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1.
Life (Basel) ; 13(12)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38137877

RESUMO

Microtus thomasi (Rodentia: Arvicolinae), a fossorial vole endemic to the SW Balkans, uses a variety of substrates but its underground behavior remains poorly understood. This study examines the architecture and utilization of M. thomasi burrow systems in NW Peloponnese, Greece. In particular, eight burrow systems were meticulously excavated and studied, with comprehensive measurements taken of key characteristics, including length, depth, soil mounds, and surface openings. Key coordinates were recorded using a differential GPS device for detailed mapping and fractal dimension analysis using the box-counting method was employed to assess burrow system complexity. Soil samples were analyzed for particle size and chemical composition, and vegetation types at each site were identified. We did not find statistically significant correlations between size and complexity of the burrow systems and soil composition, altitude, or specific soil components. On the other hand, we did observe statistically significant differences in tunnel diameter between two burrow systems and in tunnel depth between more. Moreover, our study showed that more than one same-sex individual can occupy a single burrow system and not just an adult male-female pair, that was previously recorded, indicating the need for further study of the social behavior of this vole species. This study provides valuable insights into the underground behavior of M. thomasi by providing information on the features of its burrow systems, thus contributing to our understanding of its biology.

2.
Zootaxa ; 5239(4): 451-476, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-37045087

RESUMO

The Aciculidae is a family of terrestrial operculate snails with a western Palaearctic distribution. Historically three Acicula species were reported from the Caucasus Mountains, which represents the eastern edge of the family's distribution: A. limbata, A. moussoni and A. parcelineata, all from a few localities. We examined extensive material from the entire range of the Caucasus Mountains by means of classic morphology-based taxonomy and geometric morphometries. We arrived at the following conclusions: (1) At least three species inhabit the Caucasus Mountains, two of which are problematic taxonomically and regarding their nomenclature. (2) The two syntypes of A. moussoni have been lost, and both lectotype designations by the former authors were invalid. Therefore, we designate a neotype for A. moussoni. (3) Acicula limbata was described from Lower Miocene deposits of the Czech Republic. Although the fossil Central European and extant Caucasian shells differ only slightly from one another, it is highly unlikely that they would belong to the same species. Therefore, we suggest using A. limbata only for the Czech fossil species and A. moussoni for the Caucasian extant species. (4) In multiple samples, the generally smaller Acicula parcelineata was found syntopic with the generally larger A. moussoni. Therefore, the two are possibly distinct species. However, it is very difficult to distinguish, and the problem of A. moussoni and A. parcelineata needs further attention. (5) A species with a bullet (or torpedo)-shaped shell and an opisthocline apertural profile from the northern Caucasus region has been treated as A. moussoni by previous authors, but it is distinct from the other two Acicula species by consistent conchological characters and was also found with them in syntopy, and is described here as Acicula telum Páll-Gergely, n. sp.


Assuntos
Gastrópodes , Animais , Caramujos , Fósseis
3.
Proc Biol Sci ; 288(1958): 20211603, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34493076

RESUMO

Flying over the open sea is energetically costly for terrestrial birds. Despite this, over-water journeys of many birds, sometimes hundreds of kilometres long, are uncovered by bio-logging technology. To understand how these birds afford their flights over the open sea, we investigated the role of atmospheric conditions, specifically wind and uplift, in subsidizing over-water flight at a global scale. We first established that ΔT, the temperature difference between sea surface and air, is a meaningful proxy for uplift over water. Using this proxy, we showed that the spatio-temporal patterns of sea-crossing in terrestrial migratory birds are associated with favourable uplift conditions. We then analysed route selection over the open sea for five facultative soaring species, representative of all major migratory flyways. The birds maximized wind support when selecting their sea-crossing routes and selected greater uplift when suitable wind support was available. They also preferred routes with low long-term uncertainty in wind conditions. Our findings suggest that, in addition to wind, uplift may play a key role in the energy seascape for bird migration that in turn determines strategies and associated costs for birds crossing ecological barriers such as the open sea.


Assuntos
Voo Animal , Vento , Migração Animal , Animais , Aves , Água
4.
J Environ Manage ; 300: 113799, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34560464

RESUMO

Given that the social and economic sustainability of rural areas is highly based on the protection of natural resources, biodiversity and human health, simple-operated and cost-effective wastewater treatment systems, like artificial constructed wetlands (CWs), are widely proposed for minimizing the environmental and human impact of both water and soil pollution. Considering that the optimization of wastewater treatment processes is vital for the reduction of effluents toxic potential, there is imperative need to establish appropriate management strategies for ensuring CW performance and operational efficiency. To this end, the present study aimed to assess the operational efficiency of a horizontal free water surface CW (HFWS-CW) located in a world heritage area of Western Greece, via a twelve-month duration Toxicity Identification Evaluation (TIE)-like approach, including both chemical and biological tracking tools. Conventional chemical tracking, by means of pH, conductivity, total COD, and nitrogen-derived components, like nitrates and ammonia-nitrogen, were monthly recorded in both influents and effluents to monitor whether water quality standards are maintained, and to assess potent CW operational deficiencies occurring over time. In parallel, Whole Effluent Toxicity (WET) bioassays were thoroughly applied, using freshwater algae and higher plant species (producers), crustaceans and rotifers (consumers), as well as human lymphocytes (in terms of Cytokinesis Block Micronucleus assay) to evaluate the acute and short-term toxic and hazardous potential of both influents and effluents. The integrated analysis of abiotic (physicochemical parameters) and biotic (toxic endpoints) parameters, as well as the existence of "cause-effect" interrelations among them, revealed that CW operational deficiencies, mainly based on poorly removal rates, could undermine the risk posed by treated sewage. Those findings reinforce the usage of WET testing, thus giving rise to the importance of applying appropriate water management strategies and optimization actions, like oxygen enrichment of surface and bottom of HFWS-CW basins, expansion of the available land, the enhancement of bed depth and seasonal harvesting of plants, for ensuring sewage quality, in favor of water resources protection and sustainable growth in rural areas.


Assuntos
Purificação da Água , Áreas Alagadas , Humanos , Saneamento , Eliminação de Resíduos Líquidos , Águas Residuárias
5.
Sci Total Environ ; 711: 135101, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000341

RESUMO

In the present study we investigated seasonal and intrinsic variability of neurotoxic and cyto-genotoxic biomarkers in blood plasma and erythrocytes of free-living Eleonoras' falcons, captured during the pre-breeding (May of 2017 and 2018) and breeding period (September of 2017) on the Antikythira Island (Greece). Specifically, blood samples of captured birds were prepared for the determination of cholinesterase (ChEs, i.e. acetylcholinesterase/AChE and butyrylcholinesterase/ BChE) activity, as well as the formation of nuclear (i.e. the formation of micronuclei into the cells/MN, binucleated cells/BN and others), and cellular/cytoplasmic (i.e. echinocytes/EC, acanthocytes/AC and notched cells/NC) abnormalities in blood plasma and erythrocytes, respectively. Our results indicated that birds sampled in late May had higher ChE and BChE activity levels, as well as higher frequency of total nuclear abnormalities. The latter were also higher in second calendar year (2cy) birds. Cellular/cytoplasmic abnormalities were less frequent in falcons having better body condition, sampled in late May, as well as in light-morph falcons. The observed ChEs activities, as well as nuclear and cellular/cytoplasmic abnormalities revealed that Eleonora's falcons are likely to be exposed to chemical agents with neurotoxic and cyto-genotoxic potential year round, while different aspects of their biology and ecology, such as their reproductive and nutritional status, could mediate their levels. Although we encourage more sampling campaigns to verify the identified seasonal and intrinsic sources of variation in biomarkers tested, the current study enriches the existing knowledge about their usefulness in the environmental monitoring and risk assessment of migratory birds, like Eleonoras' falcon.


Assuntos
Falconiformes , Animais , Biomarcadores , Dano ao DNA , Grécia , Estações do Ano
6.
J Biol Res (Thessalon) ; 26: 6, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31489280

RESUMO

Herein we present the recently founded Hellenic Evolutionary Society (HEVOS) that has been recently instituted to promote evolution and scientific thinking among the Greek-speaking public. HEVOS is a timely initiative, given the low levels of acceptance of evolution by Greek society and the almost complete lack of evolution teaching in primary and secondary education in Greece. Herein, the main aims of the Society are presented.

7.
Sci Rep ; 7(1): 8798, 2017 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-28821735

RESUMO

Conservation of migratory species faces the challenge of understanding the ecological requirements of individuals living in two geographically separated regions. In some cases, the entire population of widely distributed species congregates at relatively small wintering areas and hence, these areas become a priority for the species' conservation. Satellite telemetry allows fine tracking of animal movements and distribution in those less known, often remote areas. Through integrating satellite and GPS data from five separated populations comprising most of the breeding range, we created a wide habitat suitability model for the Eleonora's falcon on its wintering grounds in Madagascar. On this basis, we further investigated, for the first time, the impact of climate change on the future suitability of the species' wintering areas. Eleonora's falcons are mainly distributed in the north and along the east of Madagascar, exhibiting strong site fidelity over years. The current species' distribution pattern is associated with climatic factors, which are likely related to food availability. The extent of suitable areas for Eleonora's falcon is expected to increase in the future. The integration of habitat use information and climatic projections may provide insights on the consequences of global environmental changes for the long-term persistence of migratory species populations.


Assuntos
Migração Animal , Aves Predatórias , Estações do Ano , Animais , Ecossistema , Geografia , Madagáscar
8.
Curr Zool ; 63(2): 139-149, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29491971

RESUMO

Every spring a huge number of passerines cross the Sahara Desert and the Mediterranean Sea on their way to their breeding grounds. Stopover sites after such extended barriers where birds can rest, refuel, and find shelter from adverse weather, are of crucial importance for the outcome of their migration. Stopover habitat selection used by migrating birds depends on landscape context, habitat patch characteristics, as well as on the particular energetic conditions and needs of individual birds, but it is still poorly investigated. We focused on a long-distance migrating passerine, the woodchat shrike, in order to investigate for the first time the species' habitat selection at a spring stopover site (island of Antikythira, Greece) after the crossing of the Sahara Desert and Mediterranean Sea. We implemented radio-tracking, color-ringing, and visual behavioral observations to collect data on microhabitat use. Generalized Linear Mixed Models were developed to identify the species' most preferred microhabitat during its stopover on this low human disturbed island. We found that high maquis vegetation surrounded by low vegetation was chosen as perches for hunting. Moreover, high maquis vegetation appeared to facilitate hunting attempts toward the ground, the most frequently observed foraging strategy. Finally, we discuss our findings in the context of conservation practices for the woodchat shrike and their stopover sites on Mediterranean islands.

9.
J Hazard Mater ; 321: 537-546, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-27676080

RESUMO

The present study evaluates a battery of marine species-based bioassays against chemically characterized municipal wastewater samples (raw and WWTP treated). We estimated Dunaliella tertiolecta growth rate inhibition (24-96h IC50 values), Artemia franciscana immobilization (24h LC50 values), mussel hemocytes viability and lipid peroxidation enhancement (in terms of neutral red retention assay/NRRT and malondialdehyde/MDA content, respectively) in influent- and WWTP effluent-treated species. We found algal growth arrest and stimulation respectively, almost similar 24hLC50 values in Artemia sp., and significantly higher adverse effects (in terms of NRRT and MDA levels) in influent-treated mussel hemocytes. Furthermore, the estimation of hatchability, yolk-sac larvae mortality (24-120hLC50) and spinal deformities (SD) in sea bream Sparus aurata showed slight variations over time, with the lowest LC50 and SD50 (representing spinal deformities at 50% of yolk-sac larvae) values to be observed in influent-treated larvae at 120h. Data interpretation (both chemical and biological) revealed that toxic endpoints, such as NRRT50, 96hIC50Dun, 120hLC50Sparus and 120hSD50Sparus, significantly related to WWTP removal efficiency and further mediated by the presence of dominant compounds, such as As and Cr, could be used for identifying main components of toxicity in wastewaters.


Assuntos
Organismos Aquáticos/metabolismo , Bioensaio/métodos , Águas Residuárias/química , Águas Residuárias/toxicidade , Animais , Artemia/metabolismo , Bivalves/metabolismo , Clorófitas/metabolismo , Hemócitos/efeitos dos fármacos , Larva/efeitos dos fármacos , Dose Letal Mediana , Metabolismo dos Lipídeos/efeitos dos fármacos , Dourada , Eliminação de Resíduos Líquidos , Saco Vitelino
10.
J Therm Biol ; 63: 24-30, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28010812

RESUMO

Amphibian populations have been declining globally for the last several decades, and climate change is often regarded as one of the most important factors driving these declines. Amphibians are particularly sensitive to climatic changes due to their physiological, ecological and behavioral characteristics. Here we performed a laboratory experiment to investigate how temperature affects ovipositing females, eggs and hatchlings in two syntopic populations of alpine newts, Ichthyosaura alpestris, and smooth newts, Lissotriton vulgaris. Female newts were assigned to two different oviposition temperatures (11°C and 14°C) for the duration of their oviposition period. Deposited eggs were equally divided and assigned to three different incubation temperatures (11°C, 14°C and 17°C). We hypothesized that oviposition will be affected by temperature, that the combination of different oviposition and incubation temperatures may have an effect on embryonic and hatchling traits (embryonic mortality, days to hatch and hatchling length), and that these effects might differ between the two newt species. Temperature affected the number of deposited eggs in smooth newts, but not in alpine newts. Larval hatching success was not affected by oviposition or incubation temperature. Temperature effects on hatching time and hatchling length differed between the two species. These results suggest that temperature changes may have disparate effects on amphibian reproduction, even in syntopic taxa.


Assuntos
Aclimatação , Temperatura Baixa , Oviposição , Salamandridae/fisiologia , Animais , Temperatura Corporal , Feminino , Salamandridae/embriologia , Especificidade da Espécie , Zigoto/fisiologia
11.
Zookeys ; (640): 1-18, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28138282

RESUMO

A new to science valvatiform hydrobiid, Myrtoessa hyas Radea, gen. n. & sp. n., from southern Greece, is described and illustrated. The new genus is a tiny gastropod thriving in a stream and is differentiated from the other known European and circum-Mediterranean valvatiform hydrobiid genera by a unique combination of the male and female genitalia features i.e. penis long, flat, blunt, with wide wrinkled proximal part and narrow distal part with a sub-terminal eversible papilla on its left side, bursa copulatrix well-developed, pyriform, fully protruding from the posterior end of the albumen gland and two seminal receptacles respectively. The new monotypic and locally endemic genus is narrowly distributed and its single known population nearby a coastal bustling village is vulnerable to anthropogenic stressors.

12.
PLoS One ; 9(6): e100366, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24964101

RESUMO

Drilus beetle larvae (Coleoptera: Elateridae) are specialized predators of land snails. Here, we describe various aspects of the predator-prey interactions between multiple Drilus species attacking multiple Albinaria (Gastropoda: Clausiliidae) species in Greece. We observe that Drilus species may be facultative or obligate Albinaria-specialists. We map geographically varying predation rates in Crete, where on average 24% of empty shells carry fatal Drilus bore holes. We also provide first-hand observations and video-footage of prey entry and exit strategies of the Drilus larvae, and evaluate the potential mutual evolutionary impacts. We find limited evidence for an effect of shell features and snail behavioral traits on inter- and intra-specifically differing predation rates. We also find that Drilus predators adjust their predation behavior based on specific shell traits of the prey. In conclusion, we suggest that, with these baseline data, this interesting predator-prey system will be available for further, detailed more evolutionary ecology studies.


Assuntos
Besouros , Comportamento Predatório , Caramujos , Animais , Biodiversidade , Evolução Molecular , Grécia , Larva
13.
Mol Phylogenet Evol ; 62(2): 681-92, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22142739

RESUMO

The aim of this work was to infer the phylogeny of the Greek endemic land-snail genus Codringtonia Kobelt 1898, estimate the time frame of the radiation of the genus, and propose a biogeographic scenario that could explain the contemporary distribution of Codringtonia lineages. The study took place in the districts of Peloponnese, Central Greece and Epirus of mainland Greece. Sequence data originating from three mtDNA genes (COI, COII, and 16S rDNA) were used to infer the phylogeny of the eight nominal Codringtonia species. Furthermore, the radiation time-frame of extant Codringtonia species was estimated using a relaxed molecular clock analysis and mtDNA substitution rates of land snails. The phylogenetic analysis supported the existence of six Codringtonia lineages in Greece and indicated that one nominal species (Codringtonia neocrassa) might belong to a separate genus distantly related to Codringtonia. The time frame of differentiation of Codringtonia species was placed in the Late Miocene-Pleistocene epoch. The dispersal-vicariance analysis performed indicated that most probably Codringtonia exhibited a north-to-south spread with the ancestral area being that of central Greek mainland, accompanied with duplication (speciation) and vicariance events.


Assuntos
DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Especiação Genética , Filogenia , RNA Ribossômico 16S/genética , Caramujos/genética , Animais , Sequência de Bases , Teorema de Bayes , Biodiversidade , Evolução Biológica , Grécia , Funções Verossimilhança , Modelos Genéticos , Filogeografia , Análise de Sequência de DNA , Caramujos/classificação , Especificidade da Espécie
14.
Mol Phylogenet Evol ; 44(3): 1224-36, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17320418

RESUMO

Mitochondrial DNA sequences from 16S rRNA and ATPase8 genes were used to investigate phylogeographic patterns of the land snail Albinaria (Gastropoda: Clausiliidae) in the Aegean archipelago. Forty-two populations of Albinaria were analyzed, mainly A. turrita, A. caerulea and A. brevicollis, collected from 22 Aegean islands and certain surrounding regions. Maximum parsimony, maximum likelihood and Bayesian analyses on 16S rRNA and combined datasets produced trees that share significant similarity and reveal a phylogeny with distinct branches which are in general, but not full, agreement with current taxonomy. The Aegean taxa are not monophyletic as a whole, since A. turrita does not cluster with A. caerulea and A. brevicollis. The latter form a distinct monophyletic cluster, within which two groups are evident. These groups do not readily correspond to currently accepted morphospecies; one contains the populations that inhabit the central part of the archipelago plus some eastern islands, while the other contains populations whose geographic distribution is restricted to the southeastern part of the archipelago. The divergence between these two groups is attributed to vicariance events that primarily shape contemporary distributions. Although dispersal may also be present, certain small- and large-scale vicariance events can be traced; alternative phylogeographic hypotheses are discussed in view of the historical biogeography of the region.


Assuntos
Caramujos/classificação , Caramujos/genética , Animais , Sequência de Bases , Primers do DNA/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Evolução Molecular , Grécia , Funções Verossimilhança , Ilhas do Mediterrâneo , ATPases Mitocondriais Próton-Translocadoras/genética , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Fatores de Tempo
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