Geographic variation in skin structure in male Andrew’s toad (Bufo andrewsi)

2020 ◽  
Vol 70 (2) ◽  
pp. 159-174
Author(s):  
Can Wang ◽  
Long Jin ◽  
Zhi Ping Mi ◽  
Wen Bo Liao
Keyword(s):  
Water Absorption ◽  
Local Adaptation ◽  
Water Loss ◽  
Geographical Variation ◽  
Single Species ◽  
Complex Environments ◽  
Skin Structure ◽  
Different Populations ◽  
Bufo Andrewsi ◽  
Loose Layer

Abstract Variation in organ structure likely provides important clues on local adaptation and reflects the pressure target of natural selection. As one of the important organs, the skin plays a key role in adapting to complex environments by reducing water loss or increasing water absorption. Nevertheless, variation in the skin structure across different populations in a single species of anurans remains enigmatic. Here, we studied geographical variation in the skin structure of male Andrew’s toads (Bufo andrewsi) across ten populations using histological methods. We quantified thickness of the skin, the epidermis, the loose layer, the compact layer, and of the epidermis, area of granular glands (GGs) and of ordinary mucous glands (OMGs), width of the calcified layer, and number of capillary vessels. We found that the thickness of the skin, dermis and loose layer in dorsal skin increased with latitude whereas the area of granular glands decreased with altitude. Moreover, the width of the calcified layer in ventral skin decreased with latitude among populations. Our findings suggest that geographical variation in skin structure in male B. andrewsi is likely to reduce water loss or make water absorption occur faster in complex high-latitude environments, improving local adaptation.

Water Uptake and Embryonic Development in Eggs of Chorthippus Brunneus Thunberg (Saltatoria: Acrididae)

1969 ◽  
Vol 50 (2) ◽  
pp. 327-333
Author(s):  
F. MORIARTY
Keyword(s):  
Sodium Chloride ◽  
Embryonic Development ◽  
Water Absorption ◽  
Osmotic Pressure ◽  
Water Uptake ◽  
Water Loss ◽  
Chloride Solutions ◽  
Sodium Chloride Solutions ◽  
Close Relationship ◽  
Further Development

1. The pattern of water absorption by eggs of Chorthippus brunneus varies greatly between individuals. 2. The time at which water is absorbed does not have a close relationship with the stage of embryonic development. 3. Water absorption is not essential for prediapause development. 4. Eggs can only undergo blastokinesis and further development, after diapause is broken, if some water has been absorbed. 5. The rate of water loss or gain varies with the osmotic pressure of sodium chloride solutions. 6. Eggs which have started to absorb water appear to become desiccated more rapidly than eggs which have not.

scholarly journals A revision of the Pyura stolonifera species complex (Tunicata, Ascidiacea), with a description of a new species from Australia

Zootaxa ◽  
2011 ◽  
Vol 2754 (1) ◽  
pp. 27 ◽  
Author(s):  
MARC RIUS ◽  
PETER R. TESKE
Keyword(s):  
New Species ◽  
Species Complex ◽  
Taxonomic Status ◽  
Single Species ◽  
Distinct Species ◽  
The Other ◽  
Solitary Ascidian ◽  
Different Populations ◽  
A New Species ◽  
Dorsal Tubercle

Pyura stolonifera is a large solitary ascidian found in Africa, Australasia and South America. The taxonomic status of different populations of this species is disputed, especially since there is evidence for several distinct morphological and genetic units that point towards the existence of multiple cryptic species. While some researchers still recognize P. stolonifera as a single species, others treat the different populations as distinct species. Here, we present a revision of the P. stolonifera species complex based on the examination of samples from all regions where there are reliable reports of this taxon. We recognize four species that are both morphologically and genetically distinct, one of which is new to science and is formally described here. This species is morphologically distinct from the other three members of the species complex in terms of the colour and texture of the tunic, the arrangement of the gonads within the gut and the shape of the dorsal tubercle, among other characters. We name the new species Pyura dalbyi after Dr. J.E. Dalby Jr., whose research on its ecology and distribution provided the incentive for examining this species more closely.

A study of molecular sequences, sexuality, and morphological variation in Plagiomnium carolinianum, P. maximoviczii, and P. rhynchophorum (Bryophyta, Mniaceae)

Phytotaxa ◽  
2018 ◽  
Vol 375 (1) ◽  
pp. 81
Author(s):  
YAN-JUN YI ◽  
ZHEN-WEI SUN ◽  
SI HE ◽  
MAMTIMIN SULAYMAN
Keyword(s):  
Phylogenetic Analyses ◽  
Single Species ◽  
Molecular Study ◽  
Geographic Range ◽  
Similar Species ◽  
Monophyletic Clade ◽  
Closely Related Species ◽  
Molecular Phylogenetic ◽  
Different Populations ◽  
Rps4 Gene

Morphologically, recognition of the genus Plagiomnium may be relatively easy. Yet identifications of closely related species have met great difficulties. The contemporary species delimitations of P. carolinianum, P. maximoviczii, and P. rhynchophorum largely based on sexuality as the sole distinction have not been satisfactory. As shown from literature, character variations among these three taxa were continuous and intergraded within or among different populations throughout a wide geographic range. No gametophytic characters could be reliably used to distinguish them from each other. Molecular phylogenetic analyses using ITS2 and rps4 gene were undertaken to resolve delineations for these three morphologically similar species. The results suggest that they form a well support monophyletic clade, which can be defined as representing one single species with two subspecies, i.e. P. rhynchophorum subsp. maximoviczii and P. rhynchophorum subsp. rhynchophorum. The present molecular study supports the treatment of P. carolinianum as synonym of P. rhynchophorum as purposed previously by Koponen based on morphology.

scholarly journals The costs and benefits of flexibility as an expression of behavioural plasticity: a primate perspective

2013 ◽  
Vol 368 (1618) ◽  
pp. 20120339 ◽  
Author(s):  
Carel P. van Schaik
Keyword(s):  
Environmental Change ◽  
Local Adaptation ◽  
Geographical Variation ◽  
Brain Size ◽  
Behavioural Plasticity ◽  
High Plasticity ◽  
Costs And Benefits ◽  
Cognitive Benefits ◽  
Local Genotypes ◽  
Individual Decisions

Traditional neo-Darwinism ascribes geographical variation in morphology or in behaviour to varying selection on local genotypes. However, mobile and long-lived organisms cannot achieve local adaptation this way, leading to a renewed interest in plasticity. I examined geographical variation in orang-utan subsistence and social behaviour, and found this to be largely owing to behavioural plasticity, here called flexibility, both in the form of flexible individual decisions and of socially transmitted (cultural) innovations. Although comparison with other species is difficult, the extent of such flexibility is almost certainly limited by brain size. It is shown that brains can only increase relative to body size where the cognitive benefits they produce are reliably translated into improved survival rate. This means that organisms that are very small, face many predators, live in highly seasonal environments, or lack opportunities for social learning cannot evolve greater flexibility, and must achieve local adaptation through selection on specific genotypes. On the other hand, as body and brain size increase, local adaptation is increasingly achieved through selection on plasticity. The species involved are also generally those that most need it, being more mobile and longer-lived. Although high plasticity buffers against environmental change, the most flexible organisms face a clear limit because they respond slowly to selection. Thus, paradoxically, the largest-brained animals may actually be vulnerable to the more drastic forms of environmental change, such as those induced by human actions.

Geographical variation in limb muscle mass of the Andrew’s toad (Bufo andrewsi)

2017 ◽  
Vol 67 (1) ◽  
pp. 17-28 ◽  
Author(s):  
Sheng Nan Yang ◽  
Xiao Fu Huang ◽  
Mao Jun Zhong ◽  
Wen Bo Liao
Keyword(s):  
Geographical Variation ◽  
Biceps Femoris ◽  
Relative Mass ◽  
Flexor Carpi Radialis ◽  
Hindlimb Muscles ◽  
Model Animal ◽  
Limb Muscles ◽  
Forelimb Muscles ◽  
Bufo Andrewsi ◽  
Extensor Carpi Radialis

Muscles are vital for the process of movement, mating and escape of predators in amphibians. During evolution, the morphological and genetic characteristics as well as the size of muscles in species will change to adapt different environments. Theory predicts that low male-male competition in high-altitude/latitude selects for small limb muscles. Here, we used the Andrew’s toad (Bufo andrewsi) as a model animal to test this prediction by analyzing geographical variation in the mass of limb muscles across nine populations from the Hengduan Mountains in China. Inconsistent with the prediction, we found that latitude and altitude did not affect the relative mass of total combined limb muscles and mass of combined hindlimb muscles among populations. Meanwhile, the relative mass of combined forelimb muscles, the two forelimb muscles (flexor carpi radialis and extensor carpi radialis) and the four hindlimb muscles (e.g. biceps femoris, semimebranous, semitendinosus and peroneus) was lowest in middle latitude and largest in low latitude whereas gracilis minor was largest in high latitudes. However, we did not find any correlations between the two forelimb muscles and the four hindlimb muscles and altitude. Our findings suggest that combined forelimb muscles, flexor carpi radialis, extensor carpi radialis, biceps femoris, semimebranous, semitendinosus and peroneus are largest in low latitudes due to pressures of mate competition.

A taxonomic revision of the Pyracantha crenulata complex (Rosaceae, Maleae)

Phytotaxa ◽  
2021 ◽  
Vol 478 (2) ◽  
pp. 239-252
Author(s):  
HUI-ZHE FENG ◽  
SU-JUAN WEI ◽  
LONG-YUAN WANG ◽  
SU-FANG CHEN ◽  
QIANG FAN ◽  
...  
Keyword(s):  
Morphological Characteristics ◽  
Taxonomic Revision ◽  
Population Level ◽  
Single Species ◽  
Herbarium Specimens ◽  
Leaf Margin ◽  
Morphological Variations ◽  
Dichotomous Key ◽  
Different Populations ◽  
Distinct Features

Pyracantha is naturally distributed from East Asia to the southeastern Europe regions, and seven species, including five endemic species, were recorded in China. Taxonomic problems within the genus persist, in which the identity of Pyracantha crenulata complex is not clear when referring to the existing species dichotomous key. P. crenulata complex contains three species: P. loureiroi, P. crenulata and P. fortuneana. Such incident might be due to the lack of proper analysis and evaluation of the characters at the population level when first described. To solve this problem, we sampled 48 populations of P. crenulata, examined 278 sheets of herbarium specimens, and conducted principal coordinate analysis (PCoA) on the morphological variations across different populations. Our findings indicated that P. crenulata complex does not display distinct, separated groups based on the morphological characteristics described in the existing species description, the shape of leaf, leaf margin, leaf apices and widest position of leaf are not distinct features for species delimitation in P. crenulata complex. As a result, we proposed that the P. crenulata complex should be recognized as a single species named P. crenulata.

scholarly journals Variation in Metabolic Characteristics of Chrysanthemum indicum from Different Habitats: Implications for cultivation and breeding

2021 ◽  
Author(s):  
Qingjun Zou ◽  
Qiaosheng Guo ◽  
Tao Wang ◽  
Jiamin Chen ◽  
Feng Yang ◽  
...  
Keyword(s):  
Single Species ◽  
Targeted Metabolomics ◽  
Multivariate Statistical ◽  
Metabolic Characteristics ◽  
Flavonoid Synthesis ◽  
Chrysanthemum Indicum ◽  
Widely Targeted Metabolomics ◽  
Application Potential ◽  
Different Populations ◽  
Chemical Products

Abstract Chrysanthemi Indici Flos (CIF), the capitulum of Chrysanthemum indicum, is widely used as Chinese medicine, spice, and tea in many areas, its extracts are also frequently used in daily chemical products and cosmetics. Although CIF-related products are becoming more abundant because of its excellent biological activity, its metabolic characteristics and the accumulation of metabolites are still unclear. A total of 802 metabolites were identified in CIF by widely targeted metabolomics, and significant differences were found in the accumulation of metabolites of CIF from different habitats. Particularly, the differences in metabolite accumulation in CIF were significantly correlated with the geographical distribution in mountainous areas, but not with climate. Through multivariate statistical analysis, the seven samples from different habitats could be divided into four categories, and the significantly changed metabolites between different categories were mainly concentrated in the flavonoid synthesis pathway. Judging from the metabolic level, it was supported to separate the Ch. nankingense (Juhuanao) into a single species. In addition, the corresponding candidate biomarkers were screened in this study to identify the origin of CIF and distinguish the Juhuanao. It can be inferred that widely targeted metabolomics has great application potential in authenticity identification, origin tracing and quality evaluation of CIF. There were abundant metabolic differences among different populations of Ch. indicum, which provided abundant materials for the selection and breeding of fine varieties.

scholarly journals A multilocus assessment reveals two new synonymies for East Asian Cyclommatus stag beetles (Coleoptera, Lucanidae)

ZooKeys ◽  
2021 ◽  
Vol 1021 ◽  
pp. 65-79
Author(s):  
Jiao Jiao Yuan ◽  
Dan Chen ◽  
Xia Wan
Keyword(s):  
Phylogenetic Analyses ◽  
East Asian ◽  
Morphological Variability ◽  
Single Species ◽  
Molecular Data ◽  
Mean Value ◽  
Distance Analysis ◽  
Taiwan Island ◽  
Different Populations ◽  
Stag Beetles

Cyclommatus scutellaris Möllenkamp, 1912, Cyclommatus elsae Kriesche, 1921 and Cyclommatus tamdaoensis Fujita, 2010 are East Asian stag beetle species with long-debated taxonomic relationships due to high intraspecific morphological variability. In this study, we applied multilocus phylogenetic analyses to reassess their relationships. Two mitochondrial genes (16S rDNA, COI) and two nuclear genes (28S rDNA, Wingless) were used to reconstruct the phylogeny through the Bayesian inference (BI) and Maximum Likelihood (ML) methods. Both topologies supported two clades: the clade C. scutellaris was sister to the clade (C. elsae + C. tamdaoensis) with the subclade C. tamdaoensis embedded in the subclade C. elsae. The Kimura 2-parameter (K2P) genetic distance analysis yielded a low mean value (≤0.035) among the three taxa, which was well below the minimum mean value between other Cyclommatus species (≥0.122). We also compared the accuracy and efficiency of two approaches, GMYC and ABGD, in delimitating the three lineages. The result shows that ABGD is a better approach than GMYC. Our molecular data recognizes the three species as different populations of a single species, ranging from Taiwan Island to the continent. Therefore, we propose two new junior synonyms for C. scutellaris: C. tamdaoensis, syn. nov. and C. elsaesyn. nov.

scholarly journals Local adaptation can cause both peaks and troughs in nucleotide diversity within populations

2020 ◽  
Author(s):  
Russ J. Jasper ◽  
Sam Yeaman
Keyword(s):  
Positive Selection ◽  
Local Adaptation ◽  
Nucleotide Diversity ◽  
Single Species ◽  
Population Diversity ◽  
Causal Locus ◽  
Genome Wide ◽  
Theoretical Predictions ◽  
Spatially Extended ◽  
Diagnostic Signature

ABSTRACTLocal adaptation is expected to cause high FST at sites linked to a causal locus, however this pattern can also be driven by background or positive selection. Within-population nucleotide diversity could provide a means to differentiate these scenarios, as both background and positive selection deplete diversity, whereas some theoretical studies have shown that local adaptation increases it. However, it is unclear whether such theoretical predictions generalize to more complicated models. Here, we explore how local adaptation shapes genome-wide patterns in nucleotide diversity and FST, extending previous work to study the effect of variable degrees of polygenicity and genotypic redundancy in an adaptive trait, and different levels of population structure. We show that local adaptation produces two very different patterns depending on the relative strengths of migration and selection, either markedly decreasing or increasing within-population diversity at linked sites at equilibrium. When migration is low, regions of depleted diversity can extend large distances from the causal locus, with substantially more diversity eroded than expected with background selection. With higher migration, peaks occur over much smaller genomic distances but with much larger magnitude changes in diversity. In spatially extended clinal environments both patterns can be found within a single species, with increases in diversity at the center of the range and decreases towards the periphery. Our results demonstrate that there is no universal diagnostic signature of local adaptation based on nucleotide diversity, however, given that neither background nor positive selection inflate diversity, when peaks are found they strongly suggest local adaptation.

Sign in / Sign up

Export Citation Format

Share Document