scholarly journals Snowflake morays, Echidna nebulosa, exhibit similar feeding kinematics in terrestrial and aquatic treatments

2021 ◽  
Author(s):  
Rita S. Mehta ◽  
Kyle R. Donohoe
Keyword(s):  
Marine Environment ◽  
Aquatic Environment ◽  
Body Plan ◽  
Terrestrial Environment ◽  
Feeding Kinematics ◽  
Pharyngeal Jaws ◽  
Pharyngeal Jaw

Some species of durophagous moray eels (Muraenidae) have been documented emerging from the marine environment to capture intertidal crabs but how they consume prey out of water is unknown. Here we trained snowflake morays, Echidna nebulosa, to undulate out of the aquatic environment to feed on land. On land, snowflake morays remove prey from the substrate by biting and swallow prey using pharyngeal jaw enabled transport. Although snowflake morays exhibit smaller jaw rotation angles on land when apprehending their prey, transport kinematics involving dorso-ventral flexion of the head to protract the pharyngeal jaws and overall feeding times did not differ between terrestrial and aquatic treatments. We suggest that their elongate body plan, ability to rotate their heads in the dorsoventral and lateral directions, and extreme pharyngeal movements, all contribute to the ability of durophagous morays to feed in the terrestrial environment.

scholarly journals Palynology of the dinosaur beds of Tendaguru (Tanzania) — preliminary results

Fossil Record ◽  
1999 ◽  
Vol 2 (1) ◽  
pp. 171-183 ◽  
Author(s):  
E. Schrank
Keyword(s):  
Marine Environment ◽  
Aquatic Environment ◽  
Freshwater Algae ◽  
Preliminary Results ◽  
Rare Elements ◽  
Palynological Assemblages ◽  
Terrestrial Source ◽  
Marine Influence ◽  
Abundant Element ◽  
Angiosperm Pollen

The Tendaguru Beds, southeastern Tanzania, have yielded two palynological assemblages of Kimmeridgian to Tithonian age: (1) the <i>Anapiculatisporites-Densoisporites-Trisaccites</i> assemblage from the Middle Saurian Beds and (2) the <i>Barbatacysta-Pareodinia</i> assemblage from the overlying <i>Smeei</i> Beds. A third assemblage with <i>Rhizophagites</i> and rare angiosperm pollen from the Upper Saurian Beds is contaminated by recent and subrecent material. <br><br> The <i>Anapiculatisporites-Densoisporites-Trisaccites</i> assemblage is characterized by the presence of freshwater algae (<i>Ovoidites</i>), pteridopyhtic-bryophytic spores and gymnosperm (conifer) pollen, with <i>Classopollis</i> as the most abundant element. Among the rare elements of this assemblage is the questionable dinoflagellate <i>Mendicodinium</i>? <i>quadratum</i>, possibly a Kimmeridgian-Tithonian marker. The miospores show palaeobiogeographic links to Southern Gondwana, especially Madagascar, Australia, Argentina and India. Deposition of this assemblage took place in an aquatic environment with strong palynological influx from a terrestrial source and questionable marine influence. <br><br> The <i>Barbatacysta-Pareodinia</i> assemblage contains a considerable number of dinoflagellates suggesting deposition in a marine environment. The terrestrially-derived miospores are impoverished and dominated by conifer pollen, while pteridophytic-bryophytic spores form a very subordinate element or are absent. <br><br> Die Tendaguru-Schichten, Südost-Tansania, haben zwei palynologische Assoziationen, deren Alter als Kimmeridge bis Tithon interpretiert wird, geliefert. Die <i>Anapiculatisporites-Densoisporites-Trisaccites</i>-Assoziation stammt aus den Mittleren Saurierschichten, und die <i>Barbatacysta-Pareodinia</i>-Assoziation charakterisiert die darüberlagernden <i>Smeei</i>-Schichten. Eine dritte Vergesellschaftung mit <i>Rhizophagites</i> und seltenen Angiospermen-Pollen aus den Oberen Saurierschichten ist durch rezentes bis subrezentes Material kontaminiert. <br><br> Die <i>Anapiculatisporites-Densoisporites-Trisaccites</i>-Assoziation ist durch die Anwesenheit von Süßwasser-Algen (<i>Ovoidites</i>), Pteridophyten-Bryophyten-Sporen und Gymnospermen-Pollen (Koniferen) gekennzeichnet mit <i>Classopollis</i> als dem häufigsten Element. Zu den seltenen Elementen dieser Assoziation gehört der fragliche Dinoflagellat <i>Mendicodinium</i>? <i>quadratum</i>, der möglicherweise als leitend für das Kimmeridge-Tithon angesehen werden kann. Die Miosporen zeigen paläobiogeographische Verbindungen nach Südgondwana, besonders nach Madagaskar, Australien, Argentinien und Indien. Das Ablagerungsmilieu dieser Assoziation war aquatisch mit starker Zufuhr von terrigenem Material, während mariner Einfluß fraglich ist. <br><br> Die Dinoflagellaten-führende <i>Barbatacysta-Pareodinia</i>-Assoziation wurde in einem marinen Milieu gebildet, in dem die Zufuhr terrigener Palynomorphe reduziert und im wesentlichen auf Koniferen-Pollen beschränkt war, während Pteridophyten-Bryophyten-Sporen nur sehr untergeordnet vorkommen oder ganz fehlen. <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.1999.4860020113" target="_blank">10.1002/mmng.1999.4860020113</a>

scholarly journals The cichlid oral and pharyngeal jaws are evolutionarily and genetically coupled

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Andrew J. Conith ◽  
R. Craig Albertson
Keyword(s):  
Prey Capture ◽  
Phenotypic Change ◽  
Functional Constraints ◽  
East African ◽  
Genetic Level ◽  
Evolutionary Success ◽  
African Rift ◽  
Pharyngeal Jaws ◽  
African Cichlids ◽  
Pharyngeal Jaw

AbstractEvolutionary constraints may significantly bias phenotypic change, while “breaking” from such constraints can lead to expanded ecological opportunity. Ray-finned fishes have broken functional constraints by developing two jaws (oral-pharyngeal), decoupling prey capture (oral jaw) from processing (pharyngeal jaw). It is hypothesized that the oral and pharyngeal jaws represent independent evolutionary modules and this facilitated diversification in feeding architectures. Here we test this hypothesis in African cichlids. Contrary to our expectation, we find integration between jaws at multiple evolutionary levels. Next, we document integration at the genetic level, and identify a candidate gene, smad7, within a pleiotropic locus for oral and pharyngeal jaw shape that exhibits correlated expression between the two tissues. Collectively, our data show that African cichlid evolutionary success has occurred within the context of a coupled jaw system, an attribute that may be driving adaptive evolution in this iconic group by facilitating rapid shifts between foraging habitats, providing an advantage in a stochastic environment such as the East African Rift-Valley.

Understanding Effects of OAE 2 in the Marginal-marine Environment: A Multi-proxy approach from Bagh Beds, Western India

2020 ◽  
Author(s):  
Bikash Ranjan Sahu ◽  
Sohom Roy ◽  
Prasanta Sanyal
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Marine Environment ◽  
Nutrient Dynamics ◽  
Isotope Composition ◽  
Western India ◽  
Organic Carbon Content ◽  
Terrestrial Environment ◽  
Shallow Marine ◽  
Carbon Reservoir

&lt;p&gt;The Cenomanian-Turonian (C/T) Oceanic Anoxic Event 2 (OAE 2) at ~94 million years ago was characterized by severe depletion in marine water oxygen levels and extreme perturbations in the carbon cycle at a global scale that lasted for 5 to 6-million years. However, wealth of the data comes mainly from deep marine records, hugely limiting our understanding on the contemporaneous terrestrial environmental conditions. Here, we present major and trace element concentrations, carbon isotope composition of carbonates (&amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb&lt;/sub&gt;) and organic matter (&amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;bulk&lt;/sub&gt;), organic carbon content (TOC), and biomarker composition from a ~20 m thick well-preserved shallow marine sequence from the Bagh Beds in Uchad, western India in order to investigate the nutrient dynamics, productivity variations and carbon reservoir perturbations in shallow marine as well as in terrestrial environment. Based on litho-stratigraphy, the Uchad section is divided into Lower Cenomanian, Turonian and Upper Coniacian units. A total of ~5&amp;#8240; increase in the &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb&lt;/sub&gt; and 0.07% in TOC values and a sharp 1.7&amp;#8240; decrease in the &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;bulk &lt;/sub&gt;values in Lower Cenomanian suggest large changes in organic carbon recycling before the advent of OAE 2. Higher terrigenous influx and micro-nutrient supply in the lower parts is also suggested from relatively higher concentrations of Al, Ti, Th, Fe, Zn, Ni and K, although their concentrations decrease rapidly above the C/T boundary. Significant correlation observed between &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;bulk&lt;/sub&gt; and &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb&lt;/sub&gt; (r=0.51, p=0.03) supports an authigenic organic matter production in the shallow marine environment. However, minor enrichments in redox-sensitive elements like Mo, V and U observed above the C/T boundary probably suggest that the shallow marine region was relatively less affected during the initial anoxic phases. Lack of correlation between redox-sensitive elements and Al or Ti concentrations (r &lt;0.12) suggest that there is minimal influence of detrital supply on recycling of U, V and Mo. Interestingly, Lower Turonian units show large positive excursions in redox-sensitive elements as well as increases in U/Th, Ni/Co and V/(V+Ni) values, which are succeeded by a major decrease in &amp;#948;&lt;sup&gt;13&lt;/sup&gt;C&lt;sub&gt;carb &lt;/sub&gt;values (7.6&amp;#8240;) and increase in the TOC values by 0.15%, thereby suggesting occurrence of a more expanded episode of anoxia in Lower Turonian that perturbed the shallow marine carbon reservoir. Ba/Al ratios are variable throughout the section, although large positive spikes preceding and succeeding the anoxic phases suggest a causal link between organic matter productivity and anoxia.&lt;/p&gt;

Exploring the Growing Role of Terrestrial Carbon Across North Atlantic Fjords

2020 ◽  
Author(s):  
Craig Smeaton ◽  
William Austin
Keyword(s):  
Organic Carbon ◽  
Marine Environment ◽  
North Atlantic ◽  
Planetary Science ◽  
Terrestrial Environment ◽  
Carbon Burial ◽  
Organic Carbon Burial ◽  
Fjord Sediments

&lt;p&gt;Fjords are recognized as globally significant hotspots for the burial (Smith et al., 2015) and long-term storage (Smeaton et al., 2017) of marine and terrestrially derived organic carbon (OC). By trapping and locking away OC over geological timescales, fjord sediments provide a potentially important yet largely overlooked climate regulation service. The proximity of fjords to the terrestrial environment in combination with their geomorphology and hydrography results in the fjordic sediments being subsidized with organic carbon (OC) from the terrestrial environment. This terrestrial OC (OC&lt;sub&gt;terr&lt;/sub&gt;) transferred to the marine environment has traditionally be considered lost to the atmosphere in the form of CO&lt;sub&gt;2&lt;/sub&gt; in most carbon (C) accounting schemes yet globally it is estimated that 55% of OC trapped in fjord sediments is derived from terrestrial sources (Cui et al., 2016). So is this terrestrial OC truly lost? Here, we estimate the quantity of OC&lt;sub&gt;terr&lt;/sub&gt; held within North Atlantic fjords with the aim of better understanding the recent and long-term role of the terrestrial environment in the evolution of these globally significant sedimentary OC stores. By understanding this subsidy of OC from the terrestrial to the marine environment we can take the first steps in quantifying the terrestrial OC stored in fjords and the wider coastal marine environment.&lt;/p&gt;&lt;p&gt;Cui, X., Bianchi, T.S., Savage, C. and Smith, R.W., 2016. Organic carbon burial in fjords: Terrestrial versus marine inputs.&amp;#160;&lt;em&gt;Earth and Planetary Science Letters&lt;/em&gt;,&amp;#160;&lt;em&gt;451&lt;/em&gt;, pp.41-50.&lt;/p&gt;&lt;p&gt;Smeaton, C., Austin, W.E., Davies, A., Baltzer, A., Howe, J.A. and Baxter, J.M., 2017. Scotland's forgotten carbon: a national assessment of mid-latitude fjord sedimentary stocks.&amp;#160;&lt;em&gt;Biogeosciences&lt;/em&gt;.&lt;/p&gt;&lt;p&gt;Smith, R.W., Bianchi, T.S., Allison, M., Savage, C. and Galy, V., 2015. High rates of organic carbon burial in fjord sediments globally.&amp;#160;&lt;em&gt;Nature Geoscience&lt;/em&gt;,&amp;#160;&lt;em&gt;8&lt;/em&gt;(6), p.450.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;

scholarly journals Design and Modelling of an Amphibious Spherical Robot Attached with Assistant Fins

2021 ◽  
Vol 11 (9) ◽  
pp. 3739
Author(s):  
Xing Chi ◽  
Qiang Zhan
Keyword(s):  
Spherical Shell ◽  
Aquatic Environment ◽  
Adaptive Design ◽  
Rolling Motion ◽  
Spherical Robot ◽  
Terrestrial Environment ◽  
Aquatic Locomotion ◽  
Innovative Solution ◽  
Novel Concept ◽  
Security Surveillance

Mobile robots that can survive in unstructured wildernesses is essential in many applications such as environment detecting and security surveillance. In many of these applications, it is highly desirable that the robot can adapt robustly to both terrestrial environment and aquatic environment, and translocate swiftly between various environments. A novel concept of amphibious spherical robot with fins is proposed in this paper, capable of both terrestrial locomotion and aquatic locomotion. Unlike the traditional amphibious robots, whose motions are commonly induced by propellers, legs or snake-like tandem joints, the proposed amphibious spherical robot utilizes the rolling motion of a spherical shell as the principal locomotion mode in the aquatic environment. Moreover, spinning motion of the spherical shell is used to steer the spherical robot efficiently and agilely; several fins are attached to the outer spherical shell as an assistance to the rolling motion. These two motion modes, rolling and spinning, can be used unchangeably in the terrestrial environment, leading to a compact and highly adaptive design of the robot. The work introduced in this paper brings in an innovative solution for the design of an amphibious robot.

scholarly journals AMR Escherichia coli and its temporal and spatial variability within the aquatic environment

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Amelia Odell ◽  
Paul Eady ◽  
Ronald Dixon
Keyword(s):  
Escherichia Coli ◽  
Aquatic Environment ◽  
Spatial Dynamics ◽  
Pcr Analysis ◽  
Terrestrial Environment ◽  
E Coli ◽  
Wwtp Effluent ◽  
Temporal And Spatial Variability ◽  
Temporal And Spatial ◽  
Genotypic Identification

Phenotypic and genotypic identification methods have been used to determine the temporal and spatial dynamics of AMR-Escherichia coli in a mainly rural watercourse that receives WWTP-effluent compared to a parallel river which does not. We aimed to investigate the incidence of plasmid-mediated mcr-1and β-lactamase-genes in E. coli recovered from both water and Asellus aquaticus samples throughout two-calendar-years. Samples of the water and A. aquaticus were recovered from the relevant locations each month. CHROMagar ESBL agar was used throughout to isolate and identify ESBL-E. coli. The presence of AMR-genes was confirmed using the ‘BSAC’ antibiotic-disk-synergy method and PCR analysis to confirm the presence of mcr-1and ESBL-genes. The CHROMagar ESBL agar was found to be 99.7% (n=578) accurate when confirmed with a PCR analysis of the ESBL-genes. Seventy-six-point-six percent (n=449) of the isolated ESBL-E. coli were correctly identified as ESBL-producing organisms using the ‘BSAC’ method. Interestingly 61.9% (n=358) of the ESBL-E. coli were also found to carry the mcr-1 gene. Our data shows that AMR levels were highest at the WWTP-effluent throughout the two-years for both water and A. aquaticus samples. The incidence of AMR-E. coli 1km downstream of the effluent discharge was equivalent to the parallel river sites, suggesting that the dispersal of AMR from the WWTP-effluent is limited, although AMR-E. coli were found in relatively high numbers at the WWTP-effluent. We argue that the presence of AMR in the freshwater invertebrate A. aquaticus could represent an important route by which AMR can spread from the aquatic environment to the terrestrial environment.

scholarly journals Improving functional and motor capacity through means/resources and methods specific to acvatic activities

2021 ◽  
Vol 12 (Vol.12, no.1) ◽  
pp. 27-30
Author(s):  
Iustina CONDURACHE ◽  
Marius TURNEA ◽  
Mariana ROTARIU
Keyword(s):  
Physical Exercise ◽  
Aquatic Environment ◽  
High Amplitude ◽  
The Body ◽  
Entire Body ◽  
Terrestrial Environment ◽  
Precise Control ◽  
Beneficial Effects ◽  
Muscle Groups ◽  
General Physical

Introduction. Exercise programs in the aquatic environment have as their main objective the improvement and maintenance of physical capacity/ capability, these being in continuous development and diversification. Water exercise amplifies the effects of general physical exercise, by allowing a more precise control over the movement of each body segment and of the body as a whole. The aquatic environment offers a number of beneficial effects compared to ones offered by the terrestrial environment. The benefits obtained through the aquatic activities are fundamental and are reflected throughout the entire body including both motor, functional and aesthetic level. Material and method. The objective of this study is represented by the identification of new forms of physical exercise that will increase the effort’s capacity. In order to achieve this goal, several methodological requirements were met, such as: successive engagement of the joints and muscle groups in effort (starting with the neck’s muscles, shoulders, arms, torso and legs, simultaneously with scapular-humeral joints, spine and coxo-femoral joints and legs), the gradually usage of exercises, starting with the most basic and then increasing the complexity of the exercises, the usage of the accessible exercises in the beginning of the training, executed with high amplitude and reduced speed, focusing on the correctness of the execution, the selection and the adequate/ appropriately usage of the initial positions according to the subject’s particularities and the shape/form of the exercise, the optimal control of the effort, achieved through a number of iterations, optimal execution time and breaks, the sets of general physical exercises will consist of sets of 8-12 exercises/reps, the principle of symmetry in the execution of the exercises has to be respected, the continuity of practicing a set of exercises for 6 to 8 consecutive lessons, the recommended work method is fragmented-imitative, efficiently combining the explication with the demonstration, the number of repetitions and the movement’s correction. Results and discussions. Analyzing results obtained after the evaluation, we have noticed significant growth in the functional and motor capacities. Conclusions. The systematization of water activities on objective criteria effectively contributes to their knowledge, while allowing them to be included in the spectrum of recreational, sporting, relaxing or therapeutic activities. Keywords: acvatic activities, physical exercise, evaluations,

scholarly journals Improving functional and motor capacity through means/resources and methods specific to acvatic activities

2021 ◽  
pp. 314-317
Author(s):  
Iustina CONDURECHE ◽  
Luminița CONFEDERAT ◽  
Mariana ROTARIU ◽  
Marius TURNEA
Keyword(s):  
Physical Exercise ◽  
Aquatic Environment ◽  
High Amplitude ◽  
The Body ◽  
Entire Body ◽  
Terrestrial Environment ◽  
Precise Control ◽  
Beneficial Effects ◽  
Muscle Groups ◽  
General Physical

Introduction. Exercise programs in the aquatic environment have as their main objective the improvement and maintenance of physical capacity/ capability, these being in continuous development and diversification. Water exercise amplifies the effects of general physical exercise, by allowing a more precise control over the movement of each body segment and of the body as a whole. The aquatic environment offers a number of beneficial effects compared to ones offered by the terrestrial environment. The benefits obtained through the aquatic activities are fundamental and are reflected throughout the entire body including both motor, functional and aesthetic level. Material and method. The objective of this study is represented by the identification of new forms of physical exercise that will increase the motor’s capacity. In order to achieve this goal, several methodological requirements were met, such as: successive engagement of the joints and muscle groups in effort (starting with the neck’s muscles, shoulders, arms, torso and legs, simultaneously with scapular-humeral joints, spine and coxo-femoral joints and legs), the gradually usage of exercises, starting with the most basic and then increasing the complexity of the exercises, the usage of the accessible exercises in the beginning of the training, executed with high amplitude and reduced speed, focusing on the correctness of the execution, the selection and the adequate/ appropriately usage of the initial positions according to the subject’s particularities and the shape/form of the exercise, the optimal control of the effort, achieved through a number of iterations, optimal execution time and breaks, the sets of general physical exercises will consist of sets of 8-12 exercises/reps, the principle of symmetry in the execution of the exercises has to be respected, the continuity of practicing a set of exercises for 6 to 8 consecutive lessons, the recommended work method is fragmented-imitative, efficiently combining the explication with the demonstration, the number of repetitions and the movement’s correction. Results and discussions. Analyzing results obtained after the evaluation, we have noticed significant growth in the functional and motor capacities. Conclusions. The systematization of water activities on objective criteria effectively contributes to their knowledge, while allowing them to be included in the spectrum of recreational, sporting, relaxing or therapeutic activities. Keywords: acvatic activities, physical exercise, evaluations,

scholarly journals OIL SPILL IN A MARINE ENVIRONMENT: REQUIREMENTS FOLLOWING AN OFFSHORE OIL SPILL

2021 ◽  
Vol 36 (4) ◽  
pp. 1-9
Author(s):  
Suresh Kumar Govindarajan ◽  
Avanish Mishra ◽  
Abhishek Kumar
Keyword(s):  
Oil Spill ◽  
Marine Environment ◽  
Oil Spills ◽  
Daily Basis ◽  
Modern World ◽  
Terrestrial Environment ◽  
Almost Everywhere ◽  
Detailed List ◽  
Offshore Oil ◽  
Spilled Oil

The global lifestyle of this modern world has become more dependent on petroleum-based products, whose applications are involved almost everywhere. Since a large quantity of oil is being used on a daily basis, the spilling of oil by various means during its storage and transportation has become inevitable. This work focuses on the spilling of oil in a marine environment, generally referred to as an offshore oil spill, in contrast to an onshore oil spill associated with a terrestrial environment. These oil spills not only devastate the natural resources and unsettle the economy, they also jeopardize marine life, as well as human health. The remediation of an oil spill remains very challenging, when the disaster is associated with a large aerial extent. In this context, a sound understanding is required on the origin, seeping, composition and properties of the spilled oil in order to better monitor the spreading of the oil spill. In this manuscript, a detailed list of fundamental queries, which will be required to be addressed at the instance of an oil spill has been deduced, which will be extremely useful for the oil spill respondents as there are no previous studies that exclusively provide the type and nature of data required to be collected, immediately following an oil spill. Furthermore, this manuscript has deduced a list of sensitive and essential plots that will be required in order to analyse and forecast the spreading of an oil spill. An essence of weathering and its associated movement of oil spill has been included.

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