scholarly journals Pendraig milnerae , a new small-sized coelophysoid theropod from the Late Triassic of Wales

2021 ◽  
Vol 8 (10) ◽  
Author(s):  
Stephan N. F. Spiekman ◽  
Martín D. Ezcurra ◽  
Richard J. Butler ◽  
Nicholas C. Fraser ◽  
Susannah C. R. Maidment
Keyword(s):  
Body Size ◽  
Small Body ◽  
Late Triassic ◽  
Ancestral State ◽  
Dorsal Vertebra ◽  
Left Femur ◽  
Theropod Dinosaur ◽  
Reduced Body ◽  
The Uk ◽  
Fissure Fill

We describe a new small-bodied coelophysoid theropod dinosaur, Pendraig milnerae gen. et sp. nov, from the Late Triassic fissure fill deposits of Pant-y-ffynnon in southern Wales. The species is represented by the holotype, consisting of an articulated pelvic girdle, sacrum and posterior dorsal vertebrae, and an associated left femur, and by two referred specimens, comprising an isolated dorsal vertebra and a partial left ischium. Our phylogenetic analysis recovers P. milnerae as a non-coelophysid coelophysoid theropod, representing the first-named unambiguous theropod from the Triassic of the UK. Recently, it has been suggested that Pant-y-ffynnon and other nearby Late Triassic to Early Jurassic fissure fill faunas might have been subjected to insular dwarfism. To test this hypothesis for P. milnerae , we performed an ancestral state reconstruction analysis of body size in early neotheropods. Although our results indicate that a reduced body size is autapomorphic for P. milnerae , some other coelophysoid taxa show a similar size reduction, and there is, therefore, ambiguous evidence to indicate that this species was subjected to dwarfism. Our analyses further indicate that, in contrast with averostran-line neotheropods, which increased in body size during the Triassic, coelophysoids underwent a small body size decrease early in their evolution.

scholarly journals Mountain colonisation, miniaturisation and ecological evolution in a radiation of direct-developing New Guinea Frogs (Choerophryne, Microhylidae)

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3077 ◽  
Author(s):  
Paul M. Oliver ◽  
Amy Iannella ◽  
Stephen J. Richards ◽  
Michael S.Y. Lee
Keyword(s):  
Body Size ◽  
Small Body ◽  
Strong Support ◽  
New Guinea ◽  
Ancestral State ◽  
Tropical Mountains ◽  
Climatic Oscillations ◽  
Evolutionary Trajectories ◽  
Montane Biodiversity ◽  
Male Calling

AimsMountain ranges in the tropics are characterised by high levels of localised endemism, often-aberrant evolutionary trajectories, and some of the world’s most diverse regional biotas. Here we investigate the evolution of montane endemism, ecology and body size in a clade of direct-developing frogs (Choerophryne,Microhylidae) from New Guinea.MethodsPhylogenetic relationships were estimated from a mitochondrial molecular dataset using Bayesian and maximum likelihood approaches. Ancestral state reconstruction was used to infer the evolution of elevational distribution, ecology (indexed by male calling height), and body size, and phylogenetically corrected regression was employed to examine the relationships between these three traits.ResultsWe obtained strong support for a monophyletic lineage comprising the majority of taxa sampled. Within this clade we identified one subclade that appears to have diversified primarily in montane habitats of the Central Cordillera (>1,000 m a.s.l.), with subsequent dispersal to isolated North Papuan Mountains. A second subclade (characterised by moderately to very elongated snouts) appears to have diversified primarily in hill forests (<1,000 m a.s.l.), with inferred independent upwards colonisations of isolated montane habitats, especially in isolated North Papuan Mountains. We found no clear relationship between extremely small body size (adult SVL less than 15 mm) and elevation, but a stronger relationship with ecology—smaller species tend to be more terrestrial.ConclusionsOrogeny and climatic oscillations have interacted to generate high montane biodiversity in New Guinea via both localised diversification within montane habitats (centric endemism) and periodic dispersal across lowland regions (eccentric endemism). The correlation between extreme miniaturisation and terrestrial habits reflects a general trend in frogs, suggesting that ecological or physiological constraints limit niche usage by miniaturised frogs, even in extremely wet environments such as tropical mountains.

scholarly journals Mountain colonisation, miniaturisation and ecological evolution in a radiation of direct developing New Guinea Frogs (Choerophryne, Microhylidae)

2017 ◽  
Author(s):  
Paul M Oliver ◽  
Amy Iannella ◽  
Stephen J Richards ◽  
Michael S.Y Lee
Keyword(s):  
Body Size ◽  
Small Body ◽  
Strong Support ◽  
New Guinea ◽  
Ancestral State ◽  
Tropical Mountains ◽  
Climatic Oscillations ◽  
Evolutionary Trajectories ◽  
Montane Biodiversity ◽  
Male Calling

Aims. Mountain ranges in the tropics are characterised by high levels of localised endemism, often-aberrant evolutionary trajectories, and some of the world’s most diverse regional biotas. Here we investigate the evolution of montane endemism, ecology and body size in a clade of direct-developing frogs (Choerophryne, Microhylidae) from New Guinea. Methods. Phylogenetic relationships were estimated from a mitochondrial molecular dataset using Bayesian and maximum likelihood approaches. Ancestral state reconstruction was used to infer the evolution of elevational distribution, ecology (indexed by male calling height), and body size, and phylogenetically corrected regression was employed to examine the relationships between these three traits. Results. We obtained strong support for a monophyletic lineage comprising the majority of taxa sampled. Within this clade we identified one subclade that appears to have diversified primarily in montane habitats of the Central Cordillera (> 1000 m. a.s.l), with subsequent dispersal to isolated North Papuan Mountains. A second subclade (characterised by moderately to very elongated snouts) appears to have diversified primarily in hill forests (< 1000 m a.s.l.), with inferred independent upwards colonisations of isolated montane habitats, especially in isolated North Papuan Mountains. We found no clear relationship between extremely small body size (adult SVL less than 15mm) and elevation, but a stronger relationship with ecology – smaller species tend to be more terrestrial. Conclusions. Orogeny and climatic oscillations have interacted to generate high montane biodiversity in New Guinea via both localised diversification within montane habitats (centric endemism) and periodic dispersal across lowland regions (eccentric endemism). The correlation between extreme miniaturisation and terrestrial habits reflects a general trend in frogs, suggesting that ecological or physiological constraints limit niche usage by miniaturised frogs, even in extremely wet environments such as tropical mountains.

scholarly journals Mountain colonisation, miniaturisation and ecological evolution in a radiation of direct developing New Guinea Frogs (Choerophryne, Microhylidae)

2017 ◽  
Author(s):  
Paul M Oliver ◽  
Amy Iannella ◽  
Stephen J Richards ◽  
Michael S.Y Lee
Keyword(s):  
Body Size ◽  
Small Body ◽  
Strong Support ◽  
New Guinea ◽  
Ancestral State ◽  
Tropical Mountains ◽  
Climatic Oscillations ◽  
Evolutionary Trajectories ◽  
Montane Biodiversity ◽  
Male Calling

Aims. Mountain ranges in the tropics are characterised by high levels of localised endemism, often-aberrant evolutionary trajectories, and some of the world’s most diverse regional biotas. Here we investigate the evolution of montane endemism, ecology and body size in a clade of direct-developing frogs (Choerophryne, Microhylidae) from New Guinea. Methods. Phylogenetic relationships were estimated from a mitochondrial molecular dataset using Bayesian and maximum likelihood approaches. Ancestral state reconstruction was used to infer the evolution of elevational distribution, ecology (indexed by male calling height), and body size, and phylogenetically corrected regression was employed to examine the relationships between these three traits. Results. We obtained strong support for a monophyletic lineage comprising the majority of taxa sampled. Within this clade we identified one subclade that appears to have diversified primarily in montane habitats of the Central Cordillera (> 1000 m. a.s.l), with subsequent dispersal to isolated North Papuan Mountains. A second subclade (characterised by moderately to very elongated snouts) appears to have diversified primarily in hill forests (< 1000 m a.s.l.), with inferred independent upwards colonisations of isolated montane habitats, especially in isolated North Papuan Mountains. We found no clear relationship between extremely small body size (adult SVL less than 15mm) and elevation, but a stronger relationship with ecology – smaller species tend to be more terrestrial. Conclusions. Orogeny and climatic oscillations have interacted to generate high montane biodiversity in New Guinea via both localised diversification within montane habitats (centric endemism) and periodic dispersal across lowland regions (eccentric endemism). The correlation between extreme miniaturisation and terrestrial habits reflects a general trend in frogs, suggesting that ecological or physiological constraints limit niche usage by miniaturised frogs, even in extremely wet environments such as tropical mountains.

scholarly journals Mountain colonisation, miniaturisation and ecological evolution in a radiation of direct developing New Guinea Frogs (Choerophryne, Microhylidae)

2016 ◽  
Author(s):  
Paul M Oliver ◽  
Amy Iannella ◽  
Stephen J Richards ◽  
Michael S.Y Lee
Keyword(s):  
Body Size ◽  
Small Body ◽  
Strong Support ◽  
New Guinea ◽  
Ancestral State ◽  
Tropical Mountains ◽  
Climatic Oscillations ◽  
Evolutionary Trajectories ◽  
Montane Biodiversity ◽  
Male Calling

Aims. Mountain ranges in the tropics are characterised by high levels of localised endemism, often-aberrant evolutionary trajectories, and some of the world’s most diverse regional biotas. Here we investigate the evolution of montane endemism, ecology and body size in a clade of direct-developing frogs (Choerophryne, Microhylidae) from New Guinea. Methods. Phylogenetic relationships were estimated from a mitochondrial molecular dataset using Bayesian and maximum likelihood approaches. Ancestral state reconstruction was used to infer the evolution of elevational distribution, ecology (indexed by male calling height), and body size, and phylogenetically corrected regression was employed to examine the relationships between these three traits. Results. We obtained strong support for a monophyletic lineage comprising the majority of taxa sampled. Within this clade we identified one subclade that appears to have diversified primarily in montane habitats of the Central Cordillera (> 1000 m. a.s.l), with subsequent dispersal to isolated North Papuan Mountains. A second subclade (characterised by moderately to very elongated snouts) appears to have diversified primarily in hill forests (< 1000 m a.s.l.), with inferred independent upwards colonisations of isolated montane habitats, especially in isolated North Papuan Mountains. We found no clear relationship between extremely small body size (adult SVL less than 15mm) and elevation, but a stronger relationship with ecology – smaller species tend to be more terrestrial. Conclusions. Orogeny and climatic oscillations have interacted to generate high montane biodiversity in New Guinea via both localised diversification within montane habitats (centric endemism) and periodic dispersal across lowland regions (eccentric endemism). The correlation between extreme miniaturisation and terrestrial habits reflects a general trend in frogs, suggesting that ecological or physiological constraints limit niche usage by miniaturised frogs, even in extremely wet environments such as tropical mountains.

scholarly journals CDK5RAP2 loss-of-function causes premature cell senescence via the GSK3β/β-catenin-WIP1 pathway

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Xidi Wang ◽  
Patrick Sipila ◽  
Zizhen Si ◽  
Jesusa L. Rosales ◽  
Xu Gao ◽  
...  
Keyword(s):  
Body Size ◽  
Developmental Disorders ◽  
Target Genes ◽  
Small Body ◽  
Human Fibroblasts ◽  
Cell Senescence ◽  
Loss Of Function ◽  
Embryonic Fibroblasts ◽  
Senescent Phenotype ◽  
Reduced Body

AbstractDevelopmental disorders characterized by small body size have been linked to CDK5RAP2 loss-of-function mutations, but the mechanisms underlying which remain obscure. Here, we demonstrate that knocking down CDK5RAP2 in human fibroblasts triggers premature cell senescence that is recapitulated in Cdk5rap2an/an mouse embryonic fibroblasts and embryos, which exhibit reduced body weight and size, and increased senescence-associated (SA)-β-gal staining compared to Cdk5rap2+/+ and Cdk5rap2+/an embryos. Interestingly, CDK5RAP2-knockdown human fibroblasts show increased p53 Ser15 phosphorylation that does not correlate with activation of p53 kinases, but rather correlates with decreased level of the p53 phosphatase, WIP1. Ectopic WIP1 expression reverses the senescent phenotype in CDK5RAP2-knockdown cells, indicating that senescence in these cells is linked to WIP1 downregulation. CDK5RAP2 interacts with GSK3β, causing increased inhibitory GSK3β Ser9 phosphorylation and inhibiting the activity of GSK3β, which phosphorylates β-catenin, tagging β-catenin for degradation. Thus, loss of CDK5RAP2 decreases GSK3β Ser9 phosphorylation and increases GSK3β activity, reducing nuclear β-catenin, which affects the expression of NF-κB target genes such as WIP1. Consequently, loss of CDK5RAP2 or β-catenin causes WIP1 downregulation. Inhibition of GSK3β activity restores β-catenin and WIP1 levels in CDK5RAP2-knockdown cells, reducing p53 Ser15 phosphorylation and preventing senescence in these cells. Conversely, inhibition of WIP1 activity increases p53 Ser15 phosphorylation and senescence in CDK5RAP2-depleted cells lacking GSK3β activity. These findings indicate that loss of CDK5RAP2 promotes premature cell senescence through GSK3β/β-catenin downregulation of WIP1. Premature cell senescence may contribute to reduced body size associated with CDK5RAP2 loss-of-function.

scholarly journals Variants in FtsJ RNA 2′-O-Methyltransferase 3 and Growth Hormone 1 are associated with small body size and a dental anomaly in dogs

2020 ◽  
Vol 117 (40) ◽  
pp. 24929-24935
Author(s):  
Sydney R. Abrams ◽  
Alexandra L. Hawks ◽  
Jacquelyn M. Evans ◽  
Thomas R. Famula ◽  
Mary Mahaffey ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Body Size ◽  
Association Studies ◽  
Small Body ◽  
Chromosome 9 ◽  
Genome Wide Association Studies ◽  
Canine Tooth ◽  
Human Pituitary ◽  
Reduced Body

Domesticated dogs show unparalleled diversity in body size across breeds, but within breeds variation is limited by selective breeding. Many heritable diseases of dogs are found among breeds of similar sizes, suggesting that as in humans, alleles governing growth have pleiotropic effects. Here, we conducted independent genome-wide association studies in the small Shetland Sheepdog breed and discovered a locus on chromosome 9 that is associated with a dental abnormality called maxillary canine-tooth mesioversion (MCM) (P = 1.53 × 10−7) as well as two body size traits: height (P = 1.67 × 10−5) and weight (P = 1.16 × 10−7). Using whole-genome resequencing data, we identified variants in two proximal genes: FTSJ3, encoding an RNA methyltransferase, and GH1, encoding growth hormone. A substitution in FTSJ3 and a splice donor insertion in GH1 are strongly associated with MCM and reduced body size in Shetland Sheepdogs. We demonstrated in vitro that the GH1 variant leads to exon 3 skipping, predicting a mutant protein known to cause human pituitary dwarfism. Statistical modeling, however, indicates that the FTSJ3 variant is the stronger predictor of MCM and that each derived allele reduces body size by about 1 inch and 5 pounds. In a survey of 224 breeds, both FTSJ3 and GH1 variants are frequent among very small “toy” breeds and absent from larger breeds. Our findings indicate that a chromosome 9 locus harboring tightly linked variants in FTSJ3 and GH1 reduces growth in the Shetland Sheepdog and toy breed dogs and confers risk for MCM through vertical pleiotropy.

Effects of low pH and aluminum on body size, swimming performance, and susceptibility to predation of green tree frog (Hyla cinerea) tadpoles

1995 ◽  
Vol 73 (12) ◽  
pp. 2171-2183 ◽  
Author(s):  
Robin E. Jung ◽  
Charles H. Jagoe
Keyword(s):  
Body Size ◽  
Swimming Performance ◽  
Small Body ◽  
Low Ph ◽  
Analysis Of Covariance ◽  
Tree Frog ◽  
Small Body Size ◽  
Hyla Cinerea ◽  
Reduced Body ◽  
Sublethal Concentrations

Green tree frog (Hyla cinerea) tadpoles were exposed immediately after hatching to aluminum (nominally 0, 150, 250, 400 μg/L) at pH 4.5 or 5.5, plus a control (pH 7.0, 0 μg/L Al) for 96 h. Mortality increased with increasing Al concentration at pH 4.5 but not at pH 5.5. Among surviving tadpoles, body size was significantly reduced at higher Al concentrations at both pH 4.5 and 5.5. At pH 4.5, analysis of covariance indicated that maximal swimming speed was positively correlated with tadpole total length and differed among Al treatments; tadpoles at higher Al levels swam more slowly. Body Al and Na+concentrations also differed among treatments. In a second experiment, tadpoles exposed for 96 h to approximately 150 μg/L Al at 4.5 pH were preyed upon by dragonfly larvae (Libellulidae) at a higher rate than were tadpoles raised in pH 4.5 or 7.0 without Al. As in the first experiment, tadpoles exposed to Al were smaller and were slower swimmers. Sublethal concentrations of Al at low pH may result in lowered growth rates and hence reduced body size. Swimming performance is reduced by small body size, and size-adjusted performance is further reduced by Al and low pH, which might lead to higher predation on Al-stressed tadpoles.

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