas in Latin America (Santos-Cubatão estuarine system, SE Brazil). Pore and surface waters presented anomalously high levels of F-, NH4+, Fe, Mn and P due to two industrial point sources. In the summer, when SO4(2-)/Cl- ratios suggested an enhanced sulfate reduction, the higher dissolved levels observed in pore waters for some metals (e.g., Cu and Ni) were attributed to reductive dissolution of oxidized phases. Results evidenced that the risks of surface water concentration increase due to diffusion or advection from pore water are probably dependent on coupled influences of tidal pumping and groundwater inputs.

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Contamination of food with cadmium and dioxins – influence on the human body

Pomeranian Journal of Life Sciences ◽

10.21164/pomjlifesci.598 ◽

2019 ◽

Vol 65 (3) ◽

Author(s):

Aleksandra Słojewska ◽

Izabela Gutowska

Keyword(s):

General Population ◽

Health Effects ◽

Human Body ◽

Bone Mineralization ◽

The Body ◽

Food Sources ◽

Hormonal Balance ◽

Small Doses ◽

Contaminated Food

Introduction: Food is a carrier of many pollutants nowadays. For cadmium and dioxins, it is the main source of these compounds in the general population. Hence, the aim of this work was to collect data on the health effects associated with exposure to cadmium and dioxins which get into the human body through food.Materials and methods: A literature review was conducted by searching the scientific Medline database (PubMed) and Google Scholar.Results: Health effects associated with a long-term exposure to low doses of cadmium and dioxins may be nonspecific and are rarely attributed to food sources. These may cause disorders affecting hormonal balance, kidney function, lipid metabolism, fertility, cognitive function, bone mineralization, and susceptibility to diseases and allergies. These compounds may also lead to cancer development.Conclusions: The general population faces the problem of longterm exposure to small doses of these substances due to their accumulation in the body, even if their amounts do not exceed the relevant standards. The health effects of this type of exposure may be significantly delayed and are not likely to be attributed to the consumption of contaminated food. Consumers wishing to reduce the amounts of these compounds delivered to the body should limit the consumption of grilled and smoked products, and should also opt for organic food.

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Effect of stingray (Hemitrygon akajei) foraging on a ghost shrimp population (Nihonotrypaea harmandi) on an intertidal sandflat, western Kyushu, Japan

Marine and Freshwater Research ◽

10.1071/mf19265 ◽

2020 ◽

Vol 71 (9) ◽

pp. 1128

Author(s):

Akio Tamaki ◽

Kazuyuki Harada ◽

Yoshinobu Sogawa ◽

Seiji Takeuchi

Keyword(s):

Spring Tide ◽

The Body ◽

Gut Contents ◽

Size Frequency Distribution ◽

Frequency Distributions ◽

Size Frequency ◽

Intertidal Sandflat ◽

Shrimp Density ◽

Feeding Bout ◽

Shrimp Population

Callianassid shrimp residing in deep burrows have large bioturbating effects on marine soft-bottom communities. A few predators that excavate deep pits could have substantial effects on shrimp populations, as well as knock-on effects. Processes and consequences of such effects on shrimp populations are poorly understood. On a 300-m-wide intertidal sandflat area between tide marks in western Kyushu between 1989 and 1994, shrimp population densities were stable, reaching >1300individualsm–2. Dasyatid stingray feeding pits reaching depths up to 20cm occurred abruptly in large numbers in 1994, after which shrimp densities decreased yearly to hundreds of individuals per square metre in 2001. The densities of ray feeding pits formed per day were monitored every or every other spring tide between 2000 and 2001. Schools of rays were enclosed during submerged times and their body sizes recorded alive to determine size-frequency distribution. The body-size frequency distributions of shrimp were compared among the gut contents of several rays, ray feeding pits and intact sandflat. Reductions in the shrimp density per ray feeding bout compared with the density on the intact sandflat were recorded. A model of daily predation at different seasonal rates was used to simulate the yearly change in shrimp density. The result was consistent with the actual change.

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The Role of Micronutrients to Support Immunity for COVID-19 Prevention

Revista Brasileira de Farmacognosia ◽

10.1007/s43450-021-00179-w ◽

2021 ◽

Author(s):

Mukhtar H. Ahmed ◽

Arez Hassan ◽

Judit Molnár

Keyword(s):

Immune System ◽

Healing Process ◽

Strong Relationship ◽

The Body ◽

World Health ◽

Disease Spread ◽

Food Sources ◽

Novel Coronavirus ◽

Health Organization ◽

The Impact

AbstractThe World Health Organization declared the novel coronavirus, named as SARS-CoV-2, as a global pandemic in early 2020 after the disease spread to more than 180 countries leading to tens of thousands of cases and many deaths within a couple of months. Consequently, this paper aims to summarize the evidence for the relationships between nutrition and the boosting of the immune system in the fight against the disease caused by SARS-CoV-2. This review, in particular, assesses the impact of vitamin and mineral supplements on the body’s defence mechanisms against SARS-CoV-2. The results revealed that there is a strong relationship between the ingestion of biological ingredients like vitamins C–E, and minerals such as zinc, and a reduction in the effects of coronavirus infection. These can be received from either nutrition rich food sources or from vitamin supplements. Furthermore, these macromolecules might have roles to play in boosting the immune response, in the healing process and the recovery time. Hence, we recommend that eating healthy foods rich in vitamins C–E with zinc and flavonoids could boost the immune system and consequently protect the body from serious infections. Graphical Abstract

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Fermentation Technology as a Driver of Human Brain Expansion

10.20944/preprints202010.0135.v1 ◽

2020 ◽

Author(s):

Katherine Bryant ◽

Christi Hansen ◽

Erin Hecht

Keyword(s):

Brain Size ◽

Explanatory Power ◽

The Body ◽

Food Sources ◽

Fermented Foods ◽

Concomitant Reduction ◽

Empirical Tests ◽

Thesis Statement ◽

Brain Expansion ◽

Fermentation Technology

Thesis Statement: The consumption of externally fermented foods acted as the initial metabolic trigger enabling hominid brain expansion. Because brain tissue is metabolically expensive, it is thought that the evolution of humans’ large brains was only possible through a concomitant reduction in the size of another expensive organ system, the gut. However, this gut reduction must have itself been made possible by dietary changes, the nature of which are still unclear. Here, we propose that the initial metabolic trigger of hominid brain expansion may have been the consumption of externally fermented foods. We define “external fermentation” as occurring outside the body, as opposed to the internal fermentation that occurs through the gut microbiome. This practice could have begun accidentally and with limited understanding, but over time, fermentation technologies may have become increasingly intentional, socially-transmitted, and culturally-reinforced. We detail the mechanisms by which external fermentation can mediate the evolution of increased brain size, as well as a reduction in gut size, by increasing the bioavailability of macro- and micronutrients while reducing digestive energy expenditure. Importantly, we calculate that the reduction in human gut size relative to modern apes is mainly due to a reduction in the colon, the site of internal fermentation. We also discuss the explanatory power of our hypothesis relative to others, including realistic plausibility in hominids with brains roughly the size of modern chimpanzees. Finally, we survey external fermentation practices across human cultures to demonstrate its viability across a huge range of environments, temperatures, and food sources. We close with suggestions for empirical tests.

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Metabarcoding malaise trap plant components enables monitoring the diversity of plant-insect interactions

10.1101/2021.12.21.473674 ◽

2021 ◽

Author(s):

Stephanie J. Swenson ◽

Lisa Eichler ◽

Thomas Hörren ◽

Gerlind U. C. Lehmann ◽

Martin Sorg ◽

...

Keyword(s):

Potential Method ◽

Rare Plants ◽

The Body ◽

Gut Contents ◽

Cultivated Plants ◽

Malaise Trap ◽

Food Material ◽

Dna Metabarcoding ◽

Abundance And Diversity ◽

Insect Interactions

The declines observed in insect abundance and diversity in the past decades has also been observed in plants, and these events are most certainly correlated. Rapid largescale biomonitoring of both plants and insects can help monitor these changes and inform decisions for land management and species protection. Malaise traps have been used for nearly 80 years for passive insect sampling of primarily flying insects, and when they enter these traps, they carry the fragments of the plants they have visited, either as plant fragments and pollen on the body surface, or as digested food material in gut contents. DNA metabarcoding is a potential method to identify these plant traces in the ethanol of the malaise bottles, which is not possible with traditional microscopy. Metabarcoding could offer more insight into what plants insects are directly interacting with at a given time, and allow for the detection of rare plants, and neophyte species visited by insects. This study, to our knowledge, is the first examination of DNA metabarcoding plant traces from Malaise trap samples, we examine 105 samples from 21 sites throughout Germany collected in a 2-week period in May of 2020. Here we report on the feasibility of sequencing these sample types, analysis of the resulting taxa, the usage of cultivated plants by insects near nature conservancy areas, and the detection of rare and neophyte species.

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