scholarly journals Fin Shape, Asymmetry, and Evolutionary Ecomorphology in Triggerfishes and Filefishes (Superfamily: Balistoidea)

2021 ◽  
Author(s):  
Andrew Bradley George ◽  
Mark W. Westneat
Keyword(s):  
Swimming Performance ◽  
Morphological Diversity ◽  
Feeding Guilds ◽  
Feeding Mode ◽  
Evolutionary Patterns ◽  
Marine Habitats ◽  
Wide Range ◽  
Body Shapes ◽  
Primary Habitat ◽  
Median Fins

Triggerfishes and filefishes exhibit a wide range of fin and body morphologies, inhabit many marine habitats, and feed on a variety of benthic and pelagic organisms. Particular morphologies are predicted to provide functional advantages for swimming behaviors that facilitate life in diverse habitats and feeding guilds. Ecomorphological relationships can, in turn, inform evolutionary patterns of morphological convergence. We quantified morphological diversity of 80 balistoid species using geometric morphometrics and assigned each species a primary habitat and feeding mode. Results revealed strong evidence for evolutionary integration among body and fin shapes as well as widespread convergence of both high and low aspect ratio (AR) dorsal and anal fins, the fins that power steady locomotion in these fishes. Dorsal and anal fins were determined to be moderately to highly asymmetrical in most species. Families exhibited considerable overlap in fin and body shapes, but triggerfishes generally exhibited higher AR and more asymmetrical fins than filefishes. Fin asymmetry was not strongly associated with ecology. Planktivorous and offshore-pelagic species exhibited high AR dorsal and anal fins suitable for high endurance swimming performance, while benthic grazing and structured reef species exhibited convergence on low AR median fins more suitable for facilitating maneuverability.

scholarly journals Functional Morphology of Endurance Swimming Performance and Gait Transition Strategies in Balistoid Fishes

2018 ◽  
Author(s):  
Andrew B. George ◽  
Mark W. Westneat
Keyword(s):  
Aspect Ratio ◽  
High Speed ◽  
Swimming Performance ◽  
Gait Transition ◽  
Caudal Fin ◽  
Large Power ◽  
High Speeds ◽  
Transition Strategies ◽  
Body Shapes ◽  
Median Fins

AbstractTriggerfishes and filefishes (Balistoidea) use balistiform locomotion to power slow steady swimming with their dorsal and anal fins and transition to a gait dominated by body and caudal fin (BCF) kinematics at high speeds. Fin and body shapes are predicted to be strong determinants of swimming performance and the biomechanics of gait transitions. The goal of this study was to combine morphometrics and critical swimming tests to explore relationships between balistoid fin and body shapes and swimming performance in a phylogenetic context in order to understand the evolution and diversification of the balistiform swimming mode. Among the 13 species of balistoid fishes examined, fishes with high aspect ratio fins tended to achieve higher critical swimming speeds than fishes with low aspect ratio fins. Species with long, large median fins and wide caudal peduncles tended to use the balistiform gait alone for a larger percentage of their total critical swimming speed than fishes with short, small median fins and narrow caudal peduncles. Fishes on both ends of the aspect ratio spectrum achieved higher swimming speeds using the balistiform gait alone than fishes with median fins of intermediate aspect ratios. Each species is specialized for taking advantage of one gait, with balistiform specialists possessing long, large median fins capable of the large power requirements of swimming at high speeds using the median fins alone, while BCF specialists possess short, small median fins, ill-suited for powering high-speed balistiform locomotion, but narrow caudal peduncles capable of efficient caudal fin oscillations to power high-speed locomotion.Summary Statement:Geometric morphometrics reveal that fin and body shapes are good predictors of endurance swimming performance and gait transition strategies of triggerfishes and filefishes.

Geographic Variation in Behavior

1999 ◽  
Keyword(s):  
Geographic Variation ◽  
Animal Behavior ◽  
Evolutionary Biology ◽  
Behavioral Characteristics ◽  
Behavioral Differences ◽  
Methodological Issues ◽  
Behavioral Evolution ◽  
Evolutionary Patterns ◽  
Wide Range

Studies of animal behavior often assume that all members of a species exhibit the same behavior. Geographic Variation in Behavior shows that, on the contrary, there is substantional variation within species across a wide range of taxa. Including work from pioneers in the field, this volume provides a balanced overview of research on behavioral characteristics that vary geographically. The authors explore the mechanisms by which behavioral differences evolve and examine related methodological issues. Taken together, the work collected here demonstrates that genetically based geographic variation may be far more widespread than previously suspected. The book also shows how variation in behavior can illuminate both behavioral evolution and general evolutionary patterns. Unique among books on behavior in its emphasis on geographic variation, this volume is a valuable new resource for students and researchers in animal behavior and evolutionary biology.

scholarly journals Hydromechanics of low-Reynolds-number flow. Part 2. Singularity method for Stokes flows

1975 ◽  
Vol 67 (4) ◽  
pp. 787-815 ◽  
Author(s):  
Allen T. Chwang ◽  
T. Yao-Tsu Wu
Keyword(s):  
Exact Solutions ◽  
Stokes Flow ◽  
Fundamental Solutions ◽  
The Body ◽  
Circular Cylinders ◽  
Geometrical Parameters ◽  
Flow Problems ◽  
Singularity Method ◽  
Wide Range ◽  
Body Shapes

The present study further explores the fundamental singular solutions for Stokes flow that can be useful for constructing solutions over a wide range of free-stream profiles and body shapes. The primary singularity is the Stokeslet, which is associated with a singular point force embedded in a Stokes flow. From its derivatives other fundamental singularities can be obtained, including rotlets, stresslets, potential doublets and higher-order poles derived from them. For treating interior Stokes-flow problems new fundamental solutions are introduced; they include the Stokeson and its derivatives, called the roton and stresson.These fundamental singularities are employed here to construct exact solutions to a number of exterior and interior Stokes-flow problems for several specific body shapes translating and rotating in a viscous fluid which may itself be providing a primary flow. The different primary flows considered here include the uniform stream, shear flows, parabolic profiles and extensional flows (hyper-bolic profiles), while the body shapes cover prolate spheroids, spheres and circular cylinders. The salient features of these exact solutions (all obtained in closed form) regarding the types of singularities required for the construction of a solution in each specific case, their distribution densities and the range of validity of the solution, which may depend on the characteristic Reynolds numbers and governing geometrical parameters, are discussed.

scholarly journals ON DIVERSITY OF CONFIGURATIONS GENERATED BY EXCITABLE CELLULAR AUTOMATA WITH DYNAMICAL EXCITATION INTERVALS

2012 ◽  
Vol 23 (12) ◽  
pp. 1250085 ◽  
Author(s):  
ANDREW ADAMATZKY
Keyword(s):  
Cellular Automata ◽  
Lower Boundary ◽  
Morphological Diversity ◽  
Excitable Media ◽  
Stationary Waves ◽  
Future Studies ◽  
Time Dynamics ◽  
Wide Range ◽  
Localized Excitations ◽  
Upper Boundary

Excitable cellular automata with dynamical excitation interval exhibit a wide range of space-time dynamics based on an interplay between propagating excitation patterns which modify excitability of the automaton cells. Such interactions leads to formation of standing domains of excitation, stationary waves and localized excitations. We analyzed morphological and generative diversities of the functions studied and characterized the functions with highest values of the diversities. Amongst other intriguing discoveries we found that upper boundary of excitation interval more significantly affects morphological diversity of configurations generated than lower boundary of the interval does and there is no match between functions which produce configurations of excitation with highest morphological diversity and configurations of interval boundaries with highest morphological diversity. Potential directions of future studies of excitable media with dynamically changing excitability may focus on relations of the automaton model with living excitable media, e.g. neural tissue and muscles, novel materials with memristive properties and networks of conductive polymers.

Interactive effects of salinity on metabolic rate, activity, growth and osmoregulation in the euryhaline milkfish (Chanos chanos)

1998 ◽  
Vol 201 (24) ◽  
pp. 3355-3366
Author(s):  
C Swanson
Keyword(s):  
Metabolic Rate ◽  
High Salinity ◽  
Swimming Performance ◽  
Interactive Effects ◽  
Routine Activity ◽  
Swimming Velocity ◽  
Activity Levels ◽  
Salinity Adaptation ◽  
Chanos Chanos ◽  
Wide Range

The euryhaline milkfish (Chanos chanos) is an excellent subject for studies of the physiological and behavioral processes involved in salinity adaptation. In this study, energy partitioning for metabolism, activity and growth, maximal activity performance and blood osmotic concentrations were assessed at two activity levels in juvenile milkfish fed equal rations and maintained at a relatively constant temperature (262 C) and at salinities(15, 35 and 55 ?) that represented a wide range of osmoregulatory challenges. Changes in the measured parameters were not consistently related to the magnitude of the trans-integumentary osmotic gradients. Routine oxygen consumption rates were high in 35 ? salinity (mean 1 s.e.m. 1678 mg O2 kg-1 h-1) and comparably low in 15 and 55 ? salinity (1336 and 1273 mg O2 kg-1 h-1, respectively). Routine activity levels (relative swimming velocity) were highest in 35 ? salinity (0. 960.04 L s-1), where L is standard length, intermediate in 15 ? salinity (0.770.03 L s-1) and lowest in 55 ? salinity (0.670.03 L s-1). Growth was significantly higher in 55 ? salinity (3.40.2 % increase in wet body mass per day) than in 35 ?salinity (2.40.2 % increase per day) and intermediate in 15 ? salinity(2.90.5 % increase per day). Maximum swimming velocities decreased with increases in salinity, from 9.90.7 L s-1 in 15 ? salinity to 6.60. 5 L s-1 in 55 ? salinity. Sustained swimming activity above routine levels for 2 h resulted in an increase in blood osmotic concentrations in milkfish in 55 ?salinity, but osmoregulation was re-established during the second 2 h of activity. Thus, patterns of variation in metabolic rate and growth were largely parallel to variations in routine activity although, comparing 15 and 55 ? salinity, elevated maintenance costs for osmoregulation at the high salinity were detectable. Reduced osmoregulatory abilities and reductions in maximal swimming performance suggest that high salinity may constrain activity. The results demonstrate that investigations of salinity adaptation in euryhaline fishes should take into account the interactive effects of salinity on physiology and behavior.

scholarly journals HIV-1 Evolutionary Patterns Associated with Metastatic Kaposi’s Sarcoma during AIDS

Sarcoma ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Susanna L. Lamers ◽  
Rebecca Rose ◽  
David J. Nolan ◽  
Gary B. Fogel ◽  
Andrew E. Barbier ◽  
...  
Keyword(s):  
Kaposi's Sarcoma ◽  
Kaposi’S Sarcoma ◽  
Inflammatory Cells ◽  
Selective Advantage ◽  
Evolutionary Patterns ◽  
Single Genome ◽  
Wide Range ◽  
Life Threatening ◽  
Infected Cells ◽  
Autopsy Tissues

Kaposi’s sarcoma (KS) in HIV-infected individuals can have a wide range of clinical outcomes, from indolent skin tumors to a life-threatening visceral cancer. KS tumors contain endothelial-related cells and inflammatory cells that may be HIV-infected. In this study we tested if HIV evolutionary patterns distinguish KS tumor relatedness and progression. Multisite autopsies from participants who died from HIV-AIDS with KS prior to the availability of antiretroviral therapy were identified at the AIDS and Cancer Specimen Resource (ACSR). Two patients (KS1 and KS2) died predominantly from non-KS-associated disease and KS3 died due to aggressive and metastatic KS within one month of diagnosis. Skin and visceral tumor and nontumor autopsy tissues were obtained (n=12). Single genome sequencing was used to amplify HIV RNA and DNA, which was present in all tumors. Independent HIV tumor clades in phylogenies differentiated KS1 and KS2 from KS3, whose sequences were interrelated by both phylogeny and selection. HIV compartmentalization was confirmed in KS1 and KS2 tumors; however, in KS3, no compartmentalization was observed among sampled tissues. While the sample size is small, the HIV evolutionary patterns observed in all patients suggest an interplay between tumor cells and HIV-infected cells which provides a selective advantage and could promote KS progression.

NUMERICAL ANALYSES OF LEAF AND FRUIT EXTERNAL MORPHOLOGY IN Moringa oleifera LAM

2015 ◽  
Vol 77 (13) ◽  
Author(s):  
Daniel Andrawus Zhigila ◽  
Sulaiman Mohammed ◽  
Felix Ayodele Oladele ◽  
Fatima B. J. Sawa
Keyword(s):  
Moringa Oleifera ◽  
Crop Improvement ◽  
Morphological Diversity ◽  
External Morphology ◽  
Numerical Analyses ◽  
Qualitative And Quantitative ◽  
Quantitative Characters ◽  
Diversity Assessment ◽  
Wide Range ◽  
Improvement Programme

The wide range of uses of Moringa oleifera in recent time has witnessed increasing demand of its foliar and seed products in nutritional, medical and ecological applications. The upsurge of demand for these products needs to be balanced with new varieties of improved performance to meet the supply chain. To achieve this, morphological diversity assessment is prerequisite for future crop improvement programme. Therefore, numerical analyses of the external morphology of leaf and fruit of thirty accessions of Moringa oleifera were assessed. The study was carried out on both qualitative and quantitative characters to assess the diversity at morphological level to establish the phenetic relationships and the delimitation of accessions. Relationship studies showed considerable correlation between the leaf and fruits characters that produced clear and reproducible threats and were selected for diversity study. Numerical analysis of the qualitative and quantitative characters clustered the accessions into five groups – operational taxonomic units (OTUs) 1, 2, 3, 4, 5, 7, 9, 10, 11, 12, 13, 14, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30 were clustered in group one; OTUs 6 and 8 were clustered in group two and three respectively; OTUs 15 and 16 in group four and OUT 23 in group five cluster membership. Principal Component Analysis was carried out to augment the Cluster Analysis which showed large morphological diversity existing in accessions of Moringa oleifera hence, infraspecific classification is hereby proposed.  These analysis particularly traits related to leaf and fruits yield can also be utilised for crop improvement programme.

scholarly journals Protecting the North Sea: New research for biodiversity recovery.

2020 ◽  
Author(s):  
Oceana ◽  
Helena Álvarez ◽  
Allison L. Perry ◽  
Jorge Blanco ◽  
Silvia Garcia ◽  
...  
Keyword(s):  
North Sea ◽  
Marine Biodiversity ◽  
Legal Requirements ◽  
Marine Life ◽  
The North ◽  
Marine Habitats ◽  
Wide Range ◽  
The Face ◽  
The North Sea ◽  
New Research

To help fill gaps in knowledge about marine biodiversity in the North Sea, Oceana carried out two eight week research expeditions, in 2016 and 2017. Oceana’s surveys documented a wide range of habitats and species that are considered priorities for conservation, under national, EU, and international frameworks that recognise them as threatened and/or establish legal requirements for their protection.Oceana’s research has underscored the fact that much remains to be discovered about marine life on the seabed of the North Sea. Continued research is critical for informing efforts to recover biodiversity, an urgent priority in the face of the multiple, intense pressures facing the North Sea’s marine habitats and species.

scholarly journals New handbook for standardised measurement of plant functional traits worldwide

2013 ◽  
Vol 61 (3) ◽  
pp. 167 ◽  
Author(s):  
N. Pérez-Harguindeguy ◽  
S. Díaz ◽  
E. Garnier ◽  
S. Lavorel ◽  
H. Poorter ◽  
...  
Keyword(s):  
Functional Traits ◽  
Environmental Changes ◽  
Plant Traits ◽  
Leaf Traits ◽  
Plant Functional Traits ◽  
Trophic Levels ◽  
Evolutionary Patterns ◽  
Ecosystem Properties ◽  
Species Invasions ◽  
Wide Range

Plant functional traits are the features (morphological, physiological, phenological) that represent ecological strategies and determine how plants respond to environmental factors, affect other trophic levels and influence ecosystem properties. Variation in plant functional traits, and trait syndromes, has proven useful for tackling many important ecological questions at a range of scales, giving rise to a demand for standardised ways to measure ecologically meaningful plant traits. This line of research has been among the most fruitful avenues for understanding ecological and evolutionary patterns and processes. It also has the potential both to build a predictive set of local, regional and global relationships between plants and environment and to quantify a wide range of natural and human-driven processes, including changes in biodiversity, the impacts of species invasions, alterations in biogeochemical processes and vegetation–atmosphere interactions. The importance of these topics dictates the urgent need for more and better data, and increases the value of standardised protocols for quantifying trait variation of different species, in particular for traits with power to predict plant- and ecosystem-level processes, and for traits that can be measured relatively easily. Updated and expanded from the widely used previous version, this handbook retains the focus on clearly presented, widely applicable, step-by-step recipes, with a minimum of text on theory, and not only includes updated methods for the traits previously covered, but also introduces many new protocols for further traits. This new handbook has a better balance between whole-plant traits, leaf traits, root and stem traits and regenerative traits, and puts particular emphasis on traits important for predicting species’ effects on key ecosystem properties. We hope this new handbook becomes a standard companion in local and global efforts to learn about the responses and impacts of different plant species with respect to environmental changes in the present, past and future.

The bacteria of the sulphur cycle

1982 ◽  
Vol 298 (1093) ◽  
pp. 433-441 ◽  
Keyword(s):  
Organic Matter ◽  
Degradation Products ◽  
Morphological Diversity ◽  
Elemental Sulphur ◽  
Sulphur Compounds ◽  
Sulphate Reducing Bacteria ◽  
Marine Habitats ◽  
Sulphur Bacteria ◽  
Terminal Oxidation ◽  
Reducing Bacteria

This paper concentrates on the bacteria involved in the reductions and oxidations of inorganic sulphur compounds under anaerobic conditions. The genera of the dissimilatory sulphate-reducing bacteria known today are discussed with respect to their different capacities to decompose and oxidize various products of fermentative degradations of organic matter. The utilization of molecular hydrogen and formate by sulphate reducers shifts fermentations towards the energetically more favourable formation of acetate. Since acetate amounts to about two-thirds of the degradation products of organic matter, the complete anaerobic oxidation of acetate by several genera of the sulphate-reducing bacteria is an important function for terminal oxidation in sulphatesufficient environments. The results of pure culture studies agree well with ecological investigations of several authors who showed the significance of sulphate reduction for the complete oxidation of organic matter in anaerobic marine habitats. In the dissimilatory sulphur-reducing bacteria of the genus Desulfuromonas the oxidation of acetate is linked to the reduction of elemental sulphur. Major characteristics of the anaerobic, sulphide-oxidizing phototrophic green and purple sulphur bacteria as well as of some facultative anoxygenic cyanobacteria are given. By the formation of elemental sulphur and sulphate, these bacteria establish sulphur cycles with the sulphide-forming bacteria. In view of the morphological diversity of the sulphate-reducing bacteria the question of possible evolutionary relations to phototrophic sulphur bacteria is raised.

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