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At least 19 recordsLinked to original sources

PubMed2026

DNA Extraction Optimisation for Minute Land Snails of Vertigo Müller, 1773 (Gastropoda: Vertiginidae): A Comparative Evaluation of Six Methods, Including a Non-Destructive Shell-Preserving Protocol.

No systematic comparison of DNA extraction strategies exists for minute Vertiginidae (shell height < 3 mm), a group posing a dual analytical challenge: extremely low tissue input and co-purified PCR-inhibitory mucus. For legally protected species, an additional requirement to preserve the shell voucher further constrains available protocols. Using Vertigo antivertigo as the model species, we compared six approaches applied to specimens preserved in 96% ethanol (n = 10 per method): two HotSHOT alkaline-lysis protocols (destructive and non-destructive shell-preserving variants), a modified CTAB protocol supplemented with PVP-40 and DTT, and three commercial silica-column kits (GeneJET Genomic, DNeasy Blood & Tissue, QIAamp DNA Micro). DNA yields were quantified by QuantiFluor fluorometry, and PCR performance was subsequently assessed across four loci (COI barcode, COI mini-barcode, ITS1, ITS2). DNeasy Blood & Tissue produced the highest fluorometric concentrations; QIAamp DNA Micro and CTAB + PVP-40 gave intermediate values. The shell-preserving HotSHOT variant yielded lower concentrations but improved A260/230 ratios. BSA and trehalose supplementation increased PCR success in inhibition-prone HotSHOT extracts from 70% to 100%. ITS1 Sanger sequencing of three Vertigo species listed in Annex II of the EU Habitats Directive, all extracted with the shell-preserving protocol, confirmed species-level identification (99.8%-100% BLASTn identity; mean Phred Q > 51). The shell-preserving non-destructive HotSHOT protocol yields sequenceable DNA from protected Vertiginidae while retaining the morphological voucher, making it the preferred option for conservation-genetic monitoring. The practical decision framework documented here-integrating voucher preservation, amplification robustness and per-sample cost-has broad applicability to other minute terrestrial gastropods processed in large-scale biodiversity surveys.

Habitats Directive↗

PubMed2026

Beauty bias in butterfly research and conservation.

Conservation biases have been documented since the first emergence of the concept of biodiversity in the 1980s,1,2,3 showing a systematic disproportion in the allocation of research and conservation efforts among taxa.4,5,6,7,8,9,10,11 One factor underlying this disproportion, gaining prominence in recent literature, is species' perceived beauty, shaped by human visual preferences.12,13,14,15,16,17 Here, we integrate a large-scale survey of the perceived beauty of European butterflies yielding >21,000 survey completions from >100 countries into a time-explicit network linking species' beauty, public attention, research and conservation efforts, and the EU regulatory framework. We found that species beauty is consistently associated with public attention, research, and conservation efforts in a temporally structured pattern compatible with a cumulative beauty bias. Research effort and public attention concentrate on widespread and visually attractive species, whereas species included in the legal conservation framework, particularly the Convention on the Conservation of European Wildlife and Natural Habitats (hereafter, Bern Convention, BC, 1979)18 and the EU Habitats Directive (hereafter, HD, 1992)19 are disproportionately represented by visually appealing and historically protected taxa. Because these frameworks guide funding and management actions, early associations between species beauty and BC/HD inclusion have contributed to long-lasting institutional patterns in butterfly research and conservation. By contrast, European IUCN Red Lists20,21 do not overrepresent beautiful species and identify more inconspicuous taxa as threatened. This mismatch reveals a tension between scientific assessments of extinction risk and historically embedded conservation priorities. Our findings suggest that recognizing beauty bias is vital for aligning conservation with actual ecological urgency. VIDEO ABSTRACT.

Animals↗

PubMed1989

Ecology and affective behavior: selected results from a quantitative study among Efe foragers of northeast Zaire.

This paper reports selected results of a quantitative study of the affective behavior of the Efe, exchange-dependent hunter-gatherers of the Ituri forest in northeastern Zaire. Measures of the amount and kind of affective display were based on systematic, direct observation of the routine behavior of three Efe bands in residential settings (camps), using a new technique to characterize affect-laden behavior according to nonlinguistic information conveyed in the voice. Resulting data provide a direct measure of the affective milieu of a foraging people, providing an objective indicator of the subjective impact of social and ecological conditions, which are thought to affect quality of life. In this paper, measures of "camp mood" are used to explore the psychosocial impact of a 3-month period of acute food shortage that occurred in the Ituri Project study area in 1983. Contrary to expectation, rates of behaviors conveying pleasure did not exhibit significant change, whereas a 44% increase in expressions of displeasure and a 17% drop in use of complaint tones were observed during the period of hunger. This and other findings support the view that systematic, direct observation in natural habitats can increase our understanding, both of the functions of affective behavior, and of the affective dimension of quality of life.

Affect↗

PubMed1987

Mitochondrial DNA in Candida pintolopesii, a yeast indigenous to the surface of the secreting epithelium of the murine stomach.

Candida pintolopesii 108-1 is an indigenous yeast which colonizes the surface of the secreting gastric mucosa of mice. We have been exploring the aerobic respiratory capacities of this organism in reference to its capacity to colonize the stomach surface, an environment that could contain little oxygen for microbial growth. In this paper, we report mitochondrial DNA and membranes in cells of a strain of this yeast isolated from the gastric epithelium of a mouse and compare the findings with those made by other investigators in studies of Saccharomyces cerevisiae. Putative mitochondrial DNA was isolated from crude lysates of C. pintolopesii and S. cerevisiae as fluorescing bands in CsCl gradients containing 4',6-diamidino-2-phenylindole. The DNA from C. pintolopesii hybridized with a 32P-labeled DNA probe for the 21S rRNA gene encoded by mitochondrial DNA in S. cerevisiae. Postvital cell staining with 4',6-diamidino-2-phenylindole and rhodamine 123 revealed mitochondrial DNA and membranes, respectively, in the cytoplasm of intact C. pintolopesii cells. The staining patterns were generally similar to those reported for S. cerevisiae. Finally, structures similar to those reported to be mitochondria in electron micrographs of S. cerevisiae were seen in preparations of C. pintolopesii cells examined by transmission electron microscopy. These data confirm findings from studies of its respiratory capacity published earlier that a strain of C. pintolopesii isolated directly from its native habitat has functional mitochondria.

Aerobiosis↗

PubMed1992

[Emission and control of gases and odorous substances from animal housing and manure depots].

Agricultural animal production in increasingly regarded as a source of gases which are both aggravating and ecologically harmful. An overview of the origin, number and quantity of trace gases emitted from animal housing and from manure stores is presented and possible means of preventing or reducing them are discussed. Of the 136 trace gases in the air of animal houses, odorous substances, ammonia and methane are most relevant to the environment. The role played by the remaining gases is largely unknown. Quantitative information is available for 23 gases. The gases are emitted principally from freshly deposited and stored faeces, from animal feed and from the animals themselves. Future work should determine sources and quantities of the gases emitted from animal housing more precisely and should aim to investigate the potential of these gases to cause damage in man, animals and environment. Odorous substances have an effect on the area immediately surrounding the animal housing. They can lead to considerable aggravation in humans. For years, VDI1 guidelines (3471/72), which prescribe distances between residential buildings and animal housing, have been valuable in preventing odour problems of this kind. Coverings are suitable for outside stores. The intensity of the odour from animal housing waste air increases from cattle through to hens and pigs; it is also further affected by the type of housing, the age of the animals and the purpose for which they are being kept. Methods of cleaning waste air (scrubbers/biofilters) are available for problematic cases. The need for guidelines to limit emissions from individual outside manure stores (lagoons) is recognised. Total ammonia emissions from animal production in the Federal Republic of Germany (up to 1989) are estimated at approximately 300,000 to 600,000 t/year. There is a shortage of satisfactory and precise research on the extent of emissions, in particular on those from naturally ventilated housing. It is calculated that between 12 and 21 kg/ha of nitrogen a year enter the soil via the air, the average of which is higher than the average "critical loads" for most natural habitats. Ammonia has a direct effect on the trees in the area surrounding animal housing and is transported long distances through the air causing eutrophication and acidification of water and vegetation. This frequently results in changes in plant sociology. Reduction measures must begin with the housing and manure removal systems and with feeding and management.(ABSTRACT TRUNCATED AT 400 WORDS)

Air Pollution↗

PubMedDate not supplied

[Population biology of parasites: current status and prospects].

The present state of parasite population biology is reviewed with special reference to parasites of fish. Mathematical models have provided a coherent body of theory which is supported by many laboratory investigations. There is nevertheless some disagreement between predictions based on this theory and data obtained from investigations of natural parasite populations. It is suggested that this is partly due to the oversimplifications and limitations of the models, and partly to the unsystematic approach of many field investigations and the resulting shortage of data of the right sort. In freshwater habitats disagreement may also be due to the rapid and extensive changes that are taking place in the habitats themselves as a direct consequence of human activities. Future developments should involve models becoming more realistic, and field investigations being conducted in a more systematic and analytical manner in order to obtain quantitative measurements of the essential population parameters.

Animals↗

PubMed1987

Resistance of California ground squirrels (Spermophilus beecheyi) to the venom of the northern Pacific rattlesnake (Crotalus viridis oreganus): a study of adaptive variation.

Recent studies have documented natural resistance to snake venom in a number of diverse mammalian species. The present paper documents for the first time variation in such resistance within one single species, the California ground squirrel (Spermophilus beecheyi). This species is a frequent prey of the northern Pacific rattlesnake (Crotalus viridis oreganus) in certain habitats. Venom resistance was tested directly in two populations of ground squirrels by injection of 1-40 mg/kg venom doses. One population was obtained from a habitat with a high rattlesnake density; the other population came from a rattlesnake-free habitat. Dramatic differences in the response to venom between these populations were manifested, based on a variety of criteria, such as mortality, necrosis and healing time. Resistance to venom was also examined by LD50 tests in groups of mice pre-injected with ground squirrel sera from three rattlesnake-adapted California populations and a non-adapted Arctic population (S. parryii) from snake-free central Alaska. The California ground squirrel sera were 3.3-5.3 times more effective in the in vivo neutralization of venom than the sera from Arctic ground squirrels. Moreover, the level of protection by the sera as reflected by the LD50 values was highly correlated (P less than 0.005) with the level of in vitro squirrel serum-venom binding as quantified by radioimmunoassay (RIA). A subsequent RIA revealed that binding levels of sera from 14 California ground squirrel populations correlated significantly (P less than 0.025) with local rattlesnakes densities; i.e. sera pools from populations sympatric with rattlesnakes exhibited the highest binding, whereas populations living in habitats where rattlesnakes are rare or absent typically exhibited the lowest binding levels, several of which approximated the Arctic control. Taken together, these results demonstrate intraspecific variation that is probably the result of differential natural selection due to northern Pacific rattlesnakes. This intraspecific variation should be taken into consideration when testing for natural resistance in wild-caught species.

Adaptation, Physiological↗

PubMed1986

Comparative red blood cell metabolism in three wallaby species, Macropus eugenii, Macropus parma and Thylogale thetis (Macropodidae: Marsupialia).

Aspects of red blood cell metabolism were compared among three species of small macropodid marsupials from different habitats. Packed cell volume (PCV), erythrocyte reduced glutathione (GSH) concentration and GSH regeneration rates were similar in all three species. The Parma wallaby had very low red cell potassium levels compared to the other species studied. The Tammar wallaby had higher rates of glucose consumption and lactate production in vitro at both pH 7.4 and 8.2 than did the Parma and significantly lower adenosine triphosphate (ATP) levels than the other species. These findings are consistent with preliminary reports published previously. The differences noted cannot be directly related to differences in the habitats of the species.

Adenosine Triphosphate↗

PubMed1989

Laboratory study of competition between United States strains of Aedes albopictus and Aedes aegypti (Diptera: Culicidae).

Mosquito abatement workers in Houston, Tex., and New Orleans, La., have observed that the recent introduction of Aedes albopictus (Skuse) has been accompanied by a decline and virtual disappearance of Ae. aegypti (L.). This suggests competitive displacement but contradicts the direction of displacement observed in native habitats of Ae. albopictus. The paper reports a series of laboratory studies on competition between U.S. strains of the two species. Larval survivorship, size, and development time were monitored in increasing densities of pure and mixed cultures of the two species under limited and optimal diets. Oviposition preferences were examined by offering gravid females cups containing first or fourth instars of either species. Ethological isolation was studied by simultaneously offering virgin females of one species to males of both species and monitoring courtship behavior as well as rates of oviposition, percentage of hatch, and embryonation. The results of the larval competition studies suggest that interspecific competition increased development time only slightly and had no effect on survival of Ae. albopictus. Competition increased survival in Ae. aegypti. Size of both species was influenced by interspecific competition, but the magnitude and direction of the effect was inconsistent between strains and diets such that neither species emerged consistently larger. The results of the oviposition study indicated a higher fecundity in Ae. aegypti but otherwise demonstrated that both species oviposit without regard to the presence, age, or species of larvae in the oviposition container. The ethological isolation tests demonstrated that Ae. aegypti males were more sexually aggressive than males or Ae. albopictus. However, Ae. albopitus females placed with increasing densities of Ae. aegypti males demonstrated no decrease in rates of oviposition, and eggs laid showed equal rates of hatch and embryonation. In general, the results do not suggest that the U.S Ae. albopictus population is inherently more competitive in the laboratory than Ae. aegypti. Other reasons for the observed decline in Ae. aegypti in the United States are discussed.

Aedes↗

PubMed1969

Rumen microbial ecology in mule deer.

Mule deer rumen microbial populations from animals in the natural habitat in Utah and from captive deer fed various rations were studied. The microorganisms were characterized on the basis of morphology and Gram reaction. Rumen samples contained 13 identifiable types of bacteria and one genus of ciliate protozoa (Entodinium). Highest rumen bacterial populations were produced on rations containing barley. No differences in proportions of ruminal bacteria in the various morphological groups could be detected when animals were fed either natural browse plants or alfalfa hay. The total numbers of bacteria were similar for animals feeding on controlled diets of browse or hay and those in the natural habitat. Numbers of some bacterial types were directly related to ciliate protozoal numbers, whereas others were inversely related. Highest rumen ciliate protozoal populations were observed on rations containing barley. No differences in protozoal populations were noted between diets containing only browse or hay. Seasonal variations were noted in ciliate protozoal numbers from deer feeding in the natural habitat. The total number of ciliate protozoa decreased in the fall and winter and remained low until spring. There were indications that salt in the deer diet favorably affected rumen ciliate protozoa. Rather than revealing direct deer management applications, this study serves to stimulate and illuminate new approaches to research in range and wildlife nutrition.

Animal Feed↗

PubMed1992

Eye regionalization and spectral tuning of retinal pigments in insects.

The spatial and spectral properties of an eye can often be directly linked to the behaviour and habitat of the animal. In a honey bee (Apis mellifera) society, the drones use the well-developed dorsal part of the eye to detect the queen against the sky during her nuptial flight. Recently it has become clear that the dorsal area of the drone's eye serves its task by cleverly combining a number of optical mechanisms, thus achieving a high spatial acuity as well as a high sensitivity precisely in the wavelength range of interest--the ultraviolet to blue range. Since the various optical specializations in the drone eye have now been recognized, they can be traced in the eyes of other species: thus, the drone eye serves as a model to give a better understanding of the relationship between structure and function of compound eyes in particular, but also of visual systems in general.

Animals↗

PubMed1979

[Orientation of the catfish in uniform and nonuniform electric fields].

Experiments with conditioning revealed that catfish showed compass orientation with precision about 20 degrees using a direction of homogeneous horizontally directed weak electric field with current density of 1.5 . 10(-11) A/mm2 in water with a specific resistance of 15 Ohm-m. Similar fields occur in their habitat. The catfish used the current density gradient for directed movements in the unhomogenous field. The lowest current density gradient in which the catfish showed the orientation behaviour proved to be 3.6 x 10(-12) A/mm2 per 1-mm distance. The possible mechanism of electro-orientation and its functional significance, are discussed.

Animals↗

PubMed1991

Vertical distribution of Psychoda alternata (Diptera:Psychodidae) in soil receiving wastewater utilized for turf cultivation.

Vertical distribution of immature Psychoda alternata in soil to a depth of 15 cm was studied in Jacksonville, FL. Samples were randomly taken from large circular land areas receiving a brewery wastewater utilized for commercial turf cultivation and included turfed and bare habitats. Total organic matter was quantified at various soil depths. Overall, 88.5 and 95.8% larvae and 91.3 and 94.0% pupae were recovered from the top 2.5 cm of soil at turfed and bare habitats, respectively. The highest concentration of total organic matter at both habitat types was in the top 2.5 cm. There were strong positive relationships between the number of larvae and pupae and total organic matter, indicating highest concentrations of immatures in nutrient-rich topsoil with an abundant supply of larval food. We suggest that insecticidal treatment directed against immature P. alternata breeding in such habitats need not penetrate to a depth of more than a few centimeters to affect almost all of the population of this pestiferous insect.

Animals↗

PubMed1985

Vibrio alginolyticus conjunctivitis. First reported case.

A gravely ill patient had Vibrio alginolyticus conjunctivitis develop, possibly from contact with seashell fragments. It is believed to be the first reported instance of ocular infection by this organism. Marine Vibrio organisms must be considered as potential sources of ocular infection in patients with direct or indirect exposure to salt water habitats, or in patients who are immunocompromised.

Aged↗

PubMed1990

Geographical distribution of contaminants and productivity measures of herring gulls in the Great Lakes: Lake Erie and connecting channels 1978/79.

The distribution and size of colonies, residue levels of DDE, DDT, HCB, dieldrin, mirex and PCBs in eggs, productivity and eggshell thickness were determined for herring gulls at 14 sites in Lake Erie and connecting channels. The centre of distribution for breeding herring gulls was the Western Basin where approximately 90% of the 6200 nests in the study area were located. Seven of 22 colonies showed an average annual population increase of 48.3%. Most of the increase in breeding herring gulls on Lake Erie is directly associated with sites that have undergone habitat modification by man. Levels of PCBs and DDE ranged from 35 to 140 ppm (wet weight) and from 2.8 to 9.4 ppm, respectively; all other residues were less than 0.49 ppm. Most organochlorine residue levels were highest in eggs from colonies in or near the Niagara or Detroit Rivers. Mirex residues were greatest in the Niagara River and decreased significantly to the west. PCB residues were greatest in the Detroit River and decreased significantly to the east. The lowest levels generally came from colonies in the Sandusky Basin and near Pelee Island in western Lake Erie. Discriminant function analysis of six organochlorine contaminants correctly classified 90% or more of the eggs from up to four colonies in one or more years. Levels of PCBs and HCB appeared to have the greatest discriminating power. Herring gull productivity at all colonies (1-1.7 young gulls/pair) was normal and showed no significant geographical variation. Eggshell thickness was greatest in colonies in the Sandusky Basin and least in colonies in the Detroit River and extreme west end of the lake; mean eggshell thickness was 0.350 +/- 0.02 mm (6.7% thinning), which was weakly, but significantly correlated to DDE concentration. The variation in contaminants in herring gull eggs on a Basin basis (i.e., Western, Eastern, Sandusky, etc.) paralleled those known for sediments, water and fish. Thus, we suggest that in addition to its role as an indicator of lake-wide contamination of the Great Lakes, the herring gull, under some circumstances, may function as an indicator of "regional" contamination. This is an important distinction as it improves the geographical specificity of the herring gull as an indicator species on the Great Lakes, where it is a non-migratory species.

Animals↗

PubMed1992

Conservation genetics of whales and dolphins.

Whales and dolphins (cetaceans) are found in all the world's oceans and in some of the major rivers, yet little is known about the distribution and behaviour of many species. At the same time, cetaceans are under threat from a variety of pressures including direct and indirect takes, pollution, and competition for habitat and prey. To ensure their long-term survival it will be necessary to preserve genetic diversity through the identification and protection of differentiated populations, the assessment of variation within local populations, and through a better understanding of reproductive and dispersal behaviour. The application of molecular genetic techniques is helping to provide answers to some of these previously intractable questions. Early results suggest few consistent patterns. Obvious geographic boundaries correlate to genetic distance in some species, and not in others. Furthermore, morphological variation within species can be fairly extensive without correlating to genetic distance, or relatively minor between morphotypes that are as genetically distinct as some species. These examples emphasize the need for further study.

Animals↗

PubMed1975

The influence of selective logging on primates and some other animals in East Kalimantan.

A brief survey was conducted in East Kalimantan, Indonesia, to determine the influence of selective logging operations on primate populations. Data were also collected on some birds and squirrels. Selective logging that causes only moderate habitat disturbance does not seem to result in a significant decrease in the densities of several primate species. Whereas some species adjust readily to moderately disturbed habitats, other species may have difficulty in maintaining a breeding population in logged areas. A review of the literature plus our own data suggest that rain forest birds and squirrels seem to be the most disrupted by selective logging of their habitats. While some of the other mammals are directly harmed by selective logging, others are endangered only by the human encroachment that often follows. Suggestions regarding enlightened tropical forestry practices, additional studies of the influence of selective logging, and the establishment of forest preservation areas are also discussed.

Animals↗

PubMed1987

Honeydew of aphids as a source of sugar for Phlebotomus ariasi.

Wild-caught Phlebotomus ariasi Tonnoir, starved until their sugar meals had been digested, were caged for 24 h with plants or plants infested with aphids and then tested for fructose, a constituent of plant sap. No evidence was found that the flies took sap directly from nine types of plants present in their habitat. About two-thirds of flies caged with oak (Quercus ilex L.) infested with an aphid [Lachnus roboris (L.)] and about a fifth kept with leaves of the french bean (Phaseolus vulgaris L.) infested with an aphid took honeydew. Experiments with three other aphid species gave negative results. Of sandflies caught in an oak tree infested with aphids, half of the females and three-quarters of the males contained fructose. Tests on females caught in a house and grouped according to state of engorgement showed that, having taken blood, the females stop taking sugar until the bloodmeal is completely digested. It is predicted that honeydews are important in the development of Leishmania infantum Nicolle in the gut of P. ariasi.

Animals↗