scholarly journals Shared ecological traits influence shape of the skeleton in flatfishes (Pleuronectiformes)

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8919
Author(s):  
Corinthia R. Black ◽  
Peter B. Berendzen
Keyword(s):  
Body Shape ◽  
Middle Miocene ◽  
Linear Models ◽  
Phylogenetic Signal ◽  
X Rays ◽  
Ecological Traits ◽  
Body Depth ◽  
Primary Focus ◽  
Diverse Groups ◽  
Fin Length

In the age of phylogenetic comparative methods, evolutionary biologists have been able to explore evolutionary trends in form in unique and extraordinarily diverse groups of animals. Pleuronectiformes, commonly known as flatfishes, is a diverse and specialized order of fishes that have remarkable asymmetry induced by ocular migration and a benthic life style. Although flatfishes are unique from other fishes, species within the group are morphologically diverse. The origin of ocular migration has been a primary focus of research; however, little is known about overall shape diversification among the flatfishes. In this study, we use integrative methods to examine how body shape evolved within the flatfishes. Shape was quantified from X-rays using geometric morphometrics for 389 individuals across 145 species. The most recent and robust phylogeny was overlaid onto the morphospace and phylogenetic signal was calculated to ascertain convergence in the morphospace. In addition, phylogenetic linear models were employed to determine if ecological traits were correlated with shape and if size had an effect on overall body shape. Results revealed that the majority of variation evolved recently, within the past 15–10-million-years in the middle Miocene, and is highly variable within the flatfishes. These changes are best summarized by body depth, jaw length and medial fin length. Dorsal and anal fin length are correlated, which may be due to the unique mode of locomotion used by flatfishes. A phylogenetic linear model and phylomorphospace analysis suggested that several ecological traits are correlated with shape, which indicates an ecological role in the diversification of flatfishes.

Larval morphology predicts geographical dispersal range of Eastern Pacific eels

2019 ◽  
Vol 128 (1) ◽  
pp. 107-121 ◽  
Author(s):  
Katherine E Dale ◽  
M Timothy Tinker ◽  
Rita S Mehta
Keyword(s):  
Body Shape ◽  
Phylogenetic Signal ◽  
Morphological Diversity ◽  
Marine Species ◽  
Eastern Pacific ◽  
Geographical Range ◽  
Larval Body ◽  
Adult Morphology ◽  
Adult Habitat ◽  
Eggs And Larvae

Abstract The geographical range of many marine species is strongly influenced by the dispersal potential of propagules such as eggs and larvae. Here, we investigate morphological diversity and the effect of body shape on geographical range of leptocephali, the unique, laterally compressed larvae of eels (order Anguilliformes). We used phylogenetically informed analyses to examine the morphological variation of larvae for 17 Eastern Pacific eel species from three adult habitats. We also investigated whether morphological traits of leptocephali could predict larval latitudinal range, hypothesizing that body shape may influence passive dispersal via currents. We found that no two species shared the same multivariate growth trajectories, with the size and scaling of pectoral fin length and snout-to-anus length being particularly variable. Larvae with longer relative predorsal and snout-to-anus lengths at median sizes exhibited wider larval geographical ranges. Body aspect ratio and maximum body length at metamorphosis, two traits we hypothesized to be important for passive transport, were not significant predictors of maximal larval range. We discovered an increase in phylogenetic signal over larval development as eels approach metamorphosis, potentially due to similar selective pressures between related species (such as juvenile habitat or adult morphology). Lastly, we conclude that larval body shape is probably influenced by adult habitat and adult morphology.

scholarly journals Evaluating Phylogenetic Informativeness as a Predictor of Phylogenetic Signal for Metazoan, Fungal, and Mammalian Phylogenomic Data Sets

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Francesc López-Giráldez ◽  
Andrew H. Moeller ◽  
Jeffrey P. Townsend
Keyword(s):  
Phylogenetic Signal ◽  
Simulated Data ◽  
Quantitative Measure ◽  
Data Sets ◽  
Phylogenetic Informativeness ◽  
Phylogenetic Resolution ◽  
Taxonomic Groups ◽  
Diverse Groups ◽  
Simulated Data Sets ◽  
Selection Of

Phylogenetic research is often stymied by selection of a marker that leads to poor phylogenetic resolution despite considerable cost and effort. Profiles of phylogenetic informativeness provide a quantitative measure for prioritizing gene sampling to resolve branching order in a particular epoch. To evaluate the utility of these profiles, we analyzed phylogenomic data sets from metazoans, fungi, and mammals, thus encompassing diverse time scales and taxonomic groups. We also evaluated the utility of profiles created based on simulated data sets. We found that genes selected via their informativeness dramatically outperformed haphazard sampling of markers. Furthermore, our analyses demonstrate that the original phylogenetic informativeness method can be extended to trees with more than four taxa. Thus, although the method currently predicts phylogenetic signal without specifically accounting for the misleading effects of stochastic noise, it is robust to the effects of homoplasy. The phylogenetic informativeness rankings obtained will allow other researchers to select advantageous genes for future studies within these clades, maximizing return on effort and investment. Genes identified might also yield efficient experimental designs for phylogenetic inference for many sister clades and outgroup taxa that are closely related to the diverse groups of organisms analyzed.

Precision of a Novel Vertebral Motion Analysis System: Preliminary Results

2012 ◽  
Author(s):  
Matthew S. Yeager ◽  
Daniel J. Cook ◽  
Boyle C. Cheng
Keyword(s):  
Muscle Activation ◽  
X Rays ◽  
Current Standard ◽  
Body Depth ◽  
Standard Of Practice ◽  
Static Images ◽  
Magnetic Resonance Imaging Mri ◽  
Analysis System ◽  
High Level ◽  
Relative Change

Imaging modalities such as X-Ray, computerized tomography (CT), magnetic resonance imaging (MRI), and bone scan have all become essential to the evaluation of bone and soft tissue in patients with back pain. All techniques provide valuable static images of the spine, yet lack the capability of providing detailed information about spinal motion. Dynamic end-range x-rays, the standard in assessment of range of motion and vertebral translation, are taken at the patient’s maximum voluntary bending angle in flexion and extension (FE) and/or lateral bending (LB). The current standard of practice is to measure, with ruler and protractor, the relative change between adjacent vertebrae at each bending extreme. The resulting rotational or translational values are then expressed as the intervertebral angle (IVA) or as a percentage of vertebral body depth, respectively. This method, however, is subject to a high level of patient, imaging site, and observer related variability, in the form of uncontrolled bending angles, disparities in equipment and practices, and manual image analysis. An additional limitation of static imagery is the inability to assess motion in the spine as it traverses between end ranges. This information may expose motion abnormalities that occur mid-range that might otherwise be missed by clinicians. Lastly, motion of the spine may present differently in weighted and un-weighted positions. Effects of muscle activation and gravitational forces are not accounted for by current standards.

scholarly journals Phylogenomics, Biogeography, and Morphometrics Reveal Rapid Phenotypic Evolution in Pythons After Crossing Wallace’s Line

2020 ◽  
Vol 69 (6) ◽  
pp. 1039-1051 ◽  
Author(s):  
Damien Esquerré ◽  
Stephen Donnellan ◽  
Ian G Brennan ◽  
Alan R Lemmon ◽  
Emily Moriarty Lemmon ◽  
...  
Keyword(s):  
Body Shape ◽  
Habitat Preferences ◽  
Ecological Niches ◽  
Mitochondrial Genomes ◽  
Phenotypic Evolution ◽  
Conservative Group ◽  
Anchored Hybrid Enrichment ◽  
Nuclear Loci ◽  
Wallace’S Line ◽  
Diverse Groups

Abstract Ecological opportunities can be provided to organisms that cross stringent biogeographic barriers towards environments with new ecological niches. Wallace’s and Lyddeker’s lines are arguably the most famous biogeographic barriers, separating the Asian and Australo-Papuan biotas. One of the most ecomorphologically diverse groups of reptiles, the pythons, is distributed across these lines, and are remarkably more diverse in phenotype and ecology east of Lydekker’s line in Australo-Papua. We used an anchored hybrid enrichment approach, with near complete taxon sampling, to extract mitochondrial genomes and 376 nuclear loci to resolve and date their phylogenetic history. Biogeographic reconstruction demonstrates that they originated in Asia around 38-45 Ma and then invaded Australo-Papua around 23 Ma. Australo-Papuan pythons display a sizeable expansion in morphological space, with shifts towards numerous new adaptive optima in head and body shape, coupled with the evolution of new micro-habitat preferences. We provide an updated taxonomy of pythons and our study also demonstrates how ecological opportunity following colonization of novel environments can promote morphological diversification in a formerly ecomorphologically conservative group. [Adaptive radiation; anchored hybrid enrichment; biogeography; morphometrics; snakes.]

Morphological differences among females of four species of stickleback (Gasterosteidae) from New Brunswick and their possible ecological significance

1987 ◽  
Vol 65 (2) ◽  
pp. 289-295 ◽  
Author(s):  
J. Charles Delbeek ◽  
D. Dudley Williams
Keyword(s):  
Life Histories ◽  
East Coast ◽  
Prey Size ◽  
Significant Negative Correlation ◽  
Morphological Characters ◽  
Body Depth ◽  
Morphological Differences ◽  
Gill Raker ◽  
Gut Length ◽  
Fin Length

Fifteen morphological characters were measured from females of four species of stickleback (Gasterosteidae) collected from the east coast of Canada. Significant differences were found between the species for 12 of these characters. All four species were found to differ significantly in their gill raker number. Gasterosteus had the greatest number of gill rakers followed by Pungitius and Apeltes. A significant negative correlation between gill raker number and prey size was demonstrated; Gasterosteus fed to a greater extent on smaller, planktonic prey, while Pungitius and Apeltes fed on larger, benthic prey. Gasterosteus were found also to have larger pectoral and caudal fin areas, and shorter but wider caudal peduncles, than Pungitius and Apeltes. The larger fins of Gasterosteus are probably a reflection of their increased swimming ability in response to the pelagic phase of their life histories. The longer, narrower caudal peduncles of Pungitius and Apeltes are probably an adaptation to life in weedy habitats where high manoeuverability is desired. The significance of these characters, as well as mouth height, pelvic fin length, body depth, gut length, head length, and pectoral fin length, are further discussed with respect to observed differences in diet, habitat, and life histories.

scholarly journals Towards a morphological metric of assemblage dynamics in the fossil record: a test case using planktonic foraminifera

2016 ◽  
Vol 371 (1691) ◽  
pp. 20150227 ◽  
Author(s):  
Allison Y. Hsiang ◽  
Leanne E. Elder ◽  
Pincelli M. Hull
Keyword(s):  
Fossil Record ◽  
Phylogenetic Signal ◽  
Planktonic Foraminifera ◽  
Three Dimensional ◽  
Test Case ◽  
Ecological Traits ◽  
The North ◽  
Extant Species ◽  
The Relationship ◽  
Assemblage Size

With a glance, even the novice naturalist can tell you something about the ecology of a given ecosystem. This is because the morphology of individuals reflects their evolutionary history and ecology, and imparts a distinct ‘look’ to communities—making it possible to immediately discern between deserts and forests, or coral reefs and abyssal plains. Once quantified, morphology can provide a common metric for characterizing communities across space and time and, if measured rapidly, serve as a powerful tool for quantifying biotic dynamics. Here, we present and test a new high-throughput approach for analysing community shape in the fossil record using semi-three-dimensional (3D) morphometrics from vertically stacked images (light microscopic or photogrammetric). We assess the potential informativeness of community morphology in a first analysis of the relationship between 3D morphology, ecology and phylogeny in 16 extant species of planktonic foraminifera—an abundant group in the marine fossil record—and in a preliminary comparison of four assemblages from the North Atlantic. In the species examined, phylogenetic relatedness was most closely correlated with ecology, with all three ecological traits examined (depth habitat, symbiont ecology and biogeography) showing significant phylogenetic signal. By contrast, morphological trees (based on 3D shape similarity) were relatively distantly related to both ecology and phylogeny. Although improvements are needed to realize the full utility of community morphometrics, our approach already provides robust volumetric measurements of assemblage size, a key ecological characteristic.

scholarly journals Movement pathways and habitat selection by woodland caribou during spring migration

Rangifer ◽  
2005 ◽  
Vol 25 (4) ◽  
pp. 143 ◽  
Author(s):  
D. Joanne Saher ◽  
Fiona K.A. Schmiegelow
Keyword(s):  
Habitat Selection ◽  
Land Use Planning ◽  
Resource Selection ◽  
Rangifer Tarandus ◽  
Linear Models ◽  
Woodland Caribou ◽  
Winter Habitat ◽  
System Data ◽  
Primary Focus ◽  
Migratory Movements

Woodland caribou (Rangifer tarandus caribou) are a threatened species throughout Canada. Special management is therefore required to ensure habitat needs are met, particularly because much of their current distribution is heavily influenced by resource extraction activities. Although winter habitat is thought to be limiting and is the primary focus of conservation efforts, maintaining connectivity between summer and winter ranges has received little attention. We used global positioning system data from an interprovincial, woodland caribou herd to define migratory movements on a relatively pristine range. Non-linear models indicated that caribou movement during migration was punctuated; caribou traveled for some distance (movement phase) followed by a pause (resting/foraging phase). We then developed resource selection functions (RSFs), using case-controlled logistic regression, to describe resting/foraging sites and movement sites, at the landscape scale. The RSFs indicated that caribou traveled through areas that were less rugged and closer to water than random and that resting/foraging sites were associated with older forests that have a greater component of pine, and are further from water than were random available locations. This approach to analyzing animal location data allowed us to identify two patterns of habitat selection (travel and foraging/resting) for caribou during the migratory period. Resultant models are important tools for land use planning to ensure that connectivity between caribou summer and winter ranges is maintained.

scholarly journals Host Phylogeny Matters: Examining Sources of Variation in Infection Risk by Blood Parasites Across a Tropical Montane Bird Community in India

2020 ◽  
Author(s):  
Pooja Gupta ◽  
C.K. Vishnudas ◽  
V.V. Robin ◽  
Guha Dharmarajan
Keyword(s):  
Phylogenetic Relationships ◽  
Phylogenetic Signal ◽  
Infection Risk ◽  
Bird Communities ◽  
Blood Parasites ◽  
Ecological Traits ◽  
Mixed Effect ◽  
Ecological Predictors ◽  
Mitochondrial Cytochrome B ◽  
Host Phylogeny

Abstract Background: Identifying patterns and drivers of infection risk among host communities is crucial to elucidate disease dynamics and predict infectious disease risk in wildlife populations. Blood parasites of genera Plasmodium and Haemoproteus are a diverse group of vector-borne protozoan parasites that affected bird populations globally. Despite their widespread distribution and exceptional diversity, factors underlying haemosporidian infection risk in wild bird communities remain poorly understood. While some studies have examined variation in avian haemosporidian risk, researchers have primarily focused on host ecological traits without considering host phylogenetic relationships. In this study, we employ a phylogenetically informed approach to examine the association between host ecological traits and avian haemosporidian infection risk in endemic bird communities in the Western Ghats Sky Islands.Methods: We collected blood samples from 1177 birds (28 species) and amplified partial parasite mitochondrial cytochrome b gene to identify avian haemosporidian infection and characterized unique haemosporidian lineages by sequencing. We employed a Bayesian phylogenetic mixed effect modelling approach to test the association between seven species specific ecological predictors, four individual level predictors and avian haemosporidian infection risk. We also examined the effect of host phylogenetic relationships on the observed patterns of variation in haemosporidian infection risk by estimating phylogenetic signal.Results: Our study shows that effects of host ecological traits and host phylogeny on infection risk vary for Plasmodium (generalist parasite) vs. Haemoproteus (specialist parasite). For Plasmodium, we found that sociality, sexual dimorphism and feeding strata were important ecological predictors. For Haemoproteus, patterns of infection risk among host species were associated with sociality, elevation and individual body condition. Interestingly, variance in infection risk explained by host phylogeny was higher for Haemoproteus parasites compared to Plasmodium. Conclusion: Our study highlights that while host ecological traits promoting parasite exposure and host susceptibility are important determinants of infection risk, host phylogeny also contributes substantially in predicting patterns of avian haemosporidian infection risk among host communities. Importantly, infection risk is driven by joint contributions of host ecology and host phylogeny and studying these effects together could increase our ability to better understand the drivers of infection risk and predict future disease threats.

Clarias gracilentus, a new walking catfish (Teleostei: Clariidae) from Vietnam and Cambodia

Zootaxa ◽  
2011 ◽  
Vol 2823 (1) ◽  
pp. 61 ◽  
Author(s):  
HEOK HEE NG ◽  
DANG KHANH HONG ◽  
NGUYEN VAN TU
Keyword(s):  
Species Complex ◽  
Head Width ◽  
Body Depth ◽  
Dorsal Fin ◽  
Fin Ray ◽  
Fin Rays ◽  
Eye Diameter ◽  
Process Length ◽  
Fin Length ◽  
Pelvic Fin

Clarias gracilentus, a new Southeast Asian walking catfish species, is described from Phu Quoc Island (Vietnam) off the coast of southeastern Cambodia and from mainland southeastern Cambodia. The new species is a member of the C. nieuhofii species complex, and can be distinguished from congeners in the complex in having a combination of: head width 11.9–12.9% SL, distance between the occipital process and the base of the first dorsal-fin ray 5.3–8.4% SL, pectoral-fin length 8.5–10.1% SL, body depth at anus 8.2–11.7% SL, pelvic-fin length 4.3–5.5% SL, length of anal-fin base 60.0–63.9% SL, eye diameter 5.4–7.2% HL, interorbital distance 42.7–48.0% HL, occipital-process length 7.8–14.7% HL, 96–101 dorsal-fin rays, 84–89 anal-fin rays and 80–84 total vertebrae.

scholarly journals A New Record of the Pseudolaguvia nubila (Siluriformes: Erethistidae) from Baandhkhola (Stream) in Central Nepal

2017 ◽  
Vol 5 (4) ◽  
pp. 434-441
Author(s):  
Asha Rayamajhi ◽  
M. Arunachalam
Keyword(s):  
New Record ◽  
Outer Edge ◽  
Pectoral Fin ◽  
Body Depth ◽  
Spine Length ◽  
Dorsal Fin ◽  
Central Nepal ◽  
The Family ◽  
Fin Length

In this study, we describe a miniature sisorid catfish of the family Erethistidae, as a new distributional record of Pseudolaguvia nubila from the Baandhkhola (stream), a tributary of Narayani River inCentral Nepal. Pseudolaguvia nubila shows its distribution to Nepal is distinguished from its congeners by combination of characters, such as- two broad and distinct yellowish vertical bands at the origin of dorsal fin and anal fin, smooth outer edge of the dorsal fin spine, dorsal fin spine length 13.23-17.60 % SL, pectoral fin length 24.89-26.27 % SL, pectoral fin spine length 18.39-19.48 % SL and body depth at anus 17.22-18.69 % SL.Int. J. Appl. Sci. Biotechnol. Vol 5(4): 434-441

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