Morphology Of Organisms Research Articles

When Does Form Reflect Function? Acknowledging and Supporting Ecomorphological Assumptions.

Ecomorphology is the study of relationships between organismal morphology and ecology. As such, it is the only way to determine if morphometric data can be used as an informative proxy for ecological variables of interest. To achieve this goal, ecomorphology often depends on, or directly tests, assumptions about the nature of the relationships among morphology, performance, and ecology. We discuss three approaches to the study of ecomorphology: morphometry-driven, function-driven, and ecology-driven and study design choices inherent to each approach. We also identify 10 assumptions that underlie ecomorphological research: 4 of these are central to all ecomorphological studies and the remaining 6 are variably applicable to some of the specific approaches described above. We discuss how these assumptions may impact ecomorphological studies and affect the interpretation of their findings. We also point out some limitations of ecomorphological studies, and highlight some ways by which we can strengthen, validate, or eliminate systematic assumptions.

The break-up between Darwin and Haeckel.

In the course of the second half of the nineteenth century, following the publication of Darwin's On the Origin of Species (1859) and Haeckel's Generelle Morphologie der Organismen (1866) (General Morphology of Organisms), the two men interacted like comrades in arms, leading the theory of evolution to victory in the international arena. This relationship broke up during the early decades of the twentieth century. The cause was primarily political, not scientific, and was brought about by the nationalistic mobilization of scientists that accompanied WW I and the Russian Revolution. In the course of these military and political upheavals, national flags were wrapped around different approaches to evolutionary biology. Darwinian natural selection became Anglified, Haeckelian morphology was Germanified, and in the Soviet Union, a Marxist version of Darwinian theory took root. The process of break-up was further affected by the emergence of Nazi ideology.

Prepared for the future: A strong signal of evolution toward the adult benthic niche during the pelagic stage in Labrid fishes.

The morphology of organisms reflects a balance between their evolutionary history, functional demands, and biomechanical constraints imposed by the immediate environment. In many fish species, a marked shift in the selection regime is evident when pelagic larvae, which swim and feed in the open ocean, settle in their adult benthic habitat. This shift is particularly dramatic in coral-reef fishes, where the adult habitat is immensely complex. However, whether the adult trophic ecotype affects the morphology of early-life stages is unclear. We measured a suite of 26 functional-morphological traits in the head and body of larvae from an ontogenetic series of 16 labrid species. Using phylogenetic comparative methods, we reconstructed the location of adaptive peaks of larvae whose adults are associated with different trophic ecotypes. We found that the morphospace occupation in these larvae is largely driven by divergent adaptations to the adult benthic habitats. The disparity between adaptive peaks is achieved early and does not monotonically increase with size. Our findings thus refute the notion that larvae rapidly acquire the trophic-specific traits during a metamorphic period immediately prior to settlement. This early specialization might be due to the highly complex musculoskeletal system of the head that cannot be rapidly modified.

Individual Morphology and Habitat Structure Alter Social Interactions in a Range-Shifting Species

Ecosystem engineers that serve as foundation species shape the ecology and behavior of the species which depend on them. As species shift their geographic ranges into ecosystems they have not previously inhabited, it is important to understand how interactions with novel foundation species alter their behavior. By employing behavioral assays and morphological analyses, we examined how individual morphology and foundation species structure impact the ritualistic aggression behavior of the range shifting mangrove tree crab Aratus pisonii between its historic and colonized habitats. Structure of the foundation species of the colonized salt marsh ecosystem increases the incidence and risk of this behavior over the historic mangrove habitat, potentially negating benefits of ritualizing aggression. Further, docks within the salt marsh, which are structurally analogous to mangroves, mitigate some, but not all, of the increased costs of performing ritualized aggression. Crabs in the salt marsh also had relatively larger claws than conspecifics from the dock and mangrove habitats, which has implications for the risk and outcomes of ritualized interactions. These changes to morphology and behavior highlight the impacts that foundation species structure can have on the morphology, ecology, and behavior of organisms and the importance of studying these impacts in range shifting species.

The Incidence of Methicillin Resistance Staphylococcus aureus in Diabetic Septic Foot

Background: Foot infection is the most common problem in a person with diabetes. Infection in these patients is difficult to treat because these individuals have impaired microvascular supply, Which limits the access of phagocytic cell in the infected area and result in poor concentration of antibody in the infected tissue. Staphylococcus aureus is a major cause of potentially life-threatening infection which was acquired in the health care and community setting. These microorganisms have developed resistance against most classes of antibacterial agent as indicated by a dramatic increase in the number of healthcare-associated infection due to methicillin resistance S. aureus, which become endemic in hospitals worldwide. Methods: All collected samples were cultured directly on the blood and chocolate agar to primary isolation, then purified by several subcultures from a single well-isolated colony. Identification of isolated bacteria depends on gram reactions, organism morphology, colonial morphology in different media and biochemical tests-catalase test, coagulase test, DNase test, mannitol fermentation test, and VP test. The antimicrobial test was carried by disc diffusion method Kirby-Bauer method on Muller and Hinton media to several single antibiotic discs-Vancomycin, cloxacillin, Tobracillin, Ciprofloxacin, and Ceftriaxone. The inhibition zone was measured by ruler in millimeter the compared with incorporated chart. Results: A total of 50 diabetic patients with wound infection were including S. aureus n:20, 40% and other pathogens n:30,60%. Frequency of male was 43,86% while 7,14% were female. All patient were classified into two groups of age, one (35-55) with moderate frequency n:20, 40% and another age group (56-90) with the highest frequency n:30,60%. All isolated S. aureus were resisted cloxacillin while sensitive to vancomycin, 60% of them resist tobracillin 40% were sensitive and 10% resist ciprofloxacin 90% were sensitive, 25% were resisted ceftriaxone 75% were sensitive. Conclusion: MRSA is highly 40% prevalent among populations of S. aureus isolated from surgical site infection in Khartoum state. This study discusses the link between MRSA acquisition factors like age, sex, occupation, ethnicity, geographical location, hospitalization, antibiotic use, surgery and distinction community-acquired MRSA and hospital-acquired MRSA.

Automated morphometry toolbox for analysis of microscopic model organisms using simple bright-field imaging.

ABSTRACTModel organisms with compact genomes, such as yeast and Caenorhabditis elegans, are particularly useful for understanding organism growth and life/cell cycle. Organism morphology is a critical parameter to measure in monitoring growth and stage in the life cycle. However, manual measurements are both time consuming and potentially inaccurate, due to variations among users and user fatigue. In this paper we present an automated method to segment bright-field images of fission yeast, budding yeast, and C. elegans roundworm, reporting a wide range of morphometric parameters, such as length, width, eccentricity, and others. Comparisons between automated and manual methods on fission yeast reveal good correlation in size values, with the 95% confidence interval lying between −0.8 and +0.6 μm in cell length, similar to the 95% confidence interval between two manual users. In a head-to-head comparison with other published algorithms on multiple datasets, our method achieves more accurate and robust results with substantially less computation time. We demonstrate the method's versatility on several model organisms, and demonstrate its utility through automated analysis of changes in fission yeast growth due to single kinase deletions. The algorithm has additionally been implemented as a stand-alone executable program to aid dissemination to other researchers.

Genomic-Morphogenetic Correlations and Evolutionary Trajectories of Bilateria

Comparative genomics helps to link characteristics of the genome and evolutionary trajectories by revealing the genomic correlates of morphological complexity and differences in the body plans of multicellular animals. Comparison of the organization of Hox clusters and expression of Hox genes with organismal morphology allows the emergence of macroevolutionary innovations as changes in morphogenesis and body plan of Bilateria, depending on the pattern of Hox code to be traced. We examine a correlation node that includes various types of organization of clustered (initially) Hox genes, early embryogenesis type, cellular developmental resources, thereby determining alternative evolutionary trajectories of various Bilateria taxa. Biological diversity inevitably manifests itself at all levels of organization and all stages of the evolution of the animal world, and therefore the reduction of the evolutionary strategies of Bilateria, and, moreover, all Metazoa, to a few simplified versions is impossible.

Ecomorphological diversity of Australian tadpoles.

Ecomorphology is the association between an organism's morphology and its ecology. Larval anuran amphibians (tadpoles) are classified into distinct ecomorphological guilds based upon morphological features and observations of their ecology. The extent to which guilds comprise distinct morphologies resulting from convergent evolution, the degree of morphological variability within each guild, and the degree of continuity in shape between guilds has not previously been examined in a phylogenetically informed statistical framework. Here, we examine tadpole ecomorphological guilds at a macroevolutionary scale by examining morphological diversity across the Australian continent. We use ecological data to classify species to guilds, and geometric morphometrics to quantify body shape in the tadpoles of 188 species, 77% of Australian frog diversity. We find that the ecomorphological guilds represented by Australian species are morphologically distinct, but there is substantial morphological variation associated with each guild, and all guilds together form a morphological continuum. However, in a phylogenetic comparative context, there is no significant difference in body shape among guilds. We also relate the morphological diversity of the Australian assemblage of tadpoles to a global sample and demonstrate that ecomorphological diversity of Australian tadpoles is limited with respect to worldwide species. Our results demonstrate that general patterns of ecomorphological variation are upheld in Australian tadpoles, but tadpole body shape is more variable and possibly generalist than generally appreciated.

Fish on steroids: Temperature-dependent effects of 17β-trenbolone on predator escape, boldness, and exploratory behaviors

Hormonal growth promoters (HGPs), widely used in beef cattle production globally, make their way into the environment as agricultural effluent—with potential impacts on aquatic ecosystems. One HPG of particular concern is 17β-trenbolone, which is persistent in freshwater habitats and can affect the development, morphology and reproductive behaviors of aquatic organisms. Despite this, few studies have investigated impacts of 17β-trenbolone on non-reproductive behaviors linked to growth and survival, like boldness and predator avoidance. None consider the interaction between 17β-trenbolone and other environmental stressors, such as temperature, although environmental challenges confronting animals in the wild seldom, if ever, occur in isolation. Accordingly, this study aimed to test the interactive effects of trenbolone and temperature on organismal behavior. To do this, eastern mosquitofish (Gambusia holbrooki) were subjected to an environmentally-relevant concentration of 17β-trenbolone (average measured concentration 3.0 ± 0.2 ng/L) or freshwater (i.e. control) for 21 days under one of two temperatures (20 and 30 °C), after which the predator escape, boldness and exploration behavior of fish were tested. Predator escape behavior was assayed by subjecting fish to a simulated predator strike, while boldness and exploration were assessed in a separate maze experiment. We found that trenbolone exposure increased boldness behavior. Interestingly, some behavioral effects of trenbolone depended on temperature, sex, or both. Specifically, significant effects of trenbolone on male predator escape behavior were only noted at 30 °C, with males becoming less reactive to the simulated threat. Further, in the maze experiment, trenbolone-exposed fish explored the maze faster than control fish, but only at 20 °C. We conclude that field detected concentrations of 17β-trenbolone can impact ecologically important behaviors of fish, and such effects can be temperature dependent. Such findings underscore the importance of considering the potentially interactive effects of other environmental stressors when investigating behavioral effects of environmental contaminants.

Under pressure: Effect of sedimentary compression on the iliac morphology of early sauropodomorphs

Sedimentary compression can produce deep changes in the organismal morphology during fossil diagenesis, so that intrinsic biological aspects (e.g. internal architecture of bones) could also generate non-natural traits when determinate bone element suffers sedimentary compression. Here we report a particular taphonomic case, in which the mode of preservation of a basal sauropodomorph from the Late Triassic of Brazil offers a valuable opportunity to examine the effects of sedimentary compression on a specific doubled body part of a single individual. The specimen is associated with two other almost complete and articulated individuals, comprising a monotypic association. The specimen herein studied presents the left ilium and hindlimb disarticulated from its body, where the right ilium was preserved with its ventral surface ventrally directed, and, conversely, the lateral surface of the left one was ventrally directed. Thus, their distinct placement in the substrate resulted in two distinct taphonomic histories reflected in their dissimilar shapes. This corresponds to a particular case of taphomorphic differences expressed in a single individual. Indeed, some of the peculiar traits of each ilium also occur in other specimens of close related taxa that experienced similar taphonomic histories. Sedimentary compression may produce dissimilar shapes in different portions of the skeleton, and incorrect observations generate what we call “taphoanatomical features”, traits shared among close phylogenetic taxa/specimens resulting from similar taphonomic processes in response to specific biological aspects of the skeleton, not necessarily expressing phylogeny. Failing to recognize these trends could affect anatomical interpretations, especially regarding their role in a phylogenetic context.

The trait-based approach as a tool to study the bio-geo seafloor system

One of the major causes of heterogeneity on the seabed is the biology. The presence of organisms creates voids and frameworks within and on the sediment, and their behavior may layer or sort the entire seafloor. Making use of the biological information would be powerful for improving acoustics. Likewise, embracing, to a greater degree, acoustic techniques and measurements to understand the biology would be favorable. However, to tackle this bio-geo diversity in a cross-disciplinary way requires a common language and approach. Here I present and propose the trait-based approach as a way forward. Because there are simply too many species to describe and include in one model, reducing this complexity is essential and can be done by considering individuals characterized by a few key characteristics, or traits. Relevant biological traits span morphology, behavior and life-history of organisms and can be applied on single individuals and scaled up to whole communities, incorporating the density of organisms. By exemplifying the progress in benthic ecology, I outline where we currently stand, possible key traits of value for both fields and ideas on how to progress.

X-ray computed tomography and its potential in ecological research: A review of studies and optimization of specimen preparation.

Imaging techniques are a cornerstone of contemporary biology. Over the last decades, advances in microscale imaging techniques have allowed fascinating new insights into cell and tissue morphology and internal anatomy of organisms across kingdoms. However, most studies so far provided snapshots of given reference taxa, describing organs and tissues under “idealized” conditions. Surprisingly, there is an almost complete lack of studies investigating how an organism′s internal morphology changes in response to environmental drivers. Consequently, ecology as a scientific discipline has so far almost neglected the possibilities arising from modern microscale imaging techniques. Here, we provide an overview of recent developments of X‐ray computed tomography as an affordable, simple method of high spatial resolution, allowing insights into three‐dimensional anatomy both in vivo and ex vivo. We review ecological studies using this technique to investigate the three‐dimensional internal structure of organisms. In addition, we provide practical comparisons between different preparation techniques for maximum contrast and tissue differentiation. In particular, we consider the novel modality of phase contrast by self‐interference of the X‐ray wave behind an object (i.e., phase contrast by free space propagation). Using the cricket Acheta domesticus (L.) as model organism, we found that the combination of FAE fixative and iodine staining provided the best results across different tissues. The drying technique also affected contrast and prevented artifacts in specific cases. Overall, we found that for the interests of ecological studies, X‐ray computed tomography is useful when the tissue or structure of interest has sufficient contrast that allows for an automatic or semiautomatic segmentation. In particular, we show that reconstruction schemes which exploit phase contrast can yield enhanced image quality. Combined with suitable specimen preparation and automated analysis, X‐ray CT can therefore become a promising quantitative 3D imaging technique to study organisms′ responses to environmental drivers, in both ecology and evolution.

Fluid flows shaping organism morphology.

A dynamic self-organized morphology is the hallmark of network-shaped organisms like slime moulds and fungi. Organisms continuously reorganize their flexible, undifferentiated body plans to forage for food. Among these organisms the slime mould Physarum polycephalumhas emerged as a model to investigate how an organism can self-organize their extensive networks and act as a coordinated whole. Cytoplasmic fluid flows flowing through the tubular networks have been identified as the key driver of morphological dynamics. Inquiring how fluid flows can shape living matter from small to large scales opens up many new avenues for research. This article is part of the theme issue 'Self-organization in cell biology'.

Contagious keratoconjuctivitis in goats due to Branhamella (Moraxella) ovis

Incidents of contagious kerato conjuctivitis in two flocks of goats in Chalkidiki Prefecture are described. The disease was only observed in young animals approximately two years of age. The early signs were excessive lacrimation, photophobia and blepharospasm, while the bright sunlight was revealed irritating for the affected eyes. Conjunctivitis and mucopurulent secretion was also observed at the late stage of the disease. Many animals with keratitis end up totally blind. The infection of the eyes was either lateral of bilateral. Branhamella ovis was isolated in almost pure culture, from lacrimal secretion in a large number of samples (32/35). The identification was based on the organism's morphology, cultural behaviour and biochemical reactions. The microbiological examination of the samples revealed only one kind of isolate. No other organisms that could cause similar clinical findings were isolated. Therefore, it was assumed that the etiological agent of the described cases was B.ovis. It is possible that certain environmental agents such as dust, flies or bright sunlight, that were present at that time of the year because of the prolonged summer, acted as predisposing factors. Although the disease exists in our country for years, it is the first time that the pathogen agent has been isolated and identified. A successful treatment was performed at the early stage of the disease by the topical application of antibiotics.

Гидрохимические характеристики и видовой состав планктона в озере Майбалык вблизи города Астана, Республика Казахстан

The study describes the result of hydrochemical and bioindicational analysis of the lake Maybalyk. The investigations revealed the main patterns which regulate the influence of hydrochemical characteristics and intensity of anthropogenic impact on the species diversity, abundance, and formation of the structure of plankton organisms. The samples for hydrochemical analysis were taken at the side of housing development on the lake Maybalyk west side and at the center of the lake. The sampling for hydrobiological analysis was carried out with the use of watercraft and cone-shaped nets. The Pantle-Buck saprobity index was used for qualitative estimation of plankton, thus the hydrobiological characteristics of the lake were estimated. The L-micro program was used for photographing in order to determine the plankton species. For aquatic organisms their external and internal environments are the same, they get oxygen and biogenic elements from their environment. Therefore their count is directly proportional to the environment composition. The main influence patterns of hydrochemical characteristics of the lake water upon the abundance and morphology of aquatic organisms have been validated. In the process of hydrochemical analysis it has been shown that concentration of chlorides, sulfates and oil products exceeds the norm for fishery waters. The possible causes for exceeding concentration and ingress of heavy metals into the lake have been determined. A possibility to use the established patterns has been shown for bioindication of natural water quality and ecological state of a water body.

Molecular mechanisms underlying stress response and adaptation.

Environmental stresses are ubiquitous and unavoidable to all living things. Organisms respond and adapt to stresses through defined regulatory mechanisms that drive changes in gene expression, organismal morphology, or physiology. Immune responses illustrate adaptation to bacterial and viral biotic stresses in animals. Dysregulation of the genotoxic stress response system is frequently associated with various types of human cancer. With respect to plants, especially halophytes, complicated systems have been developed to allow for plant growth in high salt environments. In addition, drought, waterlogging, and low temperatures represent other common plant stresses. In this review, we summarize representative examples of organismal response and adaptation to various stresses. We also discuss the molecular mechanisms underlying the above phenomena with a focus on the improvement of organismal tolerance to unfavorable environments.

Practical Guidance for Clinical Microbiology Laboratories: Laboratory Diagnosis of Parasites from the Gastrointestinal Tract

This Practical Guidance for Clinical Microbiology document on the laboratory diagnosis of parasites from the gastrointestinal tract provides practical information for the recovery and identification of relevant human parasites. The document is based on a comprehensive literature review and expert consensus on relevant diagnostic methods. However, it does not include didactic information on human parasite life cycles, organism morphology, clinical disease, pathogenesis, treatment, or epidemiology and prevention. As greater emphasis is placed on neglected tropical diseases, it becomes highly probable that patients with gastrointestinal parasitic infections will become more widely recognized in areas where parasites are endemic and not endemic. Generally, these methods are nonautomated and require extensive bench experience for accurate performance and interpretation.

The Fate of the Method of \u2018Paradigms\u2019 in Paleobiology

An earlier article described the mid-twentieth century origins of the method of “paradigms” in paleobiology, as a way of making testable hypotheses about the functional morphology of extinct organisms. The present article describes the use of “paradigms” through the 1970s and, briefly, to the end of the century. After I had proposed the paradigm method to help interpret the ecological history of brachiopods, my students developed it in relation to that and other invertebrate phyla, notably in Euan Clarkson’s analysis of vision in trilobites. David Raup’s computer-aided “theoretical morphology” was then combined with my functional or adaptive emphasis, in Adolf Seilacher’s tripartite “constructional morphology.” Stephen Jay Gould, who had strongly endorsed the method, later switched to criticizing the “adaptationist program” he claimed it embodied. Although the explicit use of paradigms in paleobiology had declined by the end of the century, the method was tacitly subsumed into functional morphology as “biomechanics.”

The trait-based approach as a powerful tool to study the bio-geo seafloor system

One of the major causes of heterogeneity on the seabed is the biology. The presence of organisms creates voids and frameworks within and on the sediment, and their behavior may layer or sort the entire seafloor. Making use of the biological information would be powerful for improving acoustics. Likewise, embracing, to a greater degree, acoustic techniques and measurements to understand the biology would be favorable. However, to tackle this bio-geo diversity in a cross-disciplinary way requires a common language and approach. Here, I present and propose the trait-based approach as a way forward. Because there are simply too many species to describe and include in one model, reducing this complexity is essential and can be done by considering individuals characterized by a few key characteristics, or traits. Relevant biological traits span morphology, behavior and life-history of organisms and can be applied on single individuals and scaled up to whole communities, incorporating the density of organisms. By exemplifying the progress in benthic ecology, I outline where we currently stand, possible key traits of value for both fields and ideas on how to progress.

Toxicity mechanisms of ionic liquids.

Over the past three decades a growing awareness of environmental protection prompted the development of so-called green and sustainable technologies. Therefore, academic and wider community intensively explores new chemicals and safer, more energy efficient processes based on a rational compromise between economic, social, and environmental requirements. Due to low volatility and stability, ionic liquids emerged as a potential replacement for traditional volatile and harmful organic solvents. Various studies have been carried out to validate the green character of ionic liquids, whereby data published suggest that these compounds, due to their relatively high toxicity and poor biodegradability, could have an extremely negative impact on the environment. This paper presents the current knowledge on the toxicity of ionic liquids, with a special emphasis on the mechanisms by which this group of compounds causes changes in the morphology and physiology of organisms at different organisational levels of the ecosystem.