scholarly journals Occurrence Patterns, Photoperiod and Dispersion Ability of the Non-Marine Ostracoda (Crustacea) in Shallow Waters

2020 ◽  
Vol 21 (02) ◽  
pp. 73-85
Author(s):  
Okan Külköylüoğlu ◽  
Mehmet Yavuzatmaca ◽  
Derya Akdemir
Keyword(s):  
Habitat Preferences ◽  
Sampling Time ◽  
Shallow Waters ◽  
Species Occurrence ◽  
Natural Habitats ◽  
Effective Factor ◽  
Species Pairs ◽  
Occurrence Pattern ◽  
Species Specific ◽  
Occurrence Patterns

Patterns of species occurrence, dispersion ability, habitat preferences and sampling time can be important factors on the species composition. To understand effective roles of these factors on non-marine ostracods, samples were collected from 98 different shallow aquatic bodies from Osmaniye and Kilis provinces in Turkey. Total of 16 and 12 species were identified from the two provinces, respectively. All species are reported new for these provinces. Three species (Heterocypris incongruens, Ilyocypris inermis, I. bradyi) demonstrated the most frequent occurrences and abundances in up to seven different habitats. Species diversity and abundance were at least two times higher in natural habitats (streams, creeks) than artificial habitats (reservoirs, troughs). Numbers of species with and without swimming setae on the second antenna was not significantly different between lentic and lotic habitats. A positive co-occurrence pattern was found between Neglecandona neglecta and I. inermis while the rest of the species pairs exhibited random co-occurrences to each other. Canonical Correspondence Analysis showed 80.8% of correlation between species and environmental variables when water temperature was the major effective factor (P<0.05) on species occurrence. Sampling time did not make difference on the numbers of species between morning (06:30-11:58 a.m.) and after noon (12:05-19:52 p.m.). Results suggest that species occurrence seems to be related to species-specific characteristics in its n-dimensional niche where species deals with several other factors.

scholarly journals Herpetofauna of the Reserva Extrativista do Rio Gregório, Juruá Basin, southwest Amazonia, Brazil

Check List ◽  
2012 ◽  
Vol 8 (3) ◽  
pp. 360 ◽  
Author(s):  
Davi Lima Pantoja ◽  
Rafael De Fraga
Keyword(s):  
Species Richness ◽  
Habitat Preferences ◽  
Natural Populations ◽  
Sampling Time ◽  
Pitfall Traps ◽  
Vulnerable Species ◽  
Natural Habitats ◽  
High Species Richness ◽  
Negative Impacts ◽  
Floodplain Habitats

We present a checklist for reptiles and amphibians of the Reserva Extrativista do Rio Gregório, at the upper Juruá River basin, in the southwest Brazilian Amazonia. Using time-constrained searches, pitfall traps, vocalization, and accidental sightings, we recorded 84 species: 46 amphibians and 38 reptiles. Although analyses suggest still higher diversity, considering the short sampling time, relatively high species richness was documented, which reveals the relevance of this region for conservation. Species richness did not differ between upland and floodplain habitats. Species compositions were significant different between these habitat categories for amphibians and snakes, but not for lizards, suggesting some habitat preferences. Additionally, we found threatened and vulnerable species. We did not assess impacts of human activities on natural populations in RESEX do Rio Gregório, but since resident people have directly used natural resources (e.g. consuming turtles and modifying natural habitats), we recommend monitoring biodiversity to avoid negative impacts.

Distribution and habitat preference of protected reindeer lichen species (Cladonia arbuscula, C. mitis and C. rangiferina) in the Balaton Uplands (Hungary)

2021 ◽  
Vol 53 (3) ◽  
pp. 271-282
Author(s):  
Mónika Sinigla ◽  
Erzsébet Szurdoki ◽  
László Lőkös ◽  
Dénes Bartha ◽  
István Galambos ◽  
...  
Keyword(s):  
Vascular Plants ◽  
Management Practices ◽  
Soil Depth ◽  
Habitat Preferences ◽  
Habitat Type ◽  
Canopy Cover ◽  
Lichen Species ◽  
Oak Forests ◽  
Natural Habitats ◽  
Cladonia Rangiferina

AbstractThe maintenance of protected lichen species and their biodiversity in general depends on good management practices based on their distribution and habitat preferences. To date, 10 of the 17 protected lichen species of Hungary have been recorded in the Bakony Mts including the Balaton Uplands region. Habitat preferences of three protected Cladonia species (C. arbuscula, C. mitis and C. rangiferina) growing on underlying rocks of red sandstone, basalt, Pannonian sandstone and gravel were investigated by detailed sampling. We recorded aspect, underlying rock type, soil depth, pH and CaCO3 content, habitat type (as defined by the General National Habitat Classification System Á-NÉR), all species of lichen, bryophyte and vascular plants as well as percentage cover of exposed rock, total bryophytes, lichens, vascular plants and canopy, degree of disturbance and animal impacts. Sporadic populations of these species mostly exist at the top of hills and mountains in open acidofrequent oak forests, but they may occur in other habitats, such as closed acidofrequent oak forests, slope steppes on stony soils, siliceous open rocky grasslands, open sand steppes, wet and mesic pioneer scrub and dry Calluna heaths. Cladonia rangiferina was found to grow beneath higher canopy cover than either C. arbuscula or C. mitis in the Balaton Uplands. Furthermore, there were significant differences in canopy cover between occupied and unoccupied quadrats in the case of all three species. Cladonia rangiferina is a good indicator species of natural habitats in Hungary due to its restricted distribution and low ecological tolerance. These results may lead to the adoption of effective conservation methods (e.g. game exclusion, artificial dispersal) in the future.

scholarly journals Species-Specific Segregation of Gender-Associated Mitochondrial DNA Types in an Area Where Two Mussel Species (Mytilus edulis and M. trossulus) Hybridize

Genetics ◽  
1996 ◽  
Vol 143 (3) ◽  
pp. 1359-1367 ◽  
Author(s):  
Carlos Saavedra ◽  
Donald T Stewart ◽  
Rebecca R Stanwood ◽  
Eleftherios Zouros
Keyword(s):  
Mytilus Edulis ◽  
The Other ◽  
Allozyme Analysis ◽  
Mussel Species ◽  
Species Origin ◽  
Species Pairs ◽  
Nuclear Background ◽  
Species Specific ◽  
Dna Types ◽  
Fertile Hybrids

Abstract In each of the mussel species Mytilus edulis and M. trossulus there exist two types of mtDNA, the F type transmitted through females and the M type transmitted through males. Because the two species produce fertile hybrids in nature, F and M types of one may introgress into the other. We present the results from a survey of a population in which extensive hybridization occurs between these two species. Among specimens classified as “pure” M. edulis or “pure” M. trossulus on the basis of allozyme analysis, we observed no animal that carried the F or the M mitotype of the other species. In most animals of mixed nuclear background, an individual's mtDNA came from the species that contributed the majority of the individual's nuclear genes. Most importantly, the two mtDNA types in post-F1 male hybrids were of the same species origin. We interpret this to mean that there are intrinsic barriers to the exchange of mtDNA between these two species. Because such barriers were not noted in other hybridizing species pairs (many being even less interfertile than M. edulis and M. trossulus), their presence in Mytilus could be another feature of the unusual mtDNA system in this genus.

scholarly journals The importance of motivation, weapons, and foul odors in driving encounter competition in carnivores

2020 ◽  
Author(s):  
ML Allen ◽  
CC Wilmers ◽  
LM Elbroch ◽  
JM Golla ◽  
Heiko Wittmer
Keyword(s):  
Interference Competition ◽  
Current Theory ◽  
Lynx Rufus ◽  
Natural Environments ◽  
Ecological Communities ◽  
Competitive Advantages ◽  
Ecological Society ◽  
Strategic Behaviors ◽  
Species Specific ◽  
Occurrence Patterns

© 2016 by the Ecological Society of America. Encounter competition is interference competition in which animals directly contend for resources. Ecological theory predicts the trait that determines the resource holding potential (RHP), and hence the winner of encounter competition, is most often body size or mass. The difficulties of observing encounter competition in complex organisms in natural environments, however, has limited opportunities to test this theory across diverse species. We studied the outcome of encounter competition contests among mesocarnivores at deer carcasses in California to determine the most important variables for winning these contests. We found some support for current theory in that body mass is important in determining the winner of encounter competition, but we found that other factors including hunger and species-specific traits were also important. In particular, our top models were "strength and hunger" and "size and hunger," with models emphasizing the complexity of variables influencing outcomes of encounter competition. In addition, our wins above predicted (WAP) statistic suggests that an important aspect that determines the winner of encounter competition is species-specific advantages that increase their RHP, as bobcats (Lynx rufus) and spotted skunks (Spilogale gracilis) won more often than predicted based on mass. In complex organisms, such as mesocarnivores, species-specific adaptations, including strategic behaviors, aggressiveness, and weapons, contribute to competitive advantages and may allow certain species to take control or defend resources better than others. Our results help explain how interspecific competition shapes the occurrence patterns of species in ecological communities.

scholarly journals A Social Recommendation Based on Metric Learning and Users’ Co-Occurrence Pattern

Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2158
Author(s):  
Xin Zhang ◽  
Jiwei Qin ◽  
Jiong Zheng
Keyword(s):  
Matrix Factorization ◽  
Triangle Inequality ◽  
Metric Learning ◽  
Social Recommendation ◽  
Rating Data ◽  
Fine Grained ◽  
Information Metric ◽  
Occurrence Pattern ◽  
Public Datasets ◽  
Occurrence Patterns

For personalized recommender systems, matrix factorization and its variants have become mainstream in collaborative filtering. However, the dot product in matrix factorization does not satisfy the triangle inequality and therefore fails to capture fine-grained information. Metric learning-based models have been shown to be better at capturing fine-grained information than matrix factorization. Nevertheless, most of these models only focus on rating data and social information, which are not sufficient for dealing with the challenges of data sparsity. In this paper, we propose a metric learning-based social recommendation model called SRMC. SRMC exploits users’ co-occurrence patterns to discover their potentially similar or dissimilar users with symmetric relationships and change their relative positions to achieve better recommendations. Experiments on three public datasets show that our model is more effective than the compared models.

scholarly journals Bioacoustic characterization of mating calls of a freshwater fish (Prochilodus magdalenae) for passive acoustic monitoring

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Sebastián Muñoz-Duque ◽  
Silvia López-Casas ◽  
Héctor Rivera-Gutiérrez ◽  
Luz Jiménez-Segura
Keyword(s):  
Pulse Rate ◽  
Peak Frequency ◽  
Acoustic Monitoring ◽  
Passive Acoustic Monitoring ◽  
Natural Habitats ◽  
Train Duration ◽  
Acoustic Characterization ◽  
Species Specific ◽  
Passive Acoustic

Fish produce sounds that are usually species-specific and associated with particular behaviors and contexts. Acoustic characterization enables the use of sounds as natural acoustic labels for species identification. Males of Prochilodus magdalenae produce mating sounds. We characterized  these sounds and tested their use in natural habitats, to use passive acoustic monitoring for spawning ground identification. We identified two types of acoustic signals: simple pulses and pulse trains. Simple pulses were 13.7 ms long, with peak frequency of 365 Hz, whereas pulse train were 2.3 s long, had peak frequency of 399 Hz, 48.6 pulses and its pulses lasted 12.2 ms, with interpulse interval of 49.0 ms long and 22.3 Hz pulse rate. We did not detect spawning in  absence of male calls nor differences in male sounds at different female densities. We found differences in train duration, pulse rate, and pulse duration in trains, according to the fish's source sites, but these sites were not well discriminated based on bioacoustical variables. In rivers, we located two P. magdalenae spawning grounds and recognized calls from another fish species (Megaleporinus muyscorum). We did not find a significant relationship between fish size and call peak frequency for P. magdalenae.

scholarly journals Bees use anthropogenic habitats despite strong natural habitat preferences

2018 ◽  
Author(s):  
Miguel Á. Collado ◽  
Daniel Sol ◽  
Ignasi Bartomeus
Keyword(s):  
Habitat Loss ◽  
Natural Habitat ◽  
Habitat Preferences ◽  
Abundant Species ◽  
Comprehensive Analysis ◽  
Natural Habitats ◽  
Large Dataset ◽  
Anthropogenic Habitats ◽  
Bee Diversity ◽  
Northeast Usa

ABSTRACTHabitat loss and alteration is widely considered one of the main drivers of the current loss of pollinator diversity. Unfortunately, we still lack a comprehensive analysis of habitat importance, use and preference for major groups of pollinators. Here, we address this gap analysing a large dataset of 15,762 bee specimens (more than 400 species) across northeast USA. We found that natural habitats sustain the highest bee diversity, with many species strongly depending on such habitats. By characterizing habitat use and preference for the 45 most abundant species, we also show that many bee species can use human-altered habitats despite exhibiting strong and clear preferences for forested habitats. However, only a few species appear to do well when the habitat has been drastically modified. We conclude that although altered environments may harbor a substantial number of species, preserving natural areas is still essential to guarantee the conservation of bee biodiversity.

scholarly journals The Role of Plasticity and Adaptation in the Incipient Speciation of a Fire Salamander Population

Genes ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 875
Author(s):  
Joana Sabino-Pinto ◽  
Daniel J. Goedbloed ◽  
Eugenia Sanchez ◽  
Till Czypionka ◽  
Arne W. Nolte ◽  
...  
Keyword(s):  
Gene Expression ◽  
Phenotypic Plasticity ◽  
Local Adaptation ◽  
Habitat Preferences ◽  
Genetic Change ◽  
Incipient Speciation ◽  
Expression Of Genes ◽  
Species Specific ◽  
Reciprocal Transfer ◽  
High Degree

Phenotypic plasticity and local adaptation via genetic change are two major mechanisms of response to dynamic environmental conditions. These mechanisms are not mutually exclusive, since genetic change can establish similar phenotypes to plasticity. This connection between both mechanisms raises the question of how much of the variation observed between species or populations is plastic and how much of it is genetic. In this study, we used a structured population of fire salamanders (Salamandra salamandra), in which two subpopulations differ in terms of physiology, genetics, mate-, and habitat preferences. Our goal was to identify candidate genes for differential habitat adaptation in this system, and to explore the degree of plasticity compared to local adaptation. We therefore performed a reciprocal transfer experiment of stream- and pond-originated salamander larvae and analyzed changes in morphology and transcriptomic profile (using species-specific microarrays). We observed that stream- and pond-originated individuals diverge in morphology and gene expression. For instance, pond-originated larvae have larger gills, likely to cope with oxygen-poor ponds. When transferred to streams, pond-originated larvae showed a high degree of plasticity, resembling the morphology and gene expression of stream-originated larvae (reversion); however the same was not found for stream-originated larvae when transferred to ponds, where the expression of genes related to reduction-oxidation processes was increased, possibly to cope with environmental stress. The lack of symmetrical responses between transplanted animals highlights the fact that the adaptations are not fully plastic and that some level of local adaptation has already occurred in this population. This study illuminates the process by which phenotypic plasticity allows local adaptation to new environments and its potential role in the pathway of incipient speciation.

scholarly journals Historical changes in land use influence current habitat preferences of large herbivores

2019 ◽  
Vol 34 (10) ◽  
pp. 2251-2259 ◽  
Author(s):  
Kajetan Perzanowski ◽  
Maciej Januszczak ◽  
Rafał Łopucki
Keyword(s):  
Land Use ◽  
Spatial Distribution ◽  
Habitat Preferences ◽  
Field Research ◽  
Study Data ◽  
European Bison ◽  
Large Herbivore ◽  
Large Herbivores ◽  
Historical Changes ◽  
Effective Factor

Abstract Context Predicting habitat use patterns is a key issue in the management of large herbivore populations. Particularly, indicators providing a model of the spatial distribution of a population in a simple way, without the necessity of laborious field research, are still being sought. Analysis of historical landscape changes can be one of such predictive tools. Objectives We tested the hypothesis that historical changes in land use can be used as an effective factor enabling prediction of spatial distribution. As a case study, data on habitat preferences of European bison Bison bonasus (wisents) were used. Methods Spatial distribution of 17302 records of the presence of wisents, collected over the period of 10 years, was compared using contemporary and historical habitat maps for the Bieszczady Mts. (Poland). The area of approx. 87 thousand ha was selected, where the density of human population decreased over four times, and the percentage of forests increased from over 30% to almost 80% due to land abandonment. Results Wisents were recorded significantly more frequently in parts of the forest that in the past were used for agriculture. We found that identification of parts of the forest overgrowing former cultivated fields makes it possible to predict the spatial distribution of wisent herds with very high probability. Conclusions Information on historical changes in land use can be used as a simple and effective factor enabling prediction of habitat selection by wisents. Such an approach can potentially be useful for similar assessments of other large wild herbivores.

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