Ecomorphological analysis of the astragalo-calcaneal complex in rodents and inferences of locomotor behaviours in extinct rodent species

Studies linking postcranial morphology with locomotion in mammals are common. However, such studies are mostly restricted to caviomorphs in rodents. We present here data from various families, belonging to the three main groups of rodents (Sciuroidea, Myodonta, and Ctenohystrica). The aim of this study is to define morphological indicators for the astragalus and calcaneus, which allow for inferences to be made about the locomotor behaviours in rodents. Several specimens were dissected and described to bridge the myology of the leg with the morphology of the bones of interest. Osteological characters were described, compared, mechanically interpreted, and correlated with a “functional sequence” comprising six categories linked to the lifestyle and locomotion (jumping, cursorial, generalist, fossorial, climber and semi-aquatic). Some character states are typical of some of these categories, especially arboreal climbers, fossorial and “cursorial-jumping” taxa. Such reliable characters might be used to infer locomotor behaviours in extinct species. Linear discriminant analyses (LDAs) were used on a wider sample of species and show that astragalar and calcaneal characters can be used to discriminate the categories among extant species whereasa posterioriinferences on extinct species should be examined with caution.

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Cats in the forest: predicting habitat adaptations from humerus morphometry in extant and fossil Felidae (Carnivora)

Paleobiology ◽

10.1666/12001 ◽

2013 ◽

Vol 39 (3) ◽

pp. 323-344 ◽

Cited By ~ 33

Author(s):

Carlo Meloro ◽

Sarah Elton ◽

Julien Louys ◽

Laura C. Bishop ◽

Peter Ditchfield

Keyword(s):

Morphological Variability ◽

Olduvai Gorge ◽

Environmental Predictors ◽

Linear Measurements ◽

Multivariate Statistical ◽

Linear Discriminant ◽

Related Group ◽

Discriminant Analyses ◽

The Stability ◽

The Relationship

Mammalian carnivores are rarely incorporated in paleoenvironmental reconstructions, largely because of their rarity within the fossil record. However, multivariate statistical modeling can be successfully used to quantify specific anatomical features as environmental predictors. Here we explore morphological variability of the humerus in a closely related group of predators (Felidae) to investigate the relationship between morphometric descriptors and habitat categories. We analyze linear measurements of the humerus in three different morphometric combinations (log-transformed, size-free, and ratio), and explore four distinct ways of categorizing habitat adaptations. Open, Mixed, and Closed categories are defined according to criteria based on traditional descriptions of species, distributions, and biome occupancy. Extensive exploratory work is presented using linear discriminant analyses and several fossils are included to provide paleoecological reconstructions.We found no significant differences in the predictive power of distinct morphometric descriptors or habitat criteria, although sample splitting into small and large cat guilds greatly improves the stability of the models. Significant insights emerge for three long-canine cats:Smilodon populator,Paramachairodus orientalis, andDinofelissp. from Olduvai Gorge (East Africa).S. populatorandP. orientalisare both predicted to have been closed-habitat adapted taxa. The false “sabertooth”Dinofelissp. from Olduvai Gorge is predicted to be adapted to mixed habitat. The application of felid humerus ecomorphology to the carnivoran record of Olduvai Gorge shows that the older stratigraphic levels (Bed I, 1.99–1.79 Ma) included a broader range of environments than Beds II or V, where there is an abundance of cats adapted to open environments.

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West Palearctic cobras of the genus Naja (Serpentes: Elapidae): interrelationships among extinct and extant species

Amphibia-Reptilia ◽

10.1163/156853890x00078 ◽

1990 ◽

Vol 11 (4) ◽

pp. 385-400 ◽

Cited By ~ 36

Author(s):

Jean-Claude Rage ◽

Zbigniew Szyndlar

Keyword(s):

Monophyletic Group ◽

Close Relative ◽

African Species ◽

Naja Naja ◽

Extinct Species ◽

Extant Species ◽

Asiatic Species ◽

Extinct Genus

AbstractSome basic osteological cranial features of living and fossil members of the genus Naja are described. The extinct genus Palaeonaja Hoffstetter, 1939, is synonymized with the modern Naja Laurenti, 1768, and the extinct species Palaeonaja crassa Hoffstetter, 1939, is synonymized with Naja romani (Hoffstetter, 1939). Anatomically, the genus Naja can be divided into two main complexes, composed of: (1) living African species, N. antiqua from the Moroccan Miocene, and N. iberica from the Spanish Miocene; (2) living Asiatic species and N. romani from the Miocene of France, Austria, and Ukraine. Living members of the Asiatic complex make up a monophyletic group; they belong to at least three distinct lineages: N. oxiana, N. naja s.s. ( = N. naja naja), and the remaining taxa named here informally the 'East Asiatic Naja'. The African complex is thought to be most primitive and perhaps paraphyletic; Africa is presumed to be the centre of earliest radiation of the genus. The precise relationships of Walterinnesia, a close relative of Naja occupying the area between Asiatic and African ranges of Naja, remain unclear.

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Evolution of body mass in the Pan-Alcidae (Aves, Charadriiformes): the effects of combining neontological and paleontological data

Paleobiology ◽

10.1017/pab.2015.24 ◽

2015 ◽

Vol 42 (1) ◽

pp. 8-26 ◽

Cited By ~ 6

Author(s):

N. Adam Smith

Keyword(s):

Body Mass ◽

Mass Range ◽

Extinct Species ◽

Paleontological Data ◽

Ideal Candidate ◽

Extant Species ◽

Size Evolution ◽

Body Size Evolution ◽

Phylogenetic Hypotheses ◽

Maximum Body

AbstractHypotheses regarding the evolution of many clades are often generated in the absence of data from the fossil record and potential biases introduced by exclusion of paleontological data are frequently ignored. With regard to body size evolution, extinct taxa are frequently excluded because of the lack of body mass estimates—making identification of reliable clade specific body mass estimators crucial to evaluating trends on paleontological timescales. Herein, I identify optimal osteological dimensions for estimating body mass in extinct species of Pan-Alcidae (Aves, Charadriiformes) and utilize newly generated estimates of body mass to demonstrate that the combination of neontological and paleontological data produces results that conflict with hypotheses generated when extant species data are analyzed in isolation. The wing-propelled diving Pan-Alcidae are an ideal candidate for comparing estimates of body mass evolution based only on extant taxa with estimates generated including fossils because extinct species diversity (≥31 species) exceeds extant diversity, includes examples from every extant genera, and because phylogenetic hypotheses of pan-alcid relationships are not restricted to the 23 extant species. Phylogenetically contextualized estimation of body mass values for extinct pan-alcids facilitated evaluation of broad scale trends in the evolution of pan-alcid body mass and generated new data bearing on the maximum body mass threshold for aerial flight in wing-propelled divers. The range of body mass in Pan-Alcidae is found to exceed that of all other clades of Charadriiformes (shorebirds and allies) and intraclade body mass variability is recognized as a recurring theme in the evolution of the clade. Finally, comparisons of pan-alcid body mass range with penguins and the extinct †Plotopteridae elucidate potentially shared constraints among phylogenetically disparate yet ecologically similar clades of wing-propelled divers.

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Factors Discriminating High From Low Score Performance in Biathlon Shooting

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2016-0195 ◽

2017 ◽

Vol 12 (3) ◽

pp. 377-384 ◽

Cited By ~ 17

Author(s):

Gerold Sattlecker ◽

Michael Buchecker ◽

Christoph Gressenbauer ◽

Erich Müller ◽

Stefan J. Lindinger

Keyword(s):

Prone Position ◽

Field Testing ◽

Body Sway ◽

World Cup ◽

Linear Discriminant ◽

Performance Predictors ◽

The World ◽

Discriminant Analyses ◽

Rest Condition ◽

Biomechanical Factors

Purpose:To identify biomechanical predictors that distinguish between high- and low-score athletes in biathlon shooting and to determine the relationships among these variables in field testing.Methods:Twenty-two biathletes (8 female, 14 male) from the World Cup, the European Cup, and a federal youth squad each fired 3 clips of 5 shots in prone and standing shooting positions without physical load, followed by 2 respective series in both disciplines during a simulated 12.5-km pursuit race on roller skis. Biomechanical variables describing triggering, rifle force in the back shoulder, and body and rifle sway were calculated over the last 0.5 second before firing. For computed linear discriminant analyses, subjects were divided into high- and low-level performers based on mean scores for each condition separately. In addition, correlations among all biomechanical factors were calculated.Results:Regarding prone shooting, shoulder force in the rest condition and vertical rifle sway in the race simulation were shown to be main discriminators. Several body- and rifle-sway variables were found to be predictors in standing rest shooting. Body sway across the shooting line discriminated the groups in the standing race situation tendentially. Thus, the main performance predictors changed due to fatigue. Correlations between triggering and rifle sway, shoulder force and rifle sway, and body sway and rifle sway were discovered.Conclusions:Referring to the current results, athletes are recommended to focus on vertical rifle sway in prone position and on body sway across the shooting line during standing shooting when fatigued.

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Lithological control on the landscape form of the upper Rhône Basin, Central Swiss Alps

Earth Surface Dynamics ◽

10.5194/esurf-4-253-2016 ◽

2016 ◽

Vol 4 (1) ◽

pp. 253-272 ◽

Cited By ~ 7

Author(s):

Laura Stutenbecker ◽

Anna Costa ◽

Fritz Schlunegger

Keyword(s):

Swiss Alps ◽

Short Term ◽

Linear Discriminant ◽

Erosion Rates ◽

Digital Elevation ◽

Discriminant Analyses ◽

Controlling Variables ◽

Uplift And Erosion ◽

Landscape Morphology

Abstract. The development of topography depends mainly on the interplay between uplift and erosion. These processes are controlled by various factors including climate, glaciers, lithology, seismic activity and short-term variables, such as anthropogenic impact. Many studies in orogens all over the world have shown how these controlling variables may affect the landscape's topography. In particular, it has been hypothesized that lithology exerts a dominant control on erosion rates and landscape morphology. However, clear demonstrations of this influence are rare and difficult to disentangle from the overprint of other signals such as climate or tectonics. In this study we focus on the upper Rhône Basin situated in the Central Swiss Alps in order to explore the relation between topography, possible controlling variables and lithology in particular. The Rhône Basin has been affected by spatially variable uplift, high orographically driven rainfalls and multiple glaciations. Furthermore, lithology and erodibility vary substantially within the basin. Thanks to high-resolution geological, climatic and topographic data, the Rhône Basin is a suitable laboratory to explore these complexities. Elevation, relief, slope and hypsometric data as well as river profile information from digital elevation models are used to characterize the landscape's topography of around 50 tributary basins. Additionally, uplift over different timescales, glacial inheritance, precipitation patterns and erodibility of the underlying bedrock are quantified for each basin. Results show that the chosen topographic and controlling variables vary remarkably between different tributary basins. We investigate the link between observed topographic differences and the possible controlling variables through statistical analyses. Variations of elevation, slope and relief seem to be linked to differences in long-term uplift rate, whereas elevation distributions (hypsometry) and river profile shapes may be related to glacial imprint. This confirms that the landscape of the Rhône Basin has been highly preconditioned by (past) uplift and glaciation. Linear discriminant analyses (LDAs), however, suggest a stronger link between observed topographic variations and differences in erodibility. We therefore conclude that despite evident glacial and tectonic conditioning, a lithologic control is still preserved and measurable in the landscape of the Rhône tributary basins.

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Cytokine signatures associate with disease severity in children with Mycoplasma pneumoniae pneumonia

Scientific Reports ◽

10.1038/s41598-019-54313-9 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 2

Author(s):

Mingyue Yang ◽

Fanzheng Meng ◽

Man Gao ◽

Genhong Cheng ◽

Xiaosong Wang

Keyword(s):

Disease Severity ◽

Mycoplasma Pneumoniae ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Control Group ◽

Molecular Phenotype ◽

Linear Discriminant ◽

Discriminant Analyses ◽

And Control ◽

Mycoplasma Pneumoniae Pneumonia

AbstractHost immune response may be involved in the pathogenesis of children Mycoplasma pneumoniae pneumonia (MPP). In the current study, we investigated the alterations of cytokines levels among control, mild MPP and severe MPP children to determine whether cytokine signatures associate with MPP and correlate with disease severity. We measured 13 cytokines in bronchoalveolar lavage fluid (BALF) of 88 children with MPP and 26 children with foreign body aspiration (FB) using a Luminex system. Linear discriminant analyses were performed to develop predictive models of mild MPP and severe MPP on these children. We observed nearly complete separations of severe MPP group, mild MPP group and control group in linear discriminant analyses. Eleven cytokines significantly increased in children with MPP, and seven cytokines had statistically significant upward linear trends correlated with MPP severity. In addition, compared to control group, both IFNγ/IL4 ratio and IFNγ/IL13 ratio increased in mild MPP and severe MPP groups. Our results suggest that children MPP can alter BALF cytokines signatures which associate with disease severity and can be characterized by a distinct airway molecular phenotype that has elevated Th1/Th2 ratios.

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Comparative, continuity, and computational evidence in evolutionary theory: Predictive evidence versus productive evidence

Behavioral and Brain Sciences ◽

10.1017/s0140525x06399062 ◽

2006 ◽

Vol 29 (3) ◽

pp. 294-296

Author(s):

David M. W. Powers

Keyword(s):

Evolutionary Theory ◽

Theory Development ◽

Evolutionary Processes ◽

Extinct Species ◽

Extant Species

Of three types of evidence available to evolution theorists – comparative, continuity, and computational – the first is largely productive rather than predictive. Although comparison between extant species or languages is possible and can be suggestive of evolutionary processes, leading to theory development, comparison with extinct species and languages seems necessary for validation. Continuity and computational evidence provide the best opportunities for supporting predictions.

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Paleohaemoproteus burmacis gen. n., sp. n. (Haemospororida: Plasmodiidae) from an Early Cretaceous biting midge (Diptera: Ceratopogonidae)

Parasitology ◽

10.1017/s0031182005007298 ◽

2005 ◽

Vol 131 (1) ◽

pp. 79-84 ◽

Cited By ~ 21

Author(s):

G. POINAR ◽

S. R. TELFORD

Keyword(s):

Early Cretaceous ◽

Malaria Parasite ◽

Developmental Stages ◽

Abdominal Cavity ◽

Malarial Parasite ◽

Fossil Species ◽

Extinct Species ◽

Biting Midge ◽

Extant Species ◽

Wide Range

Paleohaemoproteus burmacis gen. n., sp. n. (Haemospororida: Plasmodiidae) is described from the abdominal cavity of a female biting midge (Diptera: Ceratopogonidae) preserved in 100 million year old amber from Myanmar (Burma). The description is based on the developmental stages of oocysts and sporozoites. The fossil species differs from extant species of Haemoproteus by its wide range of oocyst sizes, small sporozoites and occurrence in an extinct species of biting midge. Numerous sporozoites in the abdominal cavity suggest that the biting midge was an effective vector of this malarial parasite. Characters of the biting midge suggest that the host was a large, cold-blooded vertebrate. This is the earliest record of a malaria parasite and first indication that Early Cretaceous reptiles were infected with haemosporidial parasites.

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Reassembling a lost lowland carabid beetle assemblage (Coleoptera) from Kauai, Hawaiian Islands

Invertebrate Systematics ◽

10.1071/is14047 ◽

2015 ◽

Vol 29 (2) ◽

pp. 191 ◽

Cited By ~ 9

Author(s):

James K. Liebherr ◽

Nick Porch

Keyword(s):

Evolutionary History ◽

Late Holocene ◽

Hawaiian Islands ◽

Cladistic Analysis ◽

Carabid Beetle ◽

Phylogenetic Hypothesis ◽

Extinct Species ◽

Extant Species ◽

Lowland Area ◽

History Of

A late Holocene but prehistoric carabid beetle fauna from the lowland Makauwahi Cave, Kauai, is characterised. Seven extinct species – Blackburnia burneyi, B. cryptipes, B. godzilla, B. menehune, B. mothra, B. ovata and B. rugosa, spp. nov. (tribe Platynini) – represent the first Hawaiian insect species to be newly described from subfossil specimens. Four extant Blackburnia spp. – B. aterrima (Sharp), B. bryophila Liebherr, B. pavida (Sharp), and B. posticata (Sharp) – and three extant species of tribe Bembidiini – Bembidion ignicola Blackburn, B. pacificum Sharp and Tachys oahuensis Blackburn – are also represented. All subfossil fragments are disarticulated, with physical dimensions and cladistic analysis used to associate the major somites – head, prothorax and elytra – for description of the new species. The seven new Makauwahi Cave species support recognition of a lowland area of endemism adjoining Haupu, a low-stature 700 m elevation ridgeline in southern Kauai. Four of the extinct Blackburnia are adelphotaxa to extant species currently found at higher elevations in Kauai. Addition of these lowland specialists to the phylogenetic hypothesis undercuts applicability of the taxon cycle for interpreting evolutionary history of these taxa. Two of the extinct species are Kauai representatives in clades that subsequently colonised younger Hawaiian Islands, enhancing support for the progressive biogeographic colonisation of the archipelago by this lineage. And three of the extinct Blackburnia species comprised larger beetles than those of any extant Kauai Blackburnia, consistent with the evolution of island gigantism in the lowland habitats of Kauai.

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