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2021 ◽  
Vol 906 (1) ◽  
pp. 012005
Author(s):  
Vladimir Shkodzinskiy

Abstract The obtained numerous proofs of hot heterogeneous accretion of the Earth lead to a fundamentally new solution to the problems of genesis and evolution of magmas. According to these data, the Earth’s core was formed earlier than the silicate mantle as a result of the agglutination of iron particles of the protoplanetary disk under the influence of magnetic forces, because with a small body size, these forces were billions of times more powerful thangravitational ones. The accretion of the silicate mantle created a global magmatic ocean under the influence of impact heat release. Its bottom part crystallized and fractionated as a result of the pressure increase of the formed upper parts. Cumulates formed the ultrabasic mantle, and residual melts formed the magmatic ocean. The increase in ocean temperature and depth caused the evolution of bottom residual melts from acidic to ultrabasic, the appearance of corresponding layers in the ocean, and the reverse geothermal gradient in the mantle. As a result of the cooling and crystallization of the ocean from top to bottom after 3.8 billion years ago early Precambrian crystal complexes, acidic crust, and the lithosphere of ancient platforms were formed. The separation of residual melts from various layers caused the evolution of magmatism on them from acidic to akaline-ultramafic and kimberlite. Heating of the mantle by a high-temperature core led to the appearance of a direct geothermal gradient at the end of the Proterozoic, convection in the mantle, and modern geodynamic environments. In them, magmas are formed by the frictional and decompression melting of the differentiates of the magmatic ocean.


2021 ◽  
Author(s):  
Michel Schmidt ◽  
Xianguang Hou ◽  
Dayou Zhai ◽  
Huijuan Mai ◽  
Jelena Belojevic ◽  
...  

The Cambrian Stage 3 Chengjiang biota in South China is one of the most influential Konservat Lagerstatten worldwide thanks to the fossilization of diverse nonbiomineralizing organisms through pyritization. Despite their contributions to understanding the evolution of early animals, several Chengjiang species remain poorly known due to their scarcity and/or incomplete preservation. Here, we use micro-computed tomography to reveal in detail the ventral appendage organization of the enigmatic non-trilobite artiopod Pygmaclypeatus daziensis, one of the rarest euarthropods in Chengjiang, and explore its functional ecology and broader evolutionary significance. P. daziensis possesses a set of uniramous antennae and 14 pairs of post-antennal biramous appendages, the latter of which show an unexpectedly high degree of heteronomy based on the localized differentiation of the protopodite, endopod and exopod along the antero-posterior body axis. The small body size (less than 2 cm), presence of delicate spinose endites, and well-developed exopods with multiple paddle-shaped lamellae on the appendages of P. daziensis indicate a nekto-benthic mode of life, and a scavenging/detritus feeding strategy. P. daziensis shows that appendage heteronomy is phylogenetically widespread within Artiopoda, the megadiverse clade that includes trilobites and their relatives with nonbiomineralizing exoskeletons and suggests that a single exopod lobe with paddle like lamellae is ancestral for this clade.


Herpetozoa ◽  
2021 ◽  
Vol 34 ◽  
pp. 131-140
Author(s):  
Shuo Liu ◽  
Mian Hou ◽  
Mingzhong Mo ◽  
Dingqi Rao

A new species of the genus Micryletta Dubois, 1987 is described from Yunnan Province, China, based on morphological and molecular analyses. The most obvious differences between the new species and other species of this genus are small body size, unique coloration, and relatively longer hind limbs. In 16S rRNA gene sequences, the new species is diverged from all other congeners by 3.1%–8.0%.


Author(s):  
A Uemura ◽  
L Hamabe ◽  
R Tanaka

Dog barking, which reaches around 100 dB, often becomes a noise issue in urban environments. One potential solution, a simple soundproof cage, has recently been marketed. To our knowledge, no study has been conducted to investigate what sort of stress burden is imposed on dogs kept in cages, and it may raise animal welfare concerns. The purpose of this study was, therefore, to reveal whether staying in a soundproof cage caused stress for the dogs or not. Ten healthy domestic dogs (5 males, 5 females) of small body size were evaluated. The heart rate variability (HRV), behaviour, and internal and external temperature during confinement in a soundproof cage for each dog were analysed. The HRV analyses revealed no significant differences for any variables between confinement and non-confinement (HR, P > 0.999 9; rMSSD, P = 0.359 4; SDNN, P = 0.359 4; LF, P = 0.652 3; HF, P = 0.128 9; LF/HF, P = 0.222 7). Overall, in our behavioural analysis, there were no significant differences between confinement and non-confinement (P = 0.105 5). In conclusion, the HRV and behavioural analyses did not indicate an increased stress burden on the dogs during confinement in the soundproof cage compared with non-confinement. The inner temperature of the cage was not elevated either. Nevertheless, the stress imposed on dogs caused by a soundproof cage should always be considered on an individual basis, and the time spent in such a cage should always be kept to a minimum.


2021 ◽  
Author(s):  
Izabela Jędrzejowska ◽  
Jana Christophoryová ◽  
Arnold Garbiec
Keyword(s):  

Zootaxa ◽  
2021 ◽  
Vol 4969 (2) ◽  
pp. 331-350
Author(s):  
AKSHAY KHANDEKAR ◽  
TEJAS THACKERAY ◽  
ISHAN AGARWAL

We describe a distinct new rupicolous Cnemaspis based on four adult specimens collected from the Kedareshwar caves on Harishchandragad mountain, from the northern Western Ghats, approximately 1200 m asl. in Ahmednagar district of Maharashtra state, India. Cnemaspis uttaraghati sp. nov. can be diagnosed from all other peninsular Indian congeners by its small body size (maximum SVL < 39 mm), heterogeneous dorsal pholidosis, presence of spine-like tubercles on flanks; presence of only femoral pores in males; tail with enlarged, strongly keeled, conical tubercles forming whorls; median row of sub-caudal scales smooth, slightly enlarged, regularly arranged with condition of two slightly larger scales alternating with a large divided scale. The new species is likely to be allied to the C. girii clade and can be diagnosed from its members by its slightly larger body size, presence of spine-like tubercles on flanks, the number of enlarged tubercles in paravertebral rows between forelimb and hindlimb insertions, the number of dorsal tubercle rows at mid-body, the number of ventral scales across belly at mid-body, the number of longitudinal ventral scales from mental to cloaca, and the number of lamellae under digit IV of manus. We also provide a detailed morphological dataset for C. goaensis and C. indraneildasii based on topotypic material and specimens collected from additional localities to confirm C. indraneildasii is a junior synonym of C. goaensis, and provide an updated diagnosis for C. goaensis. 


Zootaxa ◽  
2021 ◽  
Vol 4952 (1) ◽  
pp. 181-191
Author(s):  
VAN QUANG VO ◽  
HSUAN-CHING HO ◽  
HA VIET DAO ◽  
HOA HONG THI TRAN

Meadia minor sp. nov., a scaless ilyophine eel, is described on the basis of 10 specimens collected from off Quy Nhon, central coast of Vietnam. It can be distinguished from its congeners in having a relatively long trunk (21.3–25.0% TL) which is longer than head length; a short and blunt snout (21.4–23.7% HL); gill opening close to pectoral-fin base; interbranchial space broad (20.7–26.2% HL); dorsal-fin origin above posterior third of pectoral fin; body depth 24–28 times in TL; total vertebrae 118–122; mean vertebral formula 7-33-121; and a small body size, reaching 330 mm TL. The generic status of the new species is discussed. Short descriptions of two congeners are provided. 


2021 ◽  
Vol 9 ◽  
Author(s):  
Jan Wölfer ◽  
Tina Aschenbach ◽  
Jenny Michel ◽  
John A. Nyakatura

Differences between arboreal and terrestrial supports likely pose less contrasting functional demands on the locomotor system at a small body size. For arboreal mammals of small body size, asymmetrical gaits have been demonstrated to be advantageous to increase dynamic stability. Many of the extant arboreal squirrel-related rodents display a small body size, claws on all digits, and limited prehensility, a combination that was proposed to have characterized the earliest Euarchontoglires. Thus, motion analysis of such a modern analog could shed light onto the early locomotor evolution of eurarchontoglirans. In this study, we investigated how Swinhoe’s striped squirrels (Tamiops swinhoei; Scuiromorpha) adjust their locomotion when faced with different orientations on broad supports and simulated small branches. We simultaneously recorded high-Hz videos (501 trials) and support reaction forces (451 trials) of squirrels running on two types of instrumented trackways installed at either a 45° incline (we recorded locomotion on inclines and declines) or with a horizontal orientation. The striped squirrels almost exclusively used asymmetrical gaits with a preference for full bounds. Locomotion on simulated branches did not differ substantially from locomotion on the flat trackway. We interpreted several of the quantified adjustments on declines and inclines (in comparison to horizontal supports) as mechanisms to increase stability (e.g., by minimizing toppling moments) and as adjustments to the differential loading of fore- and hind limbs on inclined supports. Our data, in addition to published comparative data and similarities to the locomotion of other small arboreal rodents, tree shrews, and primates as well as a likely small body size at the crown-group node of Euarchontoglires, render a preference for asymmetrical gaits in early members of the clade plausible. This contributes to our understanding of the ancestral lifestyle of this mammalian ‘superclade’.


Zootaxa ◽  
2021 ◽  
Vol 4950 (3) ◽  
pp. 501-527
Author(s):  
AKSHAY KHANDEKAR ◽  
TEJAS THACKERAY ◽  
ISHAN AGARWAL

We describe a new small-bodied, polymorphic Cnemaspis from near Hongadahalla village, Sakleshpur in the Central Western Ghats of Karnataka, India. Cnemaspis schalleri sp. nov. is allied to C. monticola and can be diagnosed from all other Indian Cnemaspis by its small body size; presence of spine-like tubercles on flank; heterogeneous dorsal pholidosis; presence of both precloacal and femoral pores in males; dorsal pholidosis of tail heterogeneous, composed of small, weakly keeled, flattened, sub-imbricate scales intermixed with enlarged, strongly keeled, distinctly pointed, conical tubercles forming whorls; slightly enlarged median row of sub-caudal scales, smooth at anterior half and strongly keeled posteriorly. The new species differs from C. monticola based on the number of dorsal tubercle rows at mid-body, the number of paravertebral tubercles, the number of precloacal pores and poreless scales between precloacal and femoral pores; besides 8.9–10.7 % uncorrected ND2 sequence divergence. We also provide the first description of topotypic males of C. monticola along with the first data on live colouration and natural history. Cnemaspis schalleri sp. nov. is the second new Cnemaspis described from around Sakleshpur within a span of less than a year with minimal field survey effort. It is almost certain than the dedicated systematic sampling across the Central Western Ghats will result in the discovery of many undescribed Cnemaspis lineages. 


2021 ◽  
Vol 5 (1) ◽  
pp. 25-38
Author(s):  
Amit Sayyed ◽  
Vivek Philip Cyriac ◽  
Anish Pardeshi ◽  
Shauri Sulakhe

A new species of the genus Cnemaspis Strauch, 1887 is described from the Rajgad fort in the northern Western Ghats of Maharashtra, India. The new species, belonging to the flaviventralis clade, is one of the smallest known Indian Cnemaspis and can be distinguished from other congeners by its genetic distinctiveness and few key morphological characters. The new species can be diagnosed from all other Indian congeners by its small body size (SVL &lt; 27 mm), the absence of conical and spine-like tubercles on flank; heterogeneous dorsal pholidosis; presence of only femoral pores and no precloacal pores in males; weakly keeled scales on the ventral surface of neck, pectoral, abdominal region and limbs; granular scales on the tail with whorls of slightly enlarged, strongly keeled tubercles; and the absence of enlarged median subcaudal scales. The new species is currently known to inhabit the man-made historical structures from a single locality in Rajgad, Maharashtra, where it is presumed to be uncommon.


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