species selection
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Thiago Bernardi Vieira ◽  
Liriann Chrisley Da Silva ◽  
Jessica Silva ◽  
Lilian Casatti ◽  
Renato de Romero ◽  

The Species-Sorting concept, one of the models developed to explain patterns in metacommunity structure, suggests that relationships between biological communities and environmental conditions is the basic means of the species selection processes. A second concept is Neutral Theory, and the idea of neutral dynamics underpinning metacommunity structure, cannot be overlooked. The third mechanism is the Mass-Effect concept, that focuses on the interaction between environmental condition and neutral effects. In the present study, we partitioned fish communities in streams between niche and neutral theory concepts, identifying the best representation of metacommunity structure, and assessed if linear and hydrographic distance were equivalent in the representation of neutral processes. The result points to the importance of species sorting mechanisms in structuring fish communities with neutral processes best represented by the linear distances. These results are important for the fish fauna conservation leading to three considerations: (i) the variation of the landscape and habitat is important for the stream fish, (ii) the natural barriers are an important landscape component to be considered, and (iii) the artificial barriers (dams and impoundments) need to be planned taking in account the catchment basin as the landscape unit.

2022 ◽  
Vitor de Andrade Kamimura ◽  
Gabriel Mendes Marcusso ◽  
Gabriel Pavan Sabino ◽  
Marco Antonio Assis ◽  
Carlos Alfredo Joly ◽  

Abstract Unveiling the ecological processes driving diversity and its relationship to the environment remains a central goal in ecological studies. Here, we investigated the elevation effect on plant diversity patterns of tropical rainforests, using beta-, phylogenetic and alpha diversities. To do so, we compiled a forest dataset with 22,236 trees (DBH ≥ 4.8 cm) from 17 plots of 1 ha each along an elevational gradient (0 – 1,200 m a.s.l) in the Atlantic Forest of Southeastern Brazil. We found high phylogenetic and species rates of turnover – beta-diversity - along the elevational gradient. Alpha phylodiversity showed a monotonic decrease with increasing elevation, including or not fern species (a distantly related clade usually ignored in tropical ecology studies), while the phylogenetic structure was highly affected by the inclusion of fern trees. Species diversity showed a unimodal pattern for the whole community, and different patterns for the richest families. The diversity pattern of the whole community emerges from differences among species distribution of the richest families, while phylogenetic diversity seems to be gradually filtered by elevation. At intermediate elevations, higher species diversification within families might have led to different strategies and cooccurrence in tropical rainforests. We also showed that intricate effects of elevation in species assemblages can be better assessed using both ecological and evolutionary approaches, stressing the importance of species selection in diversity analyzes. Finally, we demonstrate that elevation has different effects on the species distributions of the richest families and warn that these differences should be considered in conservation planning.

2022 ◽  
Alijon Xusanov

Diversity of ecological niches among aphid entomocenosis increased, most likely, in the process of evolution, due to unsuitability for one or two species selection in the direction of direct competition compared with the advantage of selection in the direction of differentiation niches, reliable provision of resources of different types in terms of maintaining of both species and the relative independence from the competition with other species for resources of host plants....

Ying Ki Law ◽  
Calvin Lee ◽  
Chun Chiu Pang ◽  
Billy Hau ◽  
Jin Wu

Landslides are common in tropical and subtropical regions with hilly terrains and heavy rainstorms, which cause significant economic, ecological, and social impacts. Natural forest succession is usually slow on landslide scars due to poor soil structure and the lack of seeds of woody plant seeds, and often comes with a higher risk of repeated landslide. Ecological forest restoration has recently been suggested as an effective alternative to restore the exposed landslide scars, however, a comprehensive study to identify effective landslide restoration strategies remains lacking, particularly associated with seed treatment methods and species selection. Here we evaluated the effectiveness of different seed coating treatments of both pioneer and later successional tree species of different seed sizes on seed germination in a one-year study on three landslides in Hong Kong. Our results show that bare seeds had germination rates of 17 to 67% across all selected species (n=7). Biochar-dominant seed coating formulation boosted an additional 9.33 (SE= 0.04) in seed germination rate, while the clay-dominant seed coating formulation did not show significant effect on germination. Our results also show that medium and large-seeded non-pioneer species have significantly higher germination rates than pioneer species. These results collectively suggest that direct seeding using a biochar seed coat is a manageable and useful method to enhance tree seed germination—an essential first step to restore the forests after landslide disturbances in Hong Kong, with potential to be extended to other humid tropical and subtropical forests.

2022 ◽  
Miguel R Chuapoco ◽  
Nicholas Flytzanis ◽  
Nick Goeden ◽  
J Christopher Octeau ◽  
Kristina M Roxas ◽  

Adeno-associated viruses (AAVs) can enable robust and safe gene delivery to the mammalian central nervous system (CNS). While the scientific community has developed numerous neurotropic AAV variants for systemic gene-transfer to the rodent brain, there are few AAVs that efficiently access the CNS of higher order primates. We describe here AAV.CAP-Mac, an engineered AAV variant that enables systemic, brain-wide gene delivery in infants of two Old World primate species--the rhesus macaque (Macaca mulatta) and the green monkey (Chlorocebus sabaeus). We identified CAP-Mac using a multi-species selection strategy, initially screening our library in the adult common marmoset (Callithrix jacchus) and narrowing our pool of test-variants for another round of selection in infant macaques. In individual characterization, CAP-Mac robustly transduces human neurons in vitro and Old World primate neurons in vivo, where it targets all lobes of cortex, the cerebellum, and multiple subcortical regions of disease relevance. We use CAP-Mac for Brainbow-like multicolor labeling of macaque neurons throughout the brain, enabling morphological reconstruction of both medium spiny neurons and cortical pyramidal cells. Because of its broad distribution throughout the brain and high neuronal efficiency in infant Old World primates compared to AAV9, CAP-Mac shows promise for researchers and clinicians alike to unlock novel, noninvasive access to the brain for efficient gene transfer.

2022 ◽  
Vol 8 ◽  
Bavo De Witte ◽  
Ana I. Catarino ◽  
Loes Vandecasteele ◽  
Michael Dekimpe ◽  
Nelle Meyers ◽  

Monitoring the occurrence and trends of microplastic contamination in the marine environment is key to establish microplastic (MP) data baselines, to work out policy mitigation measures, and to assess the effectiveness of waste regulations. To establish MP contamination baselines in the marine environment, marine biota species can be selected as monitoring matrices to track plastic pollution in the environment. The aim of this work was to evaluate the feasibility of biomonitoring MPs in fish gastrointestinal tract (GIT). A selection of suitable fish species was performed, based on species distribution, sampling effort, commercial value of species, sustainable development of fish populations, migration behaviour, and scientific evidence for occurrence of MPs in the fish GIT. Sampling and MP extraction protocols were developed and validated on fish GIT samples acquired in the Southern North Sea. The fish species selection protocol enabled the selection of ubiquitous distributed and non-endangered fish species relevant for MP monitoring in the North Sea. The fish GIT sampling protocol considered background contamination measures and sampling fillet as procedural blanks. Advantages and disadvantages of onboard dissection were discussed. The MPs extraction protocol was based on matrix digestion, density separation, and Nile red staining of particles followed by fluorescent microscopy observation. The confirmation of MPs identification and the analysis of the polymer composition was done using micro-Fourier transform infrared (μFTIR) spectroscopy. The MP analysis indicated a low number of MPs in the fish GIT. The mean number of particles per single fish GIT was 0.48 ± 0.81 (Nile red staining observations) to 0.26 ± 0.64 (corrected for background contamination). A power analysis (sampling effort) indicated that to detect significant differences, in a balanced-ANOVA type of analysis, between species and/or sampling areas, the sample size would require a minimum of 109 up to 370 individual fish. The feasibility of MP biomonitoring in fish GIT was assessed by a SWOT-analysis, which indicated that fish GIT is a suitable matrix for biomonitoring of MPs, but that the large number of samples needed to identify significant differences can be a major drawback. A potential implementation strategy for MP biomonitoring within Europe was suggested.

2021 ◽  
Vol 12 ◽  
Shuya Liu ◽  
Qing Xu ◽  
Kuiyan Liu ◽  
Yongfang Zhao ◽  
Nansheng Chen

Skeletonema species are cosmopolitan coastal diatoms that exhibit important roles in ecological system. The chloroplast genomes (cpDNAs) have been proven to be important in the study of molecular evolution and genetic diversity. However, cpDNA of only a single Skeletonema species (S. pseudocostatum) has been constructed, hindering in-depth investigation on Skeletonema species. In this study, complete cpDNAs of five Skeletonema species were constructed with cpDNAs of four species S. marinoi, S. tropicum, S. costatum, and S. grevillea constructed for the first time. These cpDNAs had similar sizes and same numbers of genes. These cpDNAs were highly syntenic with no substantial expansions, contractions, or inversions. Interestingly, two copies of petF, which encodes ferredoxin with critical role in iron dependency, were found in all five Skeletonema species, with one copy in the cpDNA and another copy in the nuclear genome of each species. Selection analysis revealed that all PCGs of cpDNAs were undergoing purifying selection. Despite the high conservation of these cpDNAs, nine genomic regions with high sequence divergence were identified, which illustrated substantial variations that could be used as markers for phylogenetic inference and for tracking Skeletonema species in the field. Additionally, the numbers of simple sequence repeats varied among different cpDNAs, which were useful for detecting genetic polymorphisms. The divergence times estimated using PCGs of cpDNAs revealed that most of these species were established within ∼33 Mya, consistent with that estimated using mtDNAs. Overall, the current study deepened our understanding about the molecular evolution of Skeletonema cpDNAs.

2021 ◽  
Vol 2 (4) ◽  
pp. 664-676
Kimberley C. Carter ◽  
Isabel A. T. Keane ◽  
Lisa M. Clifforde ◽  
Lewis J. Rowden ◽  
Léa Fieschi-Méric ◽  

Visitors to zoos can have positive, neutral, or negative relationships with zoo animals. This makes human–animal interactions (HAIs) an essential component of welfare and an important consideration in species selection for zoo exhibits and in enclosure designs. We measured the effect of visitors on reptiles by comparing open and closed periods during the lockdowns in response to the COVID-19 pandemic in the UK in a low-resolution dataset for thirteen species of reptiles and a high-resolution dataset focussing on just one of these. Scan sampling on thirteen reptile species (two chelonians and eleven squamates) showed species-specific differences in response to the presence/absence of visitors, with most taxa being only weakly affected. High-resolution scan sampling via video footage of an off-show and on-show enclosure was carried out for tokay geckos (Gekko gecko) over the open and closed periods. In this part of the study, tokay geckos were significantly more visible during zoo closure than when visitors were present on-exhibit, but there was no change in off-show animals, indicating the effect of visitors as opposed to other factors, such as seasonality, which applied equally to both on- and off-show animals. The high-resolution study showed that a significant effect was present for tokay geckos, even though the low-resolution suggested that they were more weakly affected than other taxa. Our results indicate that, for cryptic species such as this, more intensive sampling may be required to properly understand visitor effects. Our data do not allow the interpretation of effects on welfare but show that such assessments require a species-specific approach.

Aruna M. Rajapara ◽  
Mamta B. Shah

In medicinal plant field ethnopharmacological knowledge aggrandizes legibility for prioritizing species selection for future research opportunities. Many plant species representing the genus Onosma have been documented to be important in communities world-wide as evidenced by the numerous records on traditional medicinal and ethno-botanical information. Various species of the genus are used in the traditional medicinal systems in Europe and Asian countries especially in India, China, Turky and Pakistan. The literature on the species distribution and their characterization was compiled from different regional floras, regional revisions and databases. The information related to traditional uses, pharmacological activities and phytochemistry was systematically collected from the scientific databases including reference books, SciFinder, Scopus, PubMed and Google Scholar. Absence of comprehensive literature review on genus Onosma species led to design present study and dig the recorded documents to comparatively gauge magnitude of studies on each of the Onosma species through an exhaustive bibliographic evaluation of scientifically studied species of genus Onosma that are also taxonomically identified and are valued as traditional medicinal remedy for diseases in their countries of origin. The study hinted about lack of scientific literature on most of the species. A comprehensive bibliographic review on the geographical distribution, identification, traditional uses, phytochemistry, pharmacology and toxicology of the genus Onosma is attempted here to give insights into promising future drug discovery strategies. KEYWORDS: Onosma, Distribution, Traditional uses, Phyto-Pharmacology

2021 ◽  
Vol 10 (1) ◽  
Juliana G. de S. Magalhães ◽  
Mariano M. Amoroso ◽  
Bruce C. Larson

Abstract Background Projections of climate change impacts upon forests are likely inaccurate if based on the premise that only climate controls tree growth. Species interactions control growth, but most research has ignored these effects on how trees respond to climate change. Climate change is inducing natural species selection. However, this selection does not occur at the community level. Species selection starts with competition amongst individual trees. Competition is an individual-to-individual antagonistic interaction that, if severe, can constrain the presence of trees within a particular environment. Thus, climate change impacts individual tree selection within forests. Projecting climate change impacts on forests should account for the effects of climate on tree growth and the effects of competition. The inclusion of competition can increase the predictive power of simulations. Methods We propose a protocol to systematically map the available literature on climate change impacts on forests and produce a comprehensive list of methods applied to measure competition and model the competition effects on tree growth responses to climate change. This systematic map is not limited to any country or continent or specific tree species or forest type. The scope of the search focuses on time (when the evidence was published), location (geographic location of the evidence) and research design (competition indices and modelling methods). We will evaluate articles at three levels: title, abstract and full text. We will conduct a full-text assessment on all articles that pass a screening at the title and abstract stages. We will report the extracted evidence in a narrative synthesis to summarize the evidence’s trends and report knowledge gaps.

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