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This article discusses a recent study that examines the role of the Tasmanian devil, an endangered species, in nutrient cycling, soil microbial diversity, forest productivity, and carbon storage in Tasmanian Eucalypt forests. The study found that the scavenging traits of the Tasmanian devil, particularly its consumption of bone material, contribute to the mobilization of critical nutrients in the forest ecosystem. The research suggests that the presence of Tasmanian devils and their scat may help buffer the forests from climate-induced changes in soil microbe, nutrient, and carbon cycling processes. These findings highlight the importance of biodiversity in maintaining ecosystem functions and processes, especially in the face of climate change and species loss. [Extracted from the article]

Foraging decisions shape the structure of food webs. Therefore, a behavioural shift in a single species can potentially modify resource‐flow dynamics of entire ecosystems. To examine this, we conducted a field experiment to assess foraging niche dynamics of semi‐arboreal brown anole lizards in the presence/absence of predatory ground‐dwelling curly‐tailed lizards in a replicated set of island ecosystems. One year after experimental translocation, brown anoles exposed to these predators had drastically increased perch height and reduced consumption of marine‐derived food resources. This foraging niche shift altered marine‐to‐terrestrial resource‐flow dynamics and persisted in the diets of the first‐generation offspring. Furthermore, female lizards that displayed more risk‐taking behaviours consumed more marine prey on islands with predators present. Our results show how predator‐driven rapid behavioural shifts can alter food‐web connectivity between oceanic and terrestrial ecosystems and underscore the importance of studying behaviour‐mediated niche shifts to understand ecosystem functioning in rapidly changing environments. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate and compare feeding responses of the non-native and native bivalves, the dark false mussel Mytilopsis leucophaeata and the scorched mussel Brachidontes darwinianus, respectively, by offering different concentrations of seston from the coastal lagoon where these species coexist after dark false mussel introduction (Rodrigo de Freitas Lagoon, Rio de Janeiro-Brazil). For this purpose, independent laboratory experiments were carried out under five concentrations of seston to test the differences in clearance and ingestion rates of bivalves as a function of increasing concentrations of suspended particulate matter (SPM) on seston. In addition, from the integrated analysis of data obtained in experiments, it can be inferred about the efficiency levels of these species to remove SPM from seston and their effects on water turbidity and nutrient concentrations (total carbon, nitrogen, and phosphorus). Our hypothesis was that the non-native bivalve is more efficient to clear and ingest SPM from seston compared to the native one, which may lead to competitive advantages to the successful invasion of M. leucophaeata in coastal lagoons. Native species did not show a significant difference in clearance and ingestion rates with increasing concentrations of seston. Whereas the non-native bivalve showed a slight tendency to increase its clearance and ingestion rates with the increase in seston concentrations, evidencing its plasticity to adjust its feeding responses. The native bivalve was significantly more efficient to clear and ingest SPM at the lower seston concentration (i.e., close to natural concentrations found in the lagoon) compared to the non-native bivalve, which, on the other hand, showed a significant increase in its ingestion rates at the higher concentration tested (140 mg SPM L-1). Thus, the present results did not suggest food competition between the non-native M. leucophaeata and the native B. darwinianus in the introduced system. However, M. leucophaeata increased its feeding response with experimental increment in seston concentration, which suggests species ability to benefit from conditions of increased inputs of organic matter and higher primary production that could mediate its establishment in introduced systems. [ABSTRACT FROM AUTHOR]

Salinization of freshwater ecosystems is one of the major challenges imposed largely by climate change and excessive water abstraction for irrigated crop farming. Understanding how aquatic ecosystems respond to salinization is essential for mitigation and adaptation to the changing climate, especially in arid landscapes. Field observations provide invaluable data for this purpose, but they rarely include sufficient spatial and temporal domains; however, experimental approaches are the key to elucidating complex ecosystem responses to salinization. We established similar experimental mesocosm facilities in two different climate zones in Turkey, specifically designed to simulate the effects of salinization and climate change on shallow lake ecosystems. These facilities were used for two case-study experiments: (1) a salinity gradient experiment consisting of 16 salinity levels (range: 0–50 g/L); and (2) a heatwave experiment where two different temperature regimes (no heatwave and +6 °C for two weeks) were crossed with two salinity levels (4 and 40 g/L) with four replicates in each treatment. The experiments lasted 8 and 2 months, respectively, and the experimental mesocosms were monitored frequently. Both experiments demonstrated a significant role of salinization modulated by climate on the structure and function of lake ecosystems. Here, we present the design of the mesocosm facilities, show the basic results for both experiments and provide recommendations for the best practices for mesocosm experiments conducted under saline/hypersaline conditions. [ABSTRACT FROM AUTHOR]

Marine environments are expected to be one of the most affected ecosystems by climate change, notably with increasing ocean temperature and ocean acidification. In marine environments, microbial communities provide important ecosystem services ensuring biogeochemical cycles. They are threatened by the modification of environmental parameters induced by climate change that, in turn, affect their activities. Microbial mats, ensuring important ecosystem services in coastal areas, are well-organized communities of diverse microorganisms representing accurate microbial models. It is hypothesized that their microbial diversity and metabolic versatility will reveal various adaptation strategies in response to climate change. Thus, understanding how climate change affects microbial mats will provide valuable information on microbial behaviour and functioning in changed environment. Experimental ecology, based on mesocosm approaches, provides the opportunity to control physical-chemical parameters, as close as possible to those observed in the environment. The exposure of microbial mats to physical-chemical conditions mimicking the climate change predictions will help to decipher the modification of the microbial community structure and function in response to it. Here, we present how to expose microbial mats, following a mesocosm approach, to study the impact of climate change on microbial community. [ABSTRACT FROM AUTHOR]

An evolutionary debate contrasts the importance of genetic convergence versus genetic redundancy. In genetic convergence, the same adaptive trait evolves because of similar genetic changes. In genetic redundancy, the adaptive trait evolves using different genetic combinations, and populations might not share the same genetic changes. Here we address this debate by examining single nucleotide polymorphisms (SNPs) associated with the rapid evolution of character displacement in Anolis carolinensis populations inhabiting replicate islands with and without a competitor species (1Spp and 2Spp islands, respectively). We identify 215-outliers SNPs that have improbably large FST values, low nucleotide variation, greater linkage than expected and that are enriched for genes underlying animal movement. The pattern of SNP divergence between 1Spp and 2Spp populations supports both genetic convergence and genetic redundancy for character displacement. In support of genetic convergence: all 215-outliers SNPs are shared among at least three of the five 2Spp island populations, and 23% of outlier SNPS are shared among all five 2Spp island populations. In contrast, in support of genetic redundancy: many outlier SNPs only have meaningful allele frequency differences between 1Spp and 2Spp islands on a few 2Spp islands. That is, on at least one of the 2Spp islands, 77% of outlier SNPs have allele frequencies more similar to those on 1Spp islands than to those on 2Spp islands. Focusing on genetic convergence is scientifically rigorous because it relies on replication. Yet, this focus distracts from the possibility that there are multiple, redundant genetic solutions that enhance the rate and stability of adaptive change. [ABSTRACT FROM AUTHOR]

It is generally assumed that the larger the bottle volume, the longer the duration of phytoplankton microcosm experiments. We hypothesize that volume and duration are independent, as volume does not regulate the extension of the exponential growth phase. We conducted two microcosm experiments using 1, 2, and 8 L bottles, inoculated with phytoplankton collected in the Ria Formosa lagoon (SE Portugal) and incubated for 1, 2, 4, and 8 days. Phytoplankton net growth rates were estimated using chlorophyll a concentration and cell abundance, determined with epifluorescence and inverted microscopy. Results show that the experimental duration significantly affected net growth rates, independently of volume, with decreasing net growth rates with time. Regarding volume, we found significant, but weak, differences in net growth rates, and significant two-way interactions only for the larger-sized cells. No significant differences in net growth rates across the different volumes were detected for the smaller, most abundant taxa and for the whole assemblage. We conclude that duration, not volume, is the main factor to consider in microcosm experiments, and it should allow the measurement of responses during the exponential growth phase, which can be detected through daily sampling throughout the duration of the experiment. [ABSTRACT FROM AUTHOR]

The role of native predators in controlling or facilitating non-indigenous species (NIS) growing in a fouling assemblage was investigated with a 70-day caging experiment in a marina inside the Gulf of La Spezia (Italy). Submerged PVC panels were divided into three experimental treatment levels: "control panels", "open-caged panels" and "caged panels", to assess the predation effect on the fouling assemblages growing on the panels. Predation effect was observed for two investigated variables. The Shannon Index was significantly higher in caged panels in comparison with controls, while an opposite trend was observed for the coverage area of native species. When testing single NIS abundance, both facilitation and limitation of individual NIS settlement has been observed. Mean coverage of the sabellid Branchiomma luctuosum was significantly higher in caged than in uncaged or open-caged panels, while the ascidian Styela plicata was prevalent in open-caged panels. In general, a predation effect was observed when considering the whole fouling assemblage, including different trends in NIS coverage among treatment levels. The results of this first attempt performed in the Mediterranean Sea encourage further experiments to investigate the biotic resistance provided by native predators against NIS. [ABSTRACT FROM AUTHOR]

Animal behaviors are often modified in urban settings due to changes in species assemblages and interactions. The ability of prey to respond to a predator is a critical behavior, but urban populations may experience altered predation pressure, food supplementation, and other human‐mediated disturbances that modify their responsiveness to predation risk and promote habituation.Citizen‐science programs generally focus on the collection and analysis of observational data (e.g., bird checklists), but there has been increasing interest in the engagement of citizen scientists for ecological experimentation.Our goal was to implement a behavioral experiment in which citizen scientists recorded antipredator behaviors in wild birds occupying urban areas. In North America, increasing populations of Accipiter hawks have colonized suburban and urban areas and regularly prey upon birds that frequent backyard bird feeders. This scenario, of an increasingly common avian predator hunting birds near human dwellings, offers a unique opportunity to characterize antipredator behaviors within urban passerines.For two winters, we engaged citizen scientists in Chicago, IL, USA to deploy a playback experiment and record antipredator behaviors in backyard birds. If backyard birds maintained their antipredator behaviors, we hypothesized that birds would decrease foraging behaviors and increase vigilance in response to a predator cue (hawk playback) but that these responses would be mediated by flock size, presence of sentinel species, body size, tree cover, and amount of surrounding urban area.Using a randomized control–treatment design, citizen scientists at 15 sites recorded behaviors from 3891 individual birds representing 22 species. Birds were more vigilant and foraged less during the playback of a hawk call, and these responses were strongest for individuals within larger flocks and weakest in larger‐bodied birds. We did not find effects of sentinel species, tree cover, or urbanization.By deploying a behavioral experiment, we found that backyard birds inhabiting urban landscapes largely maintained antipredator behaviors of increased vigilance and decreased foraging in response to predator cues. Experimentation in citizen science poses challenges (e.g., observation bias, sample size limitations, and reduced complexity in protocol design), but unlike programs focused solely on observational data, experimentation allows researchers to disentangle the complex factors underlying animal behavior and species interactions. [ABSTRACT FROM AUTHOR]

Simple Summary: This study was based on the determination of podocyst excystment, start time of strobilation, duration of strobilation, and cumulative ephyra numbers of the edible jellyfish Rhopilema esculentum (Kishinouye, 1891) podocysts which were preserved at 2 ± 1 °C for more than 12 months. To this end, the podocysts were tested under nine combinations of three variable temperatures (simulated temperatures increasing from different starting dates of 14.5 °C on 1 April, 18 °C on 1 May, and 23.2 °C on 1 July respectively to natural levels) and three salinities (20, 25, and 30). Podocyst excystment and ephyrae production occurred in all treatments. Higher temperature and lower salinity significantly facilitated the podocyst excystment and accelerated the start time of strobilation (p < 0.05). Significantly greater ephyra numbers were produced with lower salinity (20 and 25) and temperatures increasing from 18 °C on 1 May to natural levels (p < 0.05). As one of the edible jellyfish species, Rhopilema esculentum (Kishinouye, 1891) is a traditional fishery resource and an important economic aquaculture species in China. However, facing the current situation of natural resources exhaustion and problems of breeding population frequent disease, quantity, and quality of seedlings in artificial breeding cannot satisfy the market demand. Temperature and salinity have been considered to play crucial roles in regulating R. esculentum asexual reproduction. This study examined the combined effects by exposing post-preserved R. esculentum podocysts (preserved at 2 ± 1 °C for more than 12 months) to three variable temperatures (simulated temperatures increasing from different starting dates of 14.5 °C on 1 April, 18 °C on 1 May, and 23.2 °C on 1 July, respective to natural levels) and three salinities (20, 25, and 30). Podocyst excystment, the start time of strobilation, duration of strobilation, and cumulative ephyra numbers were tested for 45 days and transfer rates from podocysts to ephyrae were analyzed to assess the most optimal combination of temperature and salinity. The results showed that podocyst excystment and ephyrae production occurred in all treatments. Higher temperature and lower salinity significantly facilitated the podocyst excystment and accelerated the start time of strobilation (p < 0.05). Significantly greater ephyra numbers were produced with lower salinity (20 and 25) and temperatures increasing from 18 °C on 1 May to natural levels (p < 0.05). There were significant interactions between temperature and salinity on the cumulative ephyra numbers and transfer rates from podocysts to ephyrae (p < 0.05). These results suggested that R. esculentum podocysts for long-term preservation at low temperature could be recycled. Temperature and salinity regulation can affect the number and time of R. esculentum seedlings to achieve high production and satisfy the market demand for real-time seedling supply. This conclusion would provide a scientific basis for the innovative methods of sustainable utilization of the edible jellyfish (R. esculentum) resources. [ABSTRACT FROM AUTHOR]

Whether and how adaptive evolution adjusts the breadth of adaptation in coordination with the genome are essential issues for connecting evolution with ecology. To address these questions, experimental evolution in five Escherichia coli strains carrying either the wild-type genome or a reduced genome was performed in a defined minimal medium (C0). The ancestral and evolved populations were subsequently subjected to fitness and chemical niche analyses across an environmental gradient with 29 combinations of eight chemical components of the minimal medium. The results showed that adaptation was achieved not only specific to the evolutionary condition (C0), but also generally, to the environmental gradient; that is, the breadth of adaptation to the eight chemical niches was expanded. The magnitudes of the adaptive improvement and the breadth increase were both correlated with genome reduction and were highly significant in two out of eight niches (i.e., glucose and sulfate). The direct adaptation-induced correlated adaptation to the environmental gradient was determined by only a few genome mutations. An additive increase in fitness associated with the stepwise fixation of mutations was consistently observed in the reduced genomes. In summary, this preliminary survey demonstrated that evolution finely tuned the breadth of adaptation correlated with genome reduction. [ABSTRACT FROM AUTHOR]

The growth rate of the first lower molar and its wear features have been studied in narrow-skulled vole individuals (n = 39) that received hard and soft feeds under laboratory conditions. Using tetracycline markers, we have found that the tooth height increases by 0.33–0.56 mm throughout the day. Voles that received soft feed, in general, had a lower rate of molar growth, a lower crown, and a more obtuse wear angle of the chewing surface than the animals feeding on hard feed; they were also characterized by the appearance of lateral wear facets. As these signs of wear developed in animals fed soft food, the growth rate of the molar increased. [ABSTRACT FROM AUTHOR]

Invasive species threaten the conservation of marine environments, and urgent management strategies are needed to prevent their introduction, establishment and spread. Specifically, marine invasive predators destabilize ecological interactions and alter community structure and function. However, most of the evidence showing the effect of these predators is restricted to a few species and regions, while for others the information remains scarce.This study experimentally evaluated the ecological effects of the sea slug Pleurobranchaea maculata, a recently introduced invasive predator, on the fouling communities of a cold‐temperate port in the South‐western Atlantic.The results show that increasing predation pressure reduces significantly the abundance of sea anemones, which are among the preferred prey items.This study reveals new evidence to help better understand the effects of P. maculata on the biological communities of a recently invaded region. Furthermore, it provides the first experimental evidence supporting the hypothesis that marine invasive predators can induce a significant decrease in the abundance of native species in benthic communities of cold‐temperate marine environments in the South‐western Atlantic. [ABSTRACT FROM AUTHOR]

The functional roles of freshwater mussels (Unionida) in tropical systems are poorly understood. We quantified the effects of mussel filtration, excretion and deposition in three anthropogenic tropical systems, i.e. a man-made lake, abandoned mining pool and rice paddy channel. Sinanodonta cf. woodiana (non-native) was present at all three sites, whilst Pilsbryoconcha compressa (native) was present in the channel only. Clearance rates, biodeposition rates and effects on suspended algal pigment and dissolved nutrient concentrations were quantified in controlled, replicated experiments in laboratory tanks with water from original habitats. Clearance rates were generally low and did not explain the high biodeposition rates observed. A considerable proportion of the natural diet of these populations may therefore consist of material that was not available in tanks, i.e. benthic or deposited algae. Deposition rates in lake and channel populations exceeded published rates from temperate and Mediterranean habitats, presumably due to prevalence of non-palatable material and/or higher metabolic rates in tropical systems. The presence of S. cf. woodiana but not P. compressa led to a strong increase in total ammonia nitrogen concentrations and N:P ratios, exceeding estimations from other systems. This study suggests that freshwater mussels play different functional roles in anthropogenic tropical habitats than in temperate systems. [ABSTRACT FROM AUTHOR]

Background: Geographically separated population growth of microbes is a common phenomenon in microbial ecology. Colonies are representative of the morphological characteristics of this structured population growth. Pattern formation by single colonies has been intensively studied, whereas the spatial distribution of colonies is poorly investigated. Results: The present study describes a first trial to address the questions of whether and how the spatial distribution of colonies determines the final colony size using the model microorganism Escherichia coli, colonies of which can be grown under well-controlled laboratory conditions. A computational tool for image processing was developed to evaluate colony density, colony size and size variation, and the Voronoi diagram was applied for spatial analysis of colonies with identical space resources. A positive correlation between the final colony size and the Voronoi area was commonly identified, independent of genomic and nutritional differences, which disturbed the colony size and size variation. Conclusions: This novel finding of a universal correlation between the spatial distribution and colony size not only indicated the fair distribution of spatial resources for monogenetic colonies growing with identical space resources but also indicated that the initial localization of the microbial colonies decided by chance determined the fate of the subsequent population growth. This study provides a valuable example for quantitative analysis of the complex microbial ecosystems by means of experimental ecology. [ABSTRACT FROM AUTHOR]

Transplant studies have long been a cornerstone of experimental ecology. Lichens and bryophytes have several useful characteristics for transplantation: they are small, easily transported, and highly responsive to environmental gradients. Here we conduct a systematic review to synthesise lichen and bryophyte transplant studies up until March 2020 (N=454). A great majority of studies (67%) used lichen and bryophyte transplants as biosensors of airborne pollutants. Other research themes such as forest management and biotic interactions were associated with comparably modest bodies of work. A total of 247 lichen and bryophyte species had been used in transplant studies, but four species predominated: Hypogymnia physodes, Pseudevernia furfuracea, Evernia prunastri and Lobaria pulmonaria. Liverworts were only transplanted in 4% of studies, and most studies focused on epiphytic (69%) or terricolous species (31%). A small group of studies (N=15) used whole-community transplants with areas ranging from 25–250,000 cm2. Apart from pollution research, studies centered on assisted colonization and simulated climate change appear to be increasing most rapidly in time. There were several recurrent lines of investigation within the included literature (e.g., edge effects, colonization of young forests, climate change effects and local adaptation) and we synthesise the key results. We recommend that future research address underrepresented taxa (e.g., liverworts, biological soil crusts) and geographic gaps, namely Australia and Africa. [ABSTRACT FROM AUTHOR]

A key research aim for lotic ecosystems is the identification of natural and anthropogenic pressures that impact ecosystem status and functions. As a consequence of these perturbations, many lotic ecosystems are exposed to complex combinations of nonchemical and chemical stressors. These stressors comprise temperature fluctuations, flow alterations, elevated solute loads or xenobiotics, and all these factors can pose stress upon aquatic ecosystems on different temporal, spatial and biological scales. Factorial experiments are essential to reveal causal relationships especially between combined stressors and their effects in the environment. However, experimental tools that account for the complexity of running waters across different ecosystem compartments, levels of biological organisation, natural or anthropogenic environmental gradients, and replicability are rare. Here we present a new research infrastructure consisting of streamside mobile mesocosms (MOBICOS) that allows analysing the effects of stressors and stressor combinations through multifactorial experiments in near‐natural settings and across anthropogenic pressure gradients. Consisting of eight container‐based running water laboratories operated as bypasses to running surface waters, MOBICOS combines in situ real‐time monitoring of physicochemical and biological parameters with manipulative experiments across ranges of environmental conditions. Different flume types can be set up within MOBICOS to separate and combine different ecosystem compartments (pelagic, epibenthic and hyporheic zones) in a flexible and modular way. Due to its compact design, the MOBICOS units can be shifted easily to particular sites of interest. Furthermore, simultaneous operation of multiple MOBICOS units at different sites allows the integration of natural gradients in multifactorial experiments. We highlight the versatility of the MOBICOS experimental infrastructure with two case studies addressing (a) hydraulic control of lotic biofilms and (b) pollution‐induced community tolerance of biofilms along an environmental gradient. The modular and mobile MOBICOS units have the potential to significantly advance our understanding of causal relationships between natural environmental oscillations, anthropogenic stressors and their combined ecological impacts on lotic aquatic ecosystems beyond existing stream mesocosm approaches. [ABSTRACT FROM AUTHOR]

Coexistence usually are exceeding the explicable rate by competitive exclusion principle. Since the pioneer Gause, many studies have used protist microcosm systems to study competitive exclusion. We explored a two-species system with the testate-amoebae: (Arcella intermedia and Pyxidicula operculata), where competitive exclusion is expected to occur. We determined their growth curves individually and under competitive interaction. We used a state-space model to represent system dynamics and calculated posterior population sizes simulating competition dynamics. Contrarily to our expectation, Arcella and Pyxidicula showed similar growth rates (1.37 and 1.46 days-1 respectively) and only different carrying capacity (1,997 and 25,108 cells cm-2 respectively). The maximum number of cells of both species when growing in competition was much lower if compared to the monospecific cultures (in average, 73% and 80% less for Arcella and Pyxidicula respectively). However, our competition experiments always resulted in coexistence. According to the models, the drop in growth rates and stochasticity mainly explains our coexistence results. We propose that a context of ephemeral resources can explain these results. Additionally, we propose generating factors of stochasticity as intraspecific variation, small population effects, toxicity of waste products and influence of the bacterial community. [ABSTRACT FROM AUTHOR]

The seeds of most plant species are dispersed by multiple mechanisms. Whether functional traits mediate positive correlations or negative correlations (trade-offs) between different dispersal mechanisms has important consequences for ecological and evolutionary dynamics. We investigate how traits affect wind-driven seed dispersal through the air and across the ground (primary and secondary wind dispersal, respectively). We hypothesized that primary and secondary wind dispersal were positively correlated because they should both decrease with the wing loading of seeds. We test this hypothesis with wind-tunnel experiments using different seed morphologies of Zygophyllum xanthoxylon (heterocarpous) and Calligonum species. We measured primary dispersal distance at varying wind speeds and release heights, and quantified secondary dispersal potential as the threshold wind speed for seed movement on four ground surfaces. Contrary to our expectation, we found a context-dependent trade-off between primary and secondary wind dispersal. The smoother the ground surface, the stronger this trade-off becomes. The trade-off results from a positive relationship between wing loading and the ratio of vertical to horizontal seed projection (v/h-ratio): an increasing v/h-ratio not only promotes secondary dispersal on smooth surfaces by increasing wind interception of seeds, but also decreases primary dispersal distance by increasing wing loading and terminal velocity of seeds. The trade-off contradicts the widespread assumption of a positive correlation between primary and secondary dispersal. A simple classification into poorly and well-dispersed seeds is thus not possible. The trade-off may affect dynamics of succession and the expansion of pioneer vegetation, while potentially slowing down evolutionary responses to selection on seed dispersal. [ABSTRACT FROM AUTHOR]

Willow floodplain plantations have been proposed as part of plans to create tidal wetlands for ecosystem‐based flooding defence of estuaries. Forests characterised by willows (genus Salix) are found in riparian floodplains in Europe up to the river mouth, e.g. up to tidal wetlands along the Scheldt and Elbe. However, sea level rise accompanied by accelerated tidal flooding and salt‐water intrusion may limit the effectiveness of willows for flooding defence of floodplains located at estuaries near their junction with the sea.We studied juvenile floodplain willows (Salix alba and Salix viminalis) in a mesocosm experiment with a combined tidal flooding and salinity treatment in a climate chamber. Permanent and semi‐permanent flooding of roots and periodic flooding of shoots reduced shoot length, shoot biomass, bending capacity, and breaking resistance. However, partial submergence did not affect shoot morphology or biomechanical traits. In S. viminalis, shoot diameter was generally larger compared to S. alba and this larger diameter resulted in a higher maximum breaking force. However, S. alba showed more consistent results in diameter size with lower variation than S. viminalis. The applied salinity treatments of up to 2 parts per thousand did not have significant effects on willow shoot morphology or biomechanical traits.We conclude that juveniles of both willow species are resilient to periodic tidal flooding and salinity values of up to 2 parts per thousand with respect to shoot traits. However, the reduction in shoot growth and biomechanical properties with permanent flooding suggests that juvenile willow establishment will be sensitive to sea level rise and increased flooding, and will result in changes in the vegetation of tidal freshwater wetlands. Salix alba and S. viminalis may serve in innovative capacities as supplementary features for estuarine flooding defence in tidal wetlands and tools for ecological restoration at appropriate sites. However, studies addressing whole ecosystems at a large scale are recommended before using S. alba and S. viminalis in floodplain plantations to protect river estuaries. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Applied Ecology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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A fundamental challenge in experimental ecology is to capture nonlinearities of ecological responses to interacting environmental drivers. Here, we demonstrate that gradient designs outperform replicated designs for detecting and quantifying nonlinear responses. We report the results of (1) multiple computer simulations and (2) two purpose‐designed empirical experiments. The findings consistently revealed that unreplicated sampling at a maximum number of sampling locations maximised prediction success (i.e. the R² to the known truth) irrespective of the amount of stochasticity and the underlying response surfaces, including combinations of two linear, unimodal or saturating drivers. For the two empirical experiments, the same pattern was found, with gradient designs outperforming replicated designs in revealing the response surfaces of underlying drivers. Our findings suggest that a move to gradient designs in ecological experiments could be a major step towards unravelling underlying response patterns to continuous and interacting environmental drivers in a feasible and statistically powerful way. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article offers information on the use of sensor networks in experimental ecology. Topics discussed include development and use of sensors in ecological field research; monitoring and comparing ecological systems within the National Ecological Observatory Network; and use of carbon dioxide sensors for high temporal resolution measurement of soil respiration in the Monsoon Rainfall Manipulation Experiment.

Microfluidics is an emerging technology that is used more and more in biology experiments. Its capabilities of creating precisely controlled conditions in cellular dimensions make it ideal to explore cell-cell and cell-environment interactions. Thus, a wide spectrum of problems in microbial ecology can be studied using engineered microbial habitats. Moreover, artificial microfluidic ecosystems can serve as model systems to test ecology theories and principles that apply on a higher level in the hierarchy of biological organization. In this mini review we aim to demonstrate the versatility of microfluidics and the diversity of its applications that help the advance of microbiology, and in more general, experimental ecology. [ABSTRACT FROM AUTHOR]

Change makers are visionaries who wish to bring change to their respective fields. As technological change is accelerating, it is relevant to consider, how the way and what we teach can evolve with the future to remain meaningful and pioneering. Design Factory at Aalto University, as an innovative experimental ecosystem with interdisciplinary principles and new teaching methodologies has been successful in and at the forefront in educating the students to be change-makers. The paper presents a case study of holistically anticipating plausible futures for innovative experimental ecosystems utilizing a foresight approach. We analyze how the ways of working, spaces, and teaching methods of one such ecosystem, Design Factory at Aalto University in Finland, could support students learning in the year 20 × 6 {x = 2, 3}. We present the process of drawing virtual lines that connect trends, future drivers, visions, and scenarios using a contemporary approach that fuses qualitative and quantitative methods. The results from the study are six future scenarios for the Design Factory, that have implications for innovation ecosystems in general. These results are expected to further foster or trigger new research and development experiments, directions for building radical environments, new teaching methods and ways of working. [ABSTRACT FROM AUTHOR]

Deciphering the ecology of marine obligate hydrocarbonoclastic bacteria (MOHCB) is of crucial importance for understanding their success in occupying distinct niches in hydrocarbon-contaminated marine environments after oil spills. In marine coastal sediments, MOHCB are particularly subjected to extreme fluctuating conditions due to redox oscillations several times a day as a result of mechanical (tide, waves and currents) and biological (bioturbation) reworking of the sediment. The adaptation of MOHCB to the redox oscillations was investigated by an experimental ecology approach, subjecting a hydrocarbon-degrading microbial community to contrasting oxygenation regimes including permanent anoxic conditions, anoxic/oxic oscillations and permanent oxic conditions. The most ubiquitous MOHCB, Alcanivorax and Cycloclasticus, showed different behaviors, especially under anoxic/oxic oscillation conditions, which were more favorable for Alcanivorax than for Cycloclasticus. The micro-diversity of 16S rRNA gene transcripts from these genera revealed specific ecotypes for different oxygenation conditions and their dynamics. It is likely that such ecotypes allow the colonization of distinct ecological niches that may explain the success of Alcanivorax and Cycloclasticus in hydrocarbon-contaminated coastal sediments during oil-spills. [ABSTRACT FROM AUTHOR]

Young-of-year (YOY) fishes are sometimes numerically dominant vertebrate consumers in many large river systems, but their effects as predators are not as well understood as those of adult fishes. We predicted that YOY fishes influence community composition and abundance of invertebrate prey. Predation effects could be especially important in recruitment-driven dryland river systems, where YOY fishes seasonally comprise a large portion of overall fish biomass., We conducted a mesocosm experiment to quantify effects of YOY fishes on trophic dynamics and interactions with environmental factors in a dryland river food web. We manipulated presence of YOY fishes (an assemblage of cypriniform species) and supplemental allochthonous carbon (LEAF treatments) in 24 mesocosms, and measured invertebrate abundance and diversity over 6 weeks. Experimental conditions mimicked a seasonal river drying regime that occurs during YOY fish growth. Seasonal drying in the Rio Grande frequently results in isolated pools with altered habitat complexity and riparian connectivity., Fishes exerted direct top-down control of invertebrate assemblage composition through differential prey selection, and indirect control mediated by non-lethal responses of invertebrates to predatory fishes. We observed enhanced water clarity in LEAF treatments associated with greater prey selectivity in fishes, presumably through enhanced visual feeding. Stable isotope analysis (C and N) was used to measure indirect impacts of YOY fishes on invertebrate prey items. YOY fishes caused a significant decrease in 'isotopic niche breadth' among invertebrate taxa, suggesting that fish predators limit foraging opportunities for these consumers. However, allochthonous carbon sources were predominant in invertebrate diets in all LEAF treatments, suggesting consumer access to more biologically available autochthonous production is limited by factors other than fish predation., Although the roles of abiotic drivers and adult fishes in determining food web structure have received more attention, our results indicate that YOY fishes exert biologically relevant top-down control of invertebrate assemblage composition and trophic complexity in dryland river ecosystems against a backdrop of substantial changes in carbon availability and abiotic conditions (e.g. water quality and habitat volume) over the growing season. [ABSTRACT FROM AUTHOR]

The cascading effect of predators on the functioning of adjacent ecosystems can occur when the life cycles of their prey include two ecosystems. However, there has been little consideration of which habitat attributes can modify the strength of these cross-ecosystem trophic cascades. Habitat size can mediate the strength of predator-prey interactions, and thus affect within-ecosystem trophic cascades. We hypothesise that similar effects of habitat size might affect cross-ecosystem trophic cascades., It has been shown that terrestrial predators (e.g. spiders) can capture terrestrial adult insects as they attempt to oviposit in the waters of bromeliads. Such terrestrial predators could therefore alter the trophic structure and functioning of the aquatic food web. If spiders affect an aquatic trophic level that is influenced by bromeliad size, then the strength of the cross-ecosystem trophic cascade will also depend on bromeliad size., To test this general hypothesis, we manipulated the presence of a funnel-web spider ( Aglaoctenus castaneus, Lycosidae), which builds a single web over water-filled bromeliads, in bromeliads differing in size and examined effects on the aquatic invertebrate community and on ecosystem functions (decomposition, detrital nitrogen flux)., The effects of spiders were largely independent of bromeliad size. Spiders did initiate changes in the trophic structure of aquatic food webs, reducing the biomass of predators, especially damselflies and dytiscid beetles. Spiders also increased decomposition despite having no effect on detritivore biomass or composition., These results are most parsimoniously explained by (i) a behaviourally mediated trophic cascade, whereby damselfly adults avoid bromeliads with spiders, and aquatic detritivores increase rates of detrital processing in the absence of damselfly larvae, and (ii) stimulation of decomposition through nutrients added from spider faeces and prey carcasses. We believe that this is the first study to show that terrestrial predators can affect decomposition by reducing the flux of keystone aquatic predators with complex life cycles. [ABSTRACT FROM AUTHOR]

Physical disturbances and resource pulses are major structuring drivers of terrestrial and aquatic ecosystems. The accumulations of exported dead leaves from the Neptune grass, Posidonia oceanica (L.) Delile are ephemeral and highly dynamic detrital habitats offering food sources and shelter for vagile macrofauna community. These habitats are frequently subject to wind and storms which can add "new" detrital material to previous accumulations; these can be defined as resource pulses and could potentially impact the associated macrofauna. This study assesses the impact of an experimental resource pulse on the macrofauna associated with exported P. oceanica litter accumulations. The experimental design consisted of two pulse treatments (the addition of dead leaves with and without the associated fauna), and two controls (one procedural, and one total control), where the added material was left underwater for 14 days. Invertebrates then present in the sampled detritus were all identified and counted. Our data suggest that the responses of these invertebrates to resource pulses present intermediate characteristics between aquatic and terrestrial ecosystems responses. Inputting a moderate amount of dead P. oceanica leaves into experimental mesocosms had a non-negligible impact and rapidly affected the macrofauna community. Specialist detritivores species were boosted while herbivore/detritivore species dramatically decreased. Predators also showed a modest but significant density increase, demonstrating the fast propagation of the pulse response throughout the entire community and through several trophic levels. Strict hypoxia-tolerant species were also only observed in the treated mesocosms, indicating the strong influence of resource pulses on physico-chemical conditions occurring inside litter accumulations. [ABSTRACT FROM AUTHOR]

Methodological approaches to the description of variants and degrees of hypselodont tooth mesowear in voles are proposed on the basis of studies on the collection of skulls of two vole species trapped in the field (narrow-headed vole, n = 38; common vole, n = 22) and two species from laboratory colonies (narrow-headed vole, n = 46; root vole, n = 76). Trends in the manifestation of different mesowear variants have been analyzed in experiments on feeding root voles from the laboratory colony with 'hard' and 'soft' foods. It has been found that animals kept on low-abrasive diet show signs of wear due to tooth-to-tooth contact, such as low crown height, relatively obtuse wear angle and more upright position of m/1 in the jaw, shallow occlusal surface relief, and lateral wear facets. Chewing hard food items requires application of vertical occlusal pressure, which result in the formation of a depression in repair dentin, while denser dentin at the anterior enamel wall of prisms remains unworn. [ABSTRACT FROM AUTHOR]

The origin of new and complex structures and functions is fundamental for shaping the diversity of life. Such key innovations are rare because they require multiple interacting changes.We sought to understand howthe adaptive landscape led to an innovation whereby bacteriophage l evolved the newability to exploit a receptor, OmpF, on Escherichia coli cells. Previous work showed that this ability evolved repeatedly, despite requiring four mutations in one virus gene. Here, we examine how this innovation evolved by studying six intermediate genotypes of l isolated during independent transitions to exploit OmpF and comparing them to their ancestor. All six intermediates showed large increases in their adsorption rates on the ancestral host. Improvements in adsorption were offset, in large part, by the evolution of host resistance, which occurred by reduced expression of LamB, the usual receptor for l. As a consequence of host coevolution, the adaptive landscape of the virus changed such that selection favouring four of the six virus intermediates became stronger after the host evolved resistance, thereby accelerating virus populations along the path to using the new OmpF receptor. This dependency of viral fitness on host genotype thus shows an important role for coevolution in the origin of the new viral function. [ABSTRACT FROM AUTHOR]

Since its emergence in 1998, positive psychology has flourished. Among its successes is the burgeoning field of applied positive psychology (APP), involving interventions to promote wellbeing. However, the remit of APP is currently unclear. As such, we offer a meta-theoretical conceptual map delineating the terrain that APP might conceivably cover, namely, the Layered Integrated Framework Example model. The model is based on Wilber's (J Conscious Stud 4(1):71-92, ) Integral Framework, which features the four main ontological 'dimensions' of the person. We then stratify these dimensions to produce a comprehensive conceptual map of the person, and of the potential areas of application for APP. For example, we deconstruct the collective dimensions of Wilber's framework using the levels of Bronfenbrenner's (Am Psychol 32(7):513-531, ) experimental ecology. The result is a detailed multidimensional framework which facilitates a comprehensive approach to promoting wellbeing, and which charts a way forward for APP. [ABSTRACT FROM AUTHOR]

Disease ecologists and wildlife managers are increasingly interested in understanding how predators regulate infection in prey populations. The healthy herds hypothesis suggests that predators may decrease infection prevalence by decreasing overall population size, reducing density-dependent transmission and culling infected individuals from a population. While this model incorporates density-mediated indirect interactions ( DMIIs), it does not incorporate the potential role of trait-mediated indirect interactions ( TMIIs)., Using wood frog tadpoles ( Lithobates sylvatica), we examined whether predator cues could alter the prevalence and intensity of infection by the fungal pathogen Batrachochytrium dendrobatidis [Bd] and whether both stressors could alter the host's life history traits., Exposure to predator cues caused tadpoles to have reduced Bd infection loads, potentially as a result of stress-induced immunoenhancement. Tadpoles exposed to Bd had faster development than tadpoles not exposed to Bd, but they did not differ in survival or growth., This suggests that, in this life stage of this species, Bd infection does not have fitness costs. These data suggest that the trait-mediated effects of predators on infection may alter epidemiological outcomes of Bd exposure. [ABSTRACT FROM AUTHOR]

Laboratory microcosm experiments using protists as model organisms have a long tradition and are widely used to investigate general concepts in population biology, community ecology and evolutionary biology. Many variables of interest are measured in order to study processes and patterns at different spatiotemporal scales and across all levels of biological organization. This includes measurements of body size, mobility or abundance, in order to understand population dynamics, dispersal behaviour and ecosystem processes. Also, a variety of manipulations are employed, such as temperature changes or varying connectivity in spatial microcosm networks., Past studies, however, have used varying methods for maintenance, measurement, and manipulation, which hinders across-study comparisons and meta-analyses, and the added value they bring. Furthermore, application of techniques such as flow cytometry, image and video analyses, and in situ environmental probes provide novel and improved opportunities to quantify variables of interest at unprecedented precision and temporal resolution., Here, we take the first step towards a standardization of well-established and novel methods and techniques within the field of protist microcosm experiments. We provide a comprehensive overview of maintenance, measurement and manipulation methods. An extensive supplement contains detailed protocols of all methods, and these protocols also exist in a community updateable online repository., We envision that such a synthesis and standardization of methods will overcome shortcomings and challenges faced by past studies and also promote activities such as meta-analyses and distributed experiments conducted simultaneously across many different laboratories at a global scale. [ABSTRACT FROM AUTHOR]

A series of 14 day experiments was conducted on five common New Zealand fish species (redfin bully Gobiomorphus huttoni, inanga Galaxias maculatus, brown trout Salmo trutta, longfin eel Anguilla dieffenbachii and koaro Galaxias brevipinnis) to assess the effect of pH on survival and changes in body mass. No species survived in water of pH <4 although there was 100% survival of all adults at pH 4·5, G. maculatus larvae were also tested and had high mortality at this pH. Results suggest that adults are tolerant of low- pH waters; however, successful remediation of anthropogenically acidified streams will require an understanding of the susceptibility to low pH on different life cycle stages. [ABSTRACT FROM AUTHOR]

An important characteristic of many wetland plants in semi-arid regions is their capacity to withstand fluctuations between extended dry phases and floods. However, anthropogenic river regulation can reduce natural flow variability in riverine wetlands, causing a decline in the frequency and duration of deep flooding as well as extended droughts, and an increase in shallow flooding and soil saturation. Our aim in this paper was to use an experimental approach to examine whether reductions in flooding and drought disadvantage species adapted to both these extremes, and favours those with water requirements that match the new regime of frequent low-level flooding. We compared the growth characteristics and biomass allocation of three native Australian aquatic macrophytes ( Pseudoraphis spinescens, Juncus ingens and Typha domingensis), which co-occur at Barmah Forest, south-eastern Australia, under three water treatments: drought, soil saturation and deep flooding. The responses of species to the treatments largely reflected changes in their relative abundance at Barmah Forest since river regulation. Typha domingensis, which has remained uncommon, performed relatively poorly in all treatments, while J. ingens, which has increased its range, exhibited more vigorous growth under soil saturation. Pseudoraphis spinescens, which was once widespread but has declined markedly in its distribution, grew strongly under all water treatments. These findings suggest that a return to more natural, variable river flow regimes can potentially be an important conservation and restoration strategy in ecosystems characterised by species that have adaptations to extreme hydrological growing conditions. [ABSTRACT FROM AUTHOR]

One of the most important defensive host traits against brood parasitism is the detection and ejection of parasitic eggs from their nests. Here, we explore the possible role of olfaction in this defensive behaviour. We performed egg-recognition tests in magpie Pica pica nests with model eggs resembling those of parasitic great spotted cuckoos Clamator glandarius. In one of the experiment, experimental model eggs were exposed to strong or moderate smell of tobacco smoke, whereas those of a third group (control) were cleaned with disinfecting wipes and kept in boxes containing odourless cotton. Results showed that model eggs with strong tobacco scent were more frequently ejected compared with control ones. In another experiment, models were smeared with scents from cloacal wash from magpies (control), cloacal wash or uropygial secretions from cuckoos, or human scents. This experiment resulted in a statistically significant effect of treatment in unparasitized magpie nests in which control model eggs handled by humans were more often rejected. These results provide the first evidence that hosts of brood parasites use their olfactory ability to detect and eject foreign eggs from their nests. These findings may have important consequences for handling procedures of experimental eggs used in egg-recognition tests, in addition to our understanding of interactions between brood parasites and their hosts. [ABSTRACT FROM AUTHOR]

The release of antibiotics (AB) into the environment poses several threats for human health due to potential development of AB-resistant natural bacteria. Even though the use of low-dose antibiotics has been promoted in health care and farming, significant amounts of AB are observed in aquatic environments. Knowledge on the impact of AB on natural bacterial communities is missing both in terms of spread and evolution of resistance mechanisms, and of modifications of community composition and productivity. New approaches are required to study the response of microbial communities rather than individual resistance genes. In this study a chemostat-based experiment with 4 coexisting bacterial strains has been performed to mimicking the response of a freshwater bacterial community to the presence of antibiotics in low and high doses. Bacterial abundance rapidly decreased by 75% in the presence of AB, independently of their concentration, and remained constant until the end of the experiment. The bacterial community was mainly dominated by Aeromonas hydrophila and Brevundimonas intermedia while the other two strains, Micrococcus luteus and Rhodococcus sp. never exceed 10%. Interestingly, the bacterial strains, which were isolated at the end of the experiment, were not ABresistant, while reassembled communities composed of the 4 strains, isolated from treatments under AB stress, significantly raised their performance (growth rate, abundance) in the presence of AB compared to the communities reassembled with strains isolated from the treatment without AB. By investigating the phenotypic adaptations of the communities subjected to the different treatments, we found that the presence of AB significantly increased co-aggregation by 5-6 fold. These results represent the first observation of co-aggregation as a successful strategy of AB resistance based on phenotype in aquatic bacterial communities, and can represent a fundamental step in the understanding of the effects of AB in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Early generations of hybrids can express both genetic incompatibilities and phenotypic novelty. Insights into whether these conflicting interactions between intrinsic and extrinsic selection persist after a few generations of recombination require experimental studies. To address this question, we use interpopulation crosses and recombinant inbred lines (RILs) of the copepod Tigriopus californicus, and focus on two traits that are relevant for the diversification of this species: survivorship during development and tolerance to thermal stress. Experimental crosses between two population pairs show that most RILs between two heat-tolerant populations show enhanced tolerance to temperatures that are lethal to the respective parentals, whereas RILs between a heat-tolerant and a heat-sensitive population are intermediate. Although interpopulation crosses are affected by intrinsic selection at early generational hybrids, most of the sampled F9 RILs have recovered fitness to the level of their parentals. Together, these results suggest that a few generations of recombination allows for an independent segregation of the genes underlying thermal tolerance and cytonuclear incompatibilities, permitting certain recombinant lineages to survive in niches previously unused by parental taxa (i.e., warmer thermal environments) without incurring intrinsic selection. [ABSTRACT FROM AUTHOR]

Background and Aims Plant genotypic mixtures have the potential to increase yield stability in variable, often unpredictable environments, yet knowledge of the specific mechanisms underlying enhanced yield stability remains limited. Field studies are constrained by environmental conditions which cannot be fully controlled and thus reproduced. A suitable model system would allow reproducible experiments on processes operating within crop genetic mixtures. Methods Phenotypically dissimilar genotypes of Arabidopsis thaliana were grown in monocultures and mixtures under high levels of competition for abiotic resources. Seed production, flowering time and rosette size were recorded. Key Results Mixtures achieved high yield stability across environments through compensatory interactions. Compensation was greatest when plants were under high levels of heat and nutrient stress. Competitive ability and mixture performance were predictable from above-ground phenotypic traits even though below-ground competition appeared to be more intense. Conclusions This study indicates that the mixing ability of plant genotypes can be predicted from their phenotypes expressed in a range of relevant environments, and implies that a phenotypic screen of genotypes could improve the selection of suitable components of genotypic mixtures in agriculture intended to be resilient to environmental stress. [ABSTRACT FROM PUBLISHER]

The article discusses the integration of designed experiments into urban planning. Topics include the uncertainty and gaps in scientific knowledge within large-scale urban sustainability and green infrastructure projects, an approach in experimental ecology, called adaptive management, and an idea by director of the Urban Ecology and Design Laboratory at Yale University, Alexander J. Felson, to incorporate designed experiments into urban design projects.

Understanding how populations and communities respond to competition is a central concern of ecology. A seminal theoretical solution first formalised by Levins (and re-derived in multiple fields) showed that, in theory, the form of a trade-off should determine the outcome of competition. While this has become a central postulate in ecology it has evaded experimental verification, not least because of substantial technical obstacles. We here solve the experimental problems by employing synthetic ecology. We engineer strains of Escherichia coli with fixed resource allocations enabling accurate measurement of trade-off shapes between bacterial survival and multiplication in multiple environments. A mathematical chemostat model predicts different, and experimentally verified, trajectories of gene frequency changes as a function of condition-specific trade-offs. The results support Levins' postulate and demonstrates that otherwise paradoxical alternative outcomes witnessed in subtly different conditions are predictable. [ABSTRACT FROM AUTHOR]

Advances in high-throughput nucleic acid sequencing have improved our understanding of microbial communities in a number of ways. Deeper sequence coverage provides the means to assess diversity at the resolution necessary to recover ecological and biogeographic patterns, and at the same time single-cell genomics provides detailed information about the interactions between members of a microbial community. Given the vastness and complexity of microbial ecosystems, such analyses remain challenging for most environments, so greater insight can also be drawn from analysing less dynamic ecosystems. Here, we outline the advantages of one such environment, the wood-digesting hindgut communities of termites and cockroaches, and how it is a model to examine and compare both protist and bacterial communities. Beyond the analysis of diversity, our understanding of protist community ecology will depend on using statistically sound sampling regimes at biologically relevant scales, transitioning from discovery-based to experimental ecology, incorporating single-cell microbiology and other data sources, and continued development of analytical tools. [ABSTRACT FROM AUTHOR]

Experimental laboratory systems (ELS) are widely applied research tools to test theoretical predictions in ecology and evolution. Combining ELS with automated image analysis could significantly boost information acquisition due to the ease at which abundance and morphological data is collected. Despite the advantages of image analysis, the technology has not been fully adopted yet, presumably due to the difficulties of technical implementation., The tools needed to integrate image analysis in ELS are nowadays readily available: digital camera equipment is purchased at limited costs and free software solutions which allow sophisticated image processing and analysis exist. Here, we give a concise description how to integrate these pieces into a largely automated image analysis workflow. We provide researchers with necessary background information on the principles of image analysis, explaining how to standardize image acquisition and how to validate the results to reduce bias., Three cross-platform and open-source software solutions for image analysis are compared: ImageJ, the EBImage package in R, and Python with the SciPy/scikit image libraries. The relative strengths and limitations of each solution are compared and discussed. In addition, a set of test images and three scripts are provided in the Online Supplementary Material to illustrate the use of image analysis and help biologists to implement image analysis in their own systems., To demonstrate the reliability and versatility of a validated image analysis workflow, we introduce our own Tetrahymena thermophila ELS. Then, examples from evolutionary ecology are provided showing the advantages of image analysis to study different ecological questions, aiming at both the population and individual level., Experimental laboratory systems that integrate the advantages of image analysis extend their application and versatility compared with regular ELS. Such improvements are necessary to understand complex processes such as eco-evolutionary feedbacks, community dynamics and individual behaviour in ELS. [ABSTRACT FROM AUTHOR]

In this paper, the two-sample scale problem is addressed within the rank framework which does not require to specify the underlying continuous distribution. However, since the power of a rank test depends on the underlying distribution, it would be very useful for the researcher to have some information on it in order to use the possibly most suitable test. A two-stage adaptive design is used with adaptive tests where the data from the first stage are used to compute a selector statistic to select the test statistic for stage 2. More precisely, an adaptive scale test due to Hall and Padmanabhan and its components are considered in one-stage and several adaptive and non-adaptive two-stage procedures. A simulation study shows that the two-stage test with the adaptive choice in the second stage and with Liptak combination, when it is not more powerful than the corresponding one-stage test, shows, however, a quite similar power behavior. The test procedures are illustrated using two ecological applications and a clinical trial. [ABSTRACT FROM AUTHOR]

The movement of barbel Barbus barbus free embryos in the interstitial zone and the timing of larval emergence were studied for 12 days in an artificial stream. After egg fertilization (day 1), hatching occurred on day 6, downstream interstitial movements of free embryos on day 9 and emergence and downstream movement of all larvae on day 12, with density of free embryos decreasing as day of emergence approached. The results suggest that a memory-based response of B. barbus to environmental conditions, previously observed in 0+ year juveniles, begins at an early age. [ABSTRACT FROM AUTHOR]