scholarly journals Exquisitely Preserved Fossil Snakes of Messel: Insight into the Evolution, Biogeography, Habitat Preferences and Sensory Ecology of Early Boas

Diversity ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 100 ◽  
Author(s):  
Agustín Scanferla ◽  
Krister T. Smith
Keyword(s):  
Body Size ◽  
New World ◽  
Middle Eocene ◽  
Habitat Preferences ◽  
Sensory Ecology ◽  
Morphological Diversity ◽  
Predator Prey ◽  
Upper Jaw ◽  
Spectrum Evaluation ◽  
Insight Into

Our knowledge of early evolution of snakes is improving, but all that we can infer about the evolution of modern clades of snakes such as boas (Booidea) is still based on isolated bones. Here, we resolve the phylogenetic relationships of Eoconstrictor fischeri comb. nov. and other booids from the early-middle Eocene of Messel (Germany), the best-known fossil snake assemblage yet discovered. Our combined analyses demonstrate an affinity of Eoconstrictor with Neotropical boas, thus entailing a South America-to-Europe dispersal event. Other booid species from Messel are related to different New World clades, reinforcing the cosmopolitan nature of the Messel booid fauna. Our analyses indicate that Eoconstrictor was a terrestrial, medium- to large-bodied snake that bore labial pit organs in the upper jaw, the earliest evidence that the visual system in snakes incorporated the infrared spectrum. Evaluation of the known palaeobiology of Eoconstrictor provides no evidence that pit organs played a role in the predator–prey relations of this stem boid. At the same time, the morphological diversity of Messel booids reflects the occupation of several terrestrial macrohabitats, and even in the earliest booid community the relation between pit organs and body size is similar to that seen in booids today.

You Are Where You Live: Using the size of conodont dental tools to shed light on environmental conditions and community complexity

2020 ◽  
Author(s):  
Laura Mulvey ◽  
Bryan Shirley ◽  
Fiona Pye ◽  
Nussaïbah B. Raja ◽  
Emilia Jarochowska
Keyword(s):  
Body Size ◽  
Species Turnover ◽  
Size Analysis ◽  
Clear Correlation ◽  
Size Change ◽  
Predator Prey ◽  
Wide Range ◽  
Community Complexity ◽  
The Impact ◽  
Insight Into

<p>One of the most versatile tools in a palaeontologists’ “tool-kit” is body size analysis, which can be used to characterise and quantify a wide range of ecological and physiological traits.  Utilisation of these data allows insight into predator prey relationships, respiration rates, mortality rates, and even population dynamics. Body size analysis becomes essential when studying extinct organisms where few other clues to their ecology are available. An extreme example of such organisms are conodonts, which are hypothesised to be among the first predators.  Here, changes are tracked  through the Silurian Period using coniform conodont elements as a proxy for body size. Previous research focuses primarily on species turnover, however the data collected in this study is independent of species identification, relying purely on body size changes to reflect the ecology of the community. The size of coniform elements are measured across a number of bathymetries spanning approximately 10 million years. This allows a comparison of body size change not only across differing environments, but also through time. The morphometric measurements were determined using FossilJ, a plugin for ImageJ which facilitates semi-automated measurement of two-dimensional images. Firstly, our results show a clear correlation between body size change and onshore offshore gradients with smaller organisms residing at shallower water depths, unlike what is seen in today’s oceans. Secondly, specimens span across two of the three recorded isotopic excursions during the Silurian Period, the Mulde and Lau events. The impact of these events on conodont communities is represented by a reduction in body size directly after each. Furthermore, the results suggest the Mulde event may have had a stronger effect on these communities and could potentially reflect a time of stress and/or extinction for coniform conodonts.</p>

Length-mass relationships among an assemblage of tropical snakes in Costa Rica

1990 ◽  
Vol 6 (1) ◽  
pp. 65-76 ◽  
Author(s):  
Craig Guyer ◽  
Maureen A. Donnelly
Keyword(s):  
Species Richness ◽  
Body Size ◽  
Costa Rica ◽  
Leaf Litter ◽  
Habitat Preferences ◽  
Tail Length ◽  
Morphological Diversity ◽  
Relative Mass ◽  
Mass Measurements ◽  
La Selva

ABSTRACTLength-mass relationships within an assemblage of tropical snakes are used to describe morphological groups. We report patterns of body size based on length and mass measurements of 603 individual snakes of 27 species captured at La Selva, Costa Rica from March 1982 through August 1984. This assemblage of snakes is composed of at least four morphological groups each of which consists of species with similar habitat preferences. These groups are heavy-bodied terrestrial forms, light-bodied arboreal forms, long-tailed leaf-litter forms, and forms of unextreme relative mass and tail length. This tropical snake assemblage is more diverse in species richness and morphological diversity than a temperate assemblage.

scholarly journals Functional genomics study of Pseudomonas putida to determine traits associated with avoidance of a myxobacterial predator

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shukria Akbar ◽  
D. Cole Stevens
Keyword(s):  
Pseudomonas Putida ◽  
Bacterial Communities ◽  
Predator Avoidance ◽  
Phenotypic Diversity ◽  
Myxococcus Xanthus ◽  
Predator Prey ◽  
Mucoid Conversion ◽  
Small Colony ◽  
Predator Prey Models ◽  
Insight Into

AbstractPredation contributes to the structure and diversity of microbial communities. Predatory myxobacteria are ubiquitous to a variety of microbial habitats and capably consume a broad diversity of microbial prey. Predator–prey experiments utilizing myxobacteria have provided details into predatory mechanisms and features that facilitate consumption of prey. However, prey resistance to myxobacterial predation remains underexplored, and prey resistances have been observed exclusively from predator–prey experiments that included the model myxobacterium Myxococcus xanthus. Utilizing a predator–prey pairing that instead included the myxobacterium, Cystobacter ferrugineus, with Pseudomonas putida as prey, we observed surviving phenotypes capable of eluding predation. Comparative transcriptomics between P. putida unexposed to C. ferrugineus and the survivor phenotype suggested that increased expression of efflux pumps, genes associated with mucoid conversion, and various membrane features contribute to predator avoidance. Unique features observed from the survivor phenotype when compared to the parent P. putida include small colony variation, efflux-mediated antibiotic resistance, phenazine-1-carboxylic acid production, and increased mucoid conversion. These results demonstrate the utility of myxobacterial predator–prey models and provide insight into prey resistances in response to predatory stress that might contribute to the phenotypic diversity and structure of bacterial communities.

scholarly journals Additional records and stratigraphic distribution of the middle Eocene carettochelyid turtle Anosteira pulchra from the Uinta Formation of Utah, North America

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9775
Author(s):  
Brent Adrian ◽  
Patricia A. Holroyd ◽  
J. Howard Hutchison ◽  
KE Beth Townsend
Keyword(s):  
North America ◽  
New Records ◽  
Middle Eocene ◽  
Single Species ◽  
Uinta Basin ◽  
Stratigraphic Framework ◽  
Multiple Levels ◽  
Land Mammal ◽  
Anatomical Information ◽  
Insight Into

Background Anosteira pulchra is one of two species of the obligately-aquatic freshwater clade Carettochelyidae (pig-nosed turtles) from the Eocene of North America. Anosteira pulchra is typically rare in collections, and their distribution is poorly documented. The Uinta Formation [Fm.] contains a diverse assemblage of turtles from the Uintan North American Land Mammal Age. Whereas turtles are abundantly preserved in the Uinta Fm., A. pulchra has been reported only from a few specimens in the Uinta C Member. Methods We describe new records of Anosteira pulchra from the Uinta Basin and analyze the distribution of 95 specimens from multiple repositories in the previously published stratigraphic framework of the middle and upper Uinta Fm. Results Here we report the first records of the species from the Uinta B interval, document it from multiple levels within the stratigraphic section and examine its uncommon appearance in only approximately 5% of localities where turtles have been systematically collected. This study details and extends the range of A. pulchra in the Uinta Fm. and demonstrates the presence of the taxon in significantly lower stratigraphic layers. These newly described fossils include previously unknown elements and associated trace fossils, with new anatomical information presented. This study provides insight into the taxonomy of Anosteira spp. in the middle Eocene, and suggests the presence of a single species, though no synonymy is defined here due to limits in Bridger material.

scholarly journals Caenagnathids of the Dinosaur Park Formation (Campanian) of Alberta, Canada: anatomy, osteohistology, taxonomy, and evolution

2020 ◽  
Vol 8 ◽  
pp. 105-153 ◽  
Author(s):  
Gregory Funston
Keyword(s):  
Body Size ◽  
Skeletal Maturity ◽  
Niche Overlap ◽  
Niche Space ◽  
The Past ◽  
Adult Body ◽  
New Material ◽  
Taxonomic Framework ◽  
Dinosaur Park Formation ◽  
Insight Into

Our understanding of caenagnathid anatomy, diversity, and ecology has improved considerably in the past twenty years, but numerous issues still remain. Among these, the diversity and taxonomy of caenagnathids from the Dinosaur Park Formation of Alberta, Canada, have remained problematic. Whereas some authors recognize three genera, others suggest only two were present, and there is considerable disagreement about which specimens are referable to which genus. This study aims to resolve this issue by reviewing the known specimens and using osteohistology, to establish a testable taxonomic framework of Dinosaur Park Formation caenagnathids. Numerous new specimens from all regions of the skeleton provide insight into morphological variation in caenagnathids, and three morphotypes are recognized based on a combination of morphological features and body size. Osteohistology shows that representatives in each body size class are at skeletal maturity, and therefore supports the delineation of three taxa: the smaller Citipes elegans gen. nov., the intermediate Chirostenotes pergracilis, and the larger Caenagnathus collinsi, new material of which shows it rivalled Anzu wyliei in size. However, these analyses also raise concerns about the referral of isolated material to each taxon in the absence of skeletal overlap between specimens or osteohistological analysis. Caenagnathids are consistently recovered throughout the Dinosaur Park Formation interval, and two geographic clusters of increased abundance probably reflect collection and taphonomic biases. The coexistence of three taxa was apparently facilitated by differences in both adult body size and functional morphology of the dentary and pes, which suggests that caenagnathids minimized niche overlap rather than subdividing niche space. Regardless, little is known of the exact roles caenagnathids played in Late Cretaceous ecosystems. Incorporation of the new material and taxonomic framework into a phylogenetic analysis drastically improves our understanding of the relationships between caenagnathines, and sheds light on the evolution of body size in caenagnathids and its role in their diversification.

scholarly journals Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

2014 ◽  
Vol 281 (1797) ◽  
pp. 20142103 ◽  
Author(s):  
Marlee A. Tucker ◽  
Tracey L. Rogers
Keyword(s):  
Community Structure ◽  
Body Size ◽  
Body Mass ◽  
Marine Environment ◽  
Trophic Level ◽  
Marine Mammals ◽  
Trophic Position ◽  
Trophic Levels ◽  
Predator Prey ◽  
Terrestrial Mammals

Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial ( n = 51) and marine ( n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities.

Early Modern Biblical Commentary and Jonathan Edwards

2018 ◽  
Author(s):  
Adriaan C. Neele
Keyword(s):  
New England ◽  
Early Modern ◽  
New World ◽  
Biblical Interpretation ◽  
Jonathan Edwards ◽  
European Continent ◽  
Biblical Commentary ◽  
High Esteem ◽  
Modern Context ◽  
Insight Into

Adriaan C. Neele introduces the early modern context of biblical interpretation by discussing Matthew Poole’s Synopsis Criticorum aliorumque Sacrae Scripturae (1669–1674), a frequently referenced volume for many biblical interpreters, whether in England, on the European continent, or in the New World. Neele shows how this work represents early modern exegesis well and how it became an important channel for bringing medieval commentaries into the hands of post-Reformation exegetes. He also establishes the high esteem that this multivolume work gained in New England and its important role in Jonthan Edwards’ exegesis. The Synopsis gives us insight into early modern interpretation yet also serves as a contrast to New England exegesis, helping us set Edwards in his time.

Fernando Ortiz on Afro-Cuban Music

2017 ◽  
Author(s):  
Robin Moore
Keyword(s):  
20Th Century ◽  
Latin American ◽  
New World ◽  
Academic Career ◽  
Academic Literature ◽  
Fernando Ortiz ◽  
Cuban Studies ◽  
First Time ◽  
American Authors ◽  
Insight Into

Fernando Ortiz is recognized today as one of the most influential Latin American authors of the 20th century. Amazingly prolific, his publications written between the 1890s and the mid-1950s engage with a vast array of subjects and disciplines. Perhaps Ortiz’s most significant accomplishments were the creation of the field of Afro-Cuban studies and major early contributions to the emergent field of Afro-diasporic studies. Almost everyone else associated with similar research began their investigations decades after Ortiz and in dialogue with his work. Ortiz was one of the first to seriously examine slave and post-abolition black cultures in Cuba. His studies became central to new and more positive discourses surrounding African-derived expression in the mid-20th century that embraced it as national expression for the first time in Latin America. This essay considers Ortiz’s academic career and legacy as regards Afro-Cuban musical study beginning in the early 20th century (when his views were quite dated, even racist) and gradual, progressive changes in his attitudes. Ortiz’s work on music and dance have been underrepresented in existing academic literature, despite the fact that most of his late publications focus on such topics and are considered among his most valuable works. His writings on black heritage provide insight into the struggles within New World societies to overcome the racial/evolutionist ideologies that justified colonial subjugation. His scholarship resonates with broader debates throughout the Americas over the meanings of racial pluralism and the legacy of slavery. And his changing views over the years outline the trajectory of modern Western thought as regards Africa and race, specifically the contributions of Afro-diasporic peoples, histories, and cultures to New World societies.

scholarly journals Snap-jaw morphology is specialized for high-speed power amplification in the Dracula ant, Mystrium camillae

2018 ◽  
Vol 5 (12) ◽  
pp. 181447 ◽  
Author(s):  
Fredrick J. Larabee ◽  
Adrian A. Smith ◽  
Andrew V. Suarez
Keyword(s):  
High Speed ◽  
Muscle Power ◽  
Element Analysis ◽  
Predator Prey ◽  
Mantis Shrimp ◽  
Power Amplification ◽  
Form Function ◽  
Function Relationship ◽  
Relationship Of ◽  
Insight Into

What is the limit of animal speed and what mechanisms produce the fastest movements? More than natural history trivia, the answer provides key insight into the form–function relationship of musculoskeletal movement and can determine the outcome of predator–prey interactions. The fastest known animal movements belong to arthropods, including trap-jaw ants, mantis shrimp and froghoppers, that have incorporated latches and springs into their appendage systems to overcome the limits of muscle power. In contrast to these examples of power amplification, where separate structures act as latch and spring to accelerate an appendage, some animals use a ‘snap-jaw’ mechanism that incorporates the latch and spring on the accelerating appendage itself. We examined the kinematics and functional morphology of the Dracula ant, Mystrium camillae , who use a snap-jaw mechanism to quickly slide their mandibles across each other similar to a finger snap. Kinematic analysis of high-speed video revealed that snap-jaw ant mandibles complete their strike in as little as 23 µsec and reach peak velocities of 90 m s −1 , making them the fastest known animal appendage. Finite-element analysis demonstrated that snap-jaw mandibles were less stiff than biting non-power-amplified mandibles, consistent with their use as a flexible spring. These results extend our understanding of animal speed and demonstrate how small changes in morphology can result in dramatic differences in performance.

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