scholarly journals Environmental factors determining growth of salamander larvae: A field study

2015 ◽  
Vol 61 (3) ◽  
pp. 421-427 ◽  
Author(s):  
Laura Limongi ◽  
Gentile Francesco Ficetola ◽  
Giuseppe Romeo ◽  
Raoul Manenti
Keyword(s):  
Field Study ◽  
Environmental Variables ◽  
Larval Growth ◽  
Experimental Studies ◽  
Field Studies ◽  
Development Rate ◽  
Biotic Factors ◽  
Natural Conditions ◽  
Fire Salamander ◽  
Salamander Larvae

Abstract Larval growth and survival of organisms are strongly influenced by abiotic and biotic factors, as demonstrated by experimental studies performed under controlled laboratory or semi-natural conditions. Even if they have many advantages, experiments cannot cover the full complexity of natural conditions and field studies are needed for a better understanding of how environmental variation determines growth and development rate. Fire salamander Salamandra salamandra females give birth to larvae in a variety of habitats, both epigean and subterranean. In caves, salamander larvae successfully grow and metamorphose, but their growth is more than three times longer than in epigean streams and factors determining these differences require investigation. We performed a field study to understand the factors related to the growth of fire salamander larvae in different environmental conditions, evaluating the relationship between environmental features and larval growth and differences between caves and epigean spring habitats. Both caves and epigean larvae successfully grew. Capture-mark-recapture allowed to individually track individuals along their whole development, and measure their performance. Growth rate was significantly affected by environmental variables: larvae grew faster in environments with abundant invertebrates and few conspecifics. Taking into account the effect of environmental variables, larval growth was significantly lower in caves. Food availability plays a different effect in the two environments. Larval growth was positively related to the availability of invertebrates in epigean sites only. The development rate of hypogeous populations of salamanders is slower because of multiple parameters, but biotic factors play a much stronger role than the abiotic ones.

Effects of Trust and Threat Messaging on Academic Cheating: A Field Study

2021 ◽  
pp. 095679762097751
Author(s):  
Li Zhao ◽  
Jiaxin Zheng ◽  
Haiying Mao ◽  
Xinyi Yu ◽  
Jiacheng Ye ◽  
...  
Keyword(s):  
Field Study ◽  
Academic Integrity ◽  
Large Scale ◽  
Theoretical Foundation ◽  
Empirical Evaluation ◽  
Psychological Theory ◽  
Field Studies ◽  
Educational Institutions ◽  
Academic Cheating ◽  
College Classrooms

Morality-based interventions designed to promote academic integrity are being used by educational institutions around the world. Although many such approaches have a strong theoretical foundation and are supported by laboratory-based evidence, they often have not been subjected to rigorous empirical evaluation in real-world contexts. In a naturalistic field study ( N = 296), we evaluated a recent research-inspired classroom innovation in which students are told, just prior to taking an unproctored exam, that they are trusted to act with integrity. Four university classes were assigned to a proctored exam or one of three types of unproctored exam. Students who took unproctored exams cheated significantly more, which suggests that it may be premature to implement this approach in college classrooms. These findings point to the importance of conducting ecologically valid and well-controlled field studies that translate psychological theory into practice when introducing large-scale educational reforms.

scholarly journals An aquatic vertebrate can use amino acids from environmental water

2016 ◽  
Vol 283 (1839) ◽  
pp. 20160996 ◽  
Author(s):  
Noboru Katayama ◽  
Kobayashi Makoto ◽  
Osamu Kishida
Keyword(s):  
Amino Acids ◽  
Organic Matter ◽  
Amino Acid ◽  
Dissolved Organic Matter ◽  
Larval Growth ◽  
Environmental Water ◽  
Acid Solutions ◽  
Aquatic Vertebrates ◽  
Amino Acid Solutions ◽  
Salamander Larvae

Conventional food-web theory assumes that nutrients from dissolved organic matter are transferred to aquatic vertebrates via long nutrient pathways involving multiple eukaryotic species as intermediary nutrient transporters. Here, using larvae of the salamander Hynobius retardatus as a model system, we provide experimental evidence of a shortcut nutrient pathway by showing that H. retardatus larvae can use dissolved amino acids for their growth without eukaryotic mediation. First, to explore which amino acids can promote larval growth, we kept individual salamander larvae in one of eight different high-concentration amino acid solutions, or in control water from which all other eukaryotic organisms had been removed. We thus identified five amino acids (lysine, threonine, serine, phenylalanine, and tyrosine) as having the potential to promote larval growth. Next, using 15 N-labelled amino acid solutions, we demonstrated that nitrogen from dissolved amino acids was found in larval tissues. These results suggest that salamander larvae can take up dissolved amino acids from environmental water to use as an energy source or a growth-promoting factor. Thus, aquatic vertebrates as well as aquatic invertebrates may be able to use dissolved organic matter as a nutrient source.

scholarly journals Comparison of different Parameters of Heart Rate Frequency of Tasks Performed during Aircraft Open-Basket Ground Deicing Activities

2020 ◽  
Vol 4 (6) ◽  
Author(s):  
Landau K
Keyword(s):  
Heart Rate ◽  
Cardiac Output ◽  
Field Study ◽  
Small Sample Size ◽  
Field Studies ◽  
Small Sample ◽  
Upper Body ◽  
Evaluation Measure ◽  
Cardiac Cost ◽  
Working Heart

Plane deicing is mandatory to insure safe plane take-off. Previous human factors studies have shown that open-basket deicing activity can be improved. The objective of the paper is to compare heart rate assessment models within a field study with numerous influencing variables and small sample size as well as to deepen our understanding of the most demanding openbasket tasks using cardiac output. A field study in a Canadian centered plane deicing facility was conducted in 2016-2017. 12 participants contributed to a thorough description and analysis of open-basket deicing activities. Respiratory and cardiac output of these participants was collected using Hexoskin vests. Working heart rate, heart rate reserves as well as calculations of absolute cardiac cost were done. Working heart rate (WHR), Heart Rate Reserve (HRR) and Absolute Cardiac Cost (ACC) do not behave uniformly for the majority of participants. In field studies with a large number of influencing variables on the heart rate, it is usually not sufficient to consider one single evaluation measure like WHR. In the interest of protecting employees, it seems to make sense to use the more cautious measures HRR or ACC as parameters instead of WHR. Superimposed activities (e.g. forced postures and dynamic use of upper body) have a significant effect on heart rate increases. In 8 out of 11 cases we have fatigue-related increases in heart rate over the observation period. Similar studies need to be conducted in other aircraft deicing facilities.

scholarly journals The watching eyes effect on charitable donation is boosted by fewer people in the vicinity

2016 ◽  
Vol 7 (2) ◽  
pp. 9-12
Author(s):  
Ryo Oda ◽  
Ryota Ichihashi
Keyword(s):  
Field Study ◽  
Charitable Giving ◽  
Field Experiments ◽  
Field Studies ◽  
Prosocial Behaviors ◽  
Charitable Donation ◽  
Charitable Donations ◽  
Large Groups

Previous field experiments have found that artificial surveillance cues facilitated prosocial behaviors such as charitable donations and littering. Several previous field studies found that the artificial surveillance cue effect was stronger when few individuals were in the vicinity; however, others reported that the effect was stronger in large groups of people. Here, we report the results of a field study examining the effect of an artificial surveillance cue (stylized eyes) on charitable giving. Three collection boxes were placed in different locations around an izakaya (a Japanese-style tavern) for 84 days. The amount donated was counted each experimental day, and the izakaya staff provided the number of patrons who visited each day. We found that the effect of the stylized eyes was more salient when fewer patrons were in the izakaya. Our findings suggest that the effect of the artificial surveillance cue is similar to that of “real” cues and that the effect on charitable giving may weaken when people habituate to being watched by “real” eyes. 

scholarly journals Effects of Environmental Variables on some Physiological Responses of Microtus montanus Under Natural Conditions

1982 ◽  
Vol 6 ◽  
pp. 66-68
Author(s):  
Aelita Pinter
Keyword(s):  
Environmental Variables ◽  
National Park ◽  
Reproductive Activity ◽  
Natural Conditions ◽  
Term Study ◽  
Microtus Montanus ◽  
Long Term Study ◽  
Microtine Rodents ◽  
Different Seasons

Cyclic fluctations in the popu]ation density of rnicrotine rodents have been known since antiquity. However, factors responsible for this phenomenon are not known. The objectives of this long term study are essentially threefold: 1. characterize those environmental variables that might affect Microtus montanus in different seasons of the year; 2. record the growth, maturation and reproductive activity of the voles under natural conditions; and 3. determine the maturational, as well as, the seasonal pelage changes of these rodents. The data resulting from the execution of the above objectives would be correlated in an attempt to determine the causes undedying the multiannual fluctuations in the population density of these microtine rodents in Grand Teton National Park.

scholarly journals Experimental studies illuminate the cultural transmission of percussive technologies in Homo and Pan

2015 ◽  
Vol 370 (1682) ◽  
pp. 20140359 ◽  
Author(s):  
Andrew Whiten
Keyword(s):  
Social Learning ◽  
Tool Use ◽  
Cultural Transmission ◽  
Experimental Studies ◽  
Field Studies ◽  
Learning Processes ◽  
Cognitive Context ◽  
The Social ◽  
Special Power ◽  
Social Learning Processes

The complexity of Stone Age tool-making is assumed to have relied upon cultural transmission, but direct evidence is lacking. This paper reviews evidence bearing on this question provided through five related empirical perspectives. Controlled experimental studies offer special power in identifying and dissecting social learning into its diverse component forms, such as imitation and emulation. The first approach focuses on experimental studies that have discriminated social learning processes in nut-cracking by chimpanzees. Second come experiments that have identified and dissected the processes of cultural transmission involved in a variety of other force-based forms of chimpanzee tool use. A third perspective is provided by field studies that have revealed a range of forms of forceful, targeted tool use by chimpanzees, that set percussion in its broader cognitive context. Fourth are experimental studies of the development of flint knapping to make functional sharp flakes by bonobos, implicating and defining the social learning and innovation involved. Finally, new and substantial experiments compare what different social learning processes, from observational learning to teaching, afford good quality human flake and biface manufacture. Together these complementary approaches begin to delineate the social learning processes necessary to percussive technologies within the Pan – Homo clade.

Intercohort size structure dynamics of fire salamander larvae in ephemeral habitats: a mesocosm experiment

Oecologia ◽  
2015 ◽  
Vol 179 (2) ◽  
pp. 425-433 ◽  
Author(s):  
Asaf Sadeh ◽  
Antonina Polevikov ◽  
Marc Mangel ◽  
Leon Blaustein
Keyword(s):  
Size Structure ◽  
Mesocosm Experiment ◽  
Structure Dynamics ◽  
Fire Salamander ◽  
Salamander Larvae ◽  
Ephemeral Habitats

Assessment of Change after Long-Term Psychoanalytic Group Treatment: Presentation of a Field Study of Outpatients from Private Psychiatric Practice

2000 ◽  
Vol 33 (3) ◽  
pp. 373-396 ◽  
Author(s):  
Steinar Lorentzen
Keyword(s):  
Clinical Practice ◽  
Clinical Research ◽  
Field Study ◽  
Research Methods ◽  
Group Treatment ◽  
Private Practice ◽  
Experimental Studies ◽  
Effectiveness Study ◽  
Efficacy Studies

The main purpose of this article is to underline the importance of doing clinical research on long-term, dynamic group psychotherapy as it is carried out in practice (effectiveness study). After a review of the outcome literature, which mainly consists of experimental studies (efficacy studies), an effectiveness study from a private practice will be described with some preliminary results. Experiences from implementation of a research project in clinical practice are presented and the strengths and limitations of the two research methods are discussed.

A field study on the biology of the underground grass caterpillar, Oncopera Fasciculata (Walker) (Lepidoptera: Hepialidae), in South Australia.

1954 ◽  
Vol 2 (2) ◽  
pp. 193 ◽  
Author(s):  
PE Madge
Keyword(s):  
Field Study ◽  
Light Stimulus ◽  
Insect Pest ◽  
South Australia ◽  
Field Studies ◽  
Surface Growth ◽  
Annual Grasses ◽  
Lower South

This paper describes field studies on the biology and behaviour of Oncopera fasciculata (Walker), an important insect pest of improved pastures in the lower south-east of South Australia and the central and western districts of Victoria. Moths fly at dusk during September-October and mate mainly on upright grasses during these flights. The onset of flights seems to be related to a light stimulus but no correlation could be found from the data collected. Eggs are laid on the ground under pasture, where the female shelters at night and during the day; most eggs are laid within 24 hr after mating. Larvae appear in from 3 to 5 wk and live for a short while in communities at the surface of the ground under silken webbing before building individual vertical tunnels in the soil. Larvae emerge from their tunnels along silken runways to feed on surface growth. Annual grasses and clovers are more susceptible to attack than perennials. Feeding continues from October to July and visible damage appears about May, depending upon seasonal conditions. Prepupae appear in July and pucae during July-September.

Developmental costs of yellow colouration in fire salamanders and experiments to test the efficiency of yellow as a warning colouration

2020 ◽  
Vol 41 (3) ◽  
pp. 373-385 ◽  
Author(s):  
Barbara A. Caspers ◽  
E. Tobias Krause ◽  
Isabelle Hermanski ◽  
Christopher Wiesbrock ◽  
Friedrich-Wilhelm Kastrup ◽  
...  
Keyword(s):  
Predation Risk ◽  
Carabid Beetles ◽  
Colour Pattern ◽  
Natural Habitats ◽  
Yellow Colour ◽  
Risk Of Predation ◽  
Fire Salamander ◽  
Food Conditions ◽  
In Fire ◽  
Salamander Larvae

Abstract Warning colouration reduces predation risk by signalling or mimicking the unpleasantness of prey and therefore increases survival. We tested in two experiments the evolutionary costs and benefits of the yellow colour pattern in fire salamanders (Salamandra salamandra), which display a yellow/black colour pattern usually associated with toxic alkaloids. Our first experiment aimed to test whether the development of colouration is condition dependent and thus related to developmental costs, i.e. influenced by resource availability during the developmental process. Therefore, we reared fire salamander larvae under different nutritional conditions and compared the relative amount of yellow they developed after metamorphosis. Fire salamander larvae reared under limited food conditions had a lower proportion of yellow following metamorphosis than control larvae reared under superior food conditions. In a second experiment we tested whether the proportion of yellow has an impact on the risk of being attacked using artificial models. We tested, in salamander-free and salamander-occupied natural habitats, whether artificial clay models with different proportions of yellow and black receive different attack rates from potential predators (birds, mammals, insects). In clay models the proportion of yellow and the site had a significant effect on predation risk. Models with larger amounts of yellow had fewer bite marks from predators such as carabid beetles and birds, but only in sympatry with salamanders. In conclusion, the early expression of conspicuous colouration seems to be condition dependent and therefore potentially costly. Furthermore, the yellow colouration of fire salamanders act as a signal that potentially reduces their risk of being attacked by predators. Thus, the yellow colouration of fire salamanders seems to represent an adaptive trait that reduces the risk of predation, which can be expressed in higher quantity by individuals of a certain condition.

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