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Symbiotic nitrogen fixation (SNF) is a key ecological process whose impact depends on the strategy of SNF regulation—the degree to which rates of SNF change in response to limitation by N versus other resources. SNF that is obligate or exhibits incomplete downregulation can result in excess N fixation, whereas a facultative SNF strategy does not. We hypothesized that tree‐based SNF strategies differed by latitude (tropical vs. temperate) and symbiotic type (actinorhizal vs. rhizobial). Specifically, we expected tropical rhizobial symbioses to display strongly facultative SNF as an explanation of their success in low‐latitude forests. In this study we used 15N isotope dilution field experiments in New York, Oregon, and Hawaii to determine SNF strategies in six N‐fixing tree symbioses. Nitrogen fertilization with +10 and +15 g N m−2 year−1 for 4–5 years alleviated N limitation in all taxa, paving the way to determine SNF strategies. Contrary to our hypothesis, all six of the symbioses we studied sustained SNF even at high N. Robinia pseudoacacia (temperate rhizobial) fixed 91% of its N (%Ndfa) in controls, compared to 64% and 59% in the +10 and +15 g N m−2 year−1 treatments. For Alnus rubra (temperate actinorhizal), %Ndfa was 95%, 70%, and 60%. For the tropical species, %Ndfa was 86%, 80%, and 82% for Gliricidia sepium (rhizobial); 79%, 69%, and 67% for Casuarina equisetifolia (actinorhizal); 91%, 42%, and 67% for Acacia koa (rhizobial); and 60%, 51%, and 19% for Morella faya (actinorhizal). Fertilization with phosphorus did not stimulate tree growth or SNF. These results suggest that the latitudinal abundance distribution of N‐fixing trees is not caused by a shift in SNF strategy. They also help explain the excess N in many forests where N fixers are common. [ABSTRACT FROM AUTHOR]

Introduction: Associated fauna comprises most of the diversity of a coral reef and performs ecological functions essential to the reef's survival. Since Pocillopora corals harbor an important associated fauna, reef restoration efforts are underway in Golfo Dulce, Costa Rica, to preserve them. Objective: To describe changes in cryptofauna and fish communities associated with Pocillopora colonies to better understand the succession of associated fauna following transplantation. Methods: An experimental patch of 30 nursery-grown Pocillopora colonies and a control patch containing no colonies were monitored for 8 months following transplantation in Golfo Dulce. Cryptofauna within each colony and fish within each patch were observed using SCUBA to quantify temporal changes in the abundance, diversity, and community structure of the colonies. Results: The abundance and diversity of cryptofauna increased throughout the experiment. Obligate symbiont decapods were the most abundant. The composition of the community of cryptofauna differed between periods with fish in the genus Scarus as the main contributor to any differences. The increase in abundance and diversity of cryptofauna and fish may reflect coral growth and the corresponding availability of space and environmental complexity in the experimental patch. The composition of the cryptofauna communities was generally consistent with other studies. However, a high density of decapod symbionts could suggest that without other Pocillopora colonies to move to, they may crowd together despite their aggressive tendencies. Conclusions: Pocillopora colonies will experience an increase in symbionts that could positively contribute to the health and survival of the coral following transplantation. [ABSTRACT FROM AUTHOR]

Energy stores and migration are important adaptations for animals in seasonal environments, but their roles may vary relative to an animal's endogenous and exogenous environment. In partially migratory populations, migrants and residents experience different seasonal environments; thus, the influence of energy stores on survival may differ relative to migratory tactic, with potential consequences to survival and fitness.Using data from Sierra Nevada bighorn sheep (Ovis canadensis sierrae; hereafter, Sierra bighorn), we tested the hypothesis that body fat (energy stores) buffers animals against their environment, but that buffering capacity differs across environments experienced by high‐elevation residents (using a single range year‐round), traditional migrants (making 1 round‐trip movement between high‐ and low‐elevation ranges during winter) and vacillating migrants (making ≥2 round trips between high‐ and low‐elevation ranges during winter). We predicted that: for animals with high levels of body fat, survival would be high regardless of migratory tactic; residents would require larger stores of body fat to survive than migrants; energy stores would be least influential to survival for vacillating migrants.High levels of body fat in autumn (≥14% for females and ≥19% for males) largely buffered animals against harsh environments (survival >0.90) regardless of migratory tactic. At lower levels of body fat, traditional migrants had higher survival than residents. Vacillating migrants exhibited nearly 100% survival with no detectable effect of body fat on survival.Collectively, these results support the hypothesis that body fat buffers animals against harsh environments but that the buffering capacity differed relative to the environment and highly flexible behaviours (i.e. vacillating migration) can allow animals to decouple survival from body fat.Our work reveals that synergies between physiological and behavioural adaptations of animals in highly seasonal environments carry potential fitness consequences for individuals and demographic consequences for populations. Interactions among these adaptations are key to understanding nutritional prerequisites for persistence in variable environments. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study we investigated the oviposition rates and fecundity of females of Halyomorpha halys, by collecting adults soon after they entered their overwintering sites and allowing them to overwinter for 2, 3, 4 and 5 months in natural conditions of Northern Greece. We studied the occurrence of a facultative reproductive diapause in females of this insect in N. Greece by measuring the preoviposition period. According to our results, females of H. halys need an additional time period to exit diapause after they emerge from overwintering sites to mature sexually and start laying eggs. This finding is especially important to assess the possible damage of H. halys to early maturing crops for any forecasting models and thus management strategies. Halyomorpha halys (Stål) (Hemiptera: Pentatomidae) is a native pest of East Asia that overwinters as an adult in natural and human-made structures. Adult emergence from overwintering sites starts in spring, whereas females produce offspring in early summer on host plants, where most feeding occurs. In this study, we investigated the reproductive physiology of overwintering females of H. halys in Northern Greece, by determining the duration of the preoviposition period and fecundity of individuals that were left to overwinter in natural conditions and were subsequently transferred to chambers with standard conditions monthly, from December 2020 to March 2021. According to our results, overwintering H. halys females do not initiate egg laying once they emerge from overwintering sites, but rather need some additional time to exit diapause and mature reproductively. The mean preoviposition period of overwintering females that were transferred from their overwintering sites to the chambers in December 2020 was 29.0 days, which was significantly longer by 8.3 days than that of females that overwintered until March 2021, and by 13.2 days than the control (26 °C, 60% RH and a 16:8 h light: dark photoperiod). No significant difference among the average number of eggs per egg mass laid by overwintering individuals brought in the chambers in different time intervals and the laboratory colony was observed. However, females that were left to overwinter until March laid a significantly higher number of eggs in total, compared to the ones whose overwintering was disrupted in February. Based on our findings, overwintering females of H. halys experience a facultative reproductive diapause in Northern Greece. Our study was the first to determine the occurrence of diapause of H. halys in N. Greece and our findings could be very valuable for assessing the damage of this pest to early-season crops and designing successful management practices. [ABSTRACT FROM AUTHOR]

Pigeonpea is a photoperiod-sensitive crop; therefore, the introgression of photoperiod insensitivity could increase its adaptability to new environments. We determined the effect of extended daylength (ED; 16 h light) on the phenotypical traits of extra-early, early, and mid-early maturing pigeonpea introgression lines (ILs) derived from wild Cajanus species belonging to secondary and tertiary gene pools. Plants were grown under natural daylength and extended daylength in a greenhouse. Comparisons of the time of floral bud initiation, days to flowering, plant height, number of branches, and number of leaf nodes on the main stem at flowering revealed photoperiod-insensitive lines. All traits varied widely among the ILs. Analyses of flowering traits revealed large genetic components with low genotype × treatment interactions and high broad-sense heritability. The photoperiod most strongly affected the number of primary branches, followed by plant height. The extended day advanced flowering by approximately four days in extra-early ILs, confirming that these ILs are quantitative, short-day plants. The photoperiod insensitivity index varied from 0.88 in ICPP 171541 (moderately photoperiod sensitive) to 0.99 in ICPP 171546 and ICPP 171561 (photoperiod insensitive). These photoperiod-insensitive extra-early flowering ILs can be used to enrich the genetic diversity of pigeonpea and to develop photoperiod-insensitive cultivars for cultivation in new environments. [ABSTRACT FROM AUTHOR]

Embryo–environment interactions are of paramount importance during the development of all organisms, and impacts during this period can echo far into later stages of ontogeny. African annual fish of the genus Nothobranchius live in temporary pools and their eggs survive the dry season in the dry bottom substrate of the pools by entering a facultative developmental arrest termed diapause. Uniquely among animals, the embryos (encased in eggs) may enter diapause at three different developmental stages. Such a system allows for the potential to employ different regulation mechanisms for each diapause. We sampled multiple Nothobranchius embryo banks across the progressing season, species, and populations. We present important baseline field data and examine the role of environmental regulation in the embryonic development of this unique system. We describe the course of embryo development in the wild and find it to be very different from the typical development under laboratory conditions. Development across the embryo banks was synchronized within and across the sampled populations with all embryos entering diapause I during the rainy season and diapause II during the dry season. Asynchrony occurred at transient phases of the habitat, during the process of habitat desiccation, and at the end of the dry season. Our findings reveal the significance of environmental conditions in the serial character of the annual fish diapauses. [ABSTRACT FROM AUTHOR]

Embryonic diapause is an enigmatic phenomenon that appears in diverse species. Although regulatory mechanisms have been established, there is much to be discovered. Herein, we have made the first comprehensive attempt to elucidate diapause regulatory mechanisms using a computational approach. We found transcription factors unique to promoters of genes in diapause species. From pathway analysis and STRING PPI networks, the signaling pathways regulated by these unique transcription factors were identified. The pathways were then consolidated into a model to combine various known mechanisms of diapause regulation. This work also highlighted certain transcription factors that may act as 'master transcription factors' to regulate the phenomenon. Promoter analysis further suggested evidence for independent evolution for some of regulatory elements involved in diapause. [ABSTRACT FROM AUTHOR]

Necrophagy is a feeding strategy in which animals feed on carrion; most scavengers are facultative and can also be predators or consumers. For amblypygids, necrophagy is a poorly documented phenomenon and there are literature records of individuals of three different species feeding on dead bats inside caves. In the present note, we document for the first time a necrophagic behavior in the whip spider Paraphrynus raptator (Pocock, 1902) which was observed feeding on Otonyctomys hatti Anthony, 1932 (Rodentia: Cricetidae) and a yucatan poorwill, Nyctiphrynus yucatanicus Hartert, 1892 (Caprimulgiformes: Caprimulgidae) carrion.We made the observations inside a small chamber in an ancient Mayan temple inhabited by a group of woolly false vampire bats (Chrotopterus auritus Peters, 1856) in southeastern Mexico. Carrion consumption in P. raptator is directly related with the carnivorous feeding behavior of the C. auritus group with which they coexist. [ABSTRACT FROM AUTHOR]

Necrophagy is a feeding strategy in which animals feed on carrion; most scavengers are facultative and can also be predators or consumers. For amblypygids, necrophagy is a poorly documented phenomenon and there are literature records of individuals of three different species feeding on dead bats inside caves. In the present note, we document for the first time a necrophagic behavior in the whip spider Paraphrynus raptator (Pocock, 1902) which was observed feeding on Otonyctomys hatti Anthony, 1932 (Rodentia: Cricetidae) and a yucatan poorwill, Nyctiphrynus yucatanicus Hartert, 1892 (Caprimulgiformes: Caprimulgidae) carrion. We made the observations inside a small chamber in an ancient Mayan temple inhabited by a group of woolly false vampire bats (Chrotopterus auritus Peters, 1856) in southeastern Mexico. Carrion consumption in P. raptator is directly related with the carnivorous feeding behavior of the C. auritus group with which they coexist. [ABSTRACT FROM AUTHOR]

Fairly recently scavenging was thought to be restricted to a few groups of 'classic' and sometimes facultative scavengers and vultures, but what most of the more recent researches has shown is that a much wider range of groups and species are scavenger. There is a need to investigate this diversity and interactions with different communities of avian and mammalian scavengers in Turkey. The diversity of scavenger vertebrate species, their behaviour, and interactions between individuals are investigated. This study was conducted in Dörtdivan Vulture Restaurant, Bolu, Turkey. Twenty five species are recorded (eighteen birds and seven mammal) while feeding on the carcasses. The diversity of vertebrates feeding on the carcass is varied according to the carcass type. Opportunistic non-obligatory scavengers are more dominant than obligatory scavengers in this study. The intraspecific and interspecific competitions are detected between scavengers. This is the first assessment of scavenger vertebrates in Turkey. It could be the useful reference for new assessments in the future. [ABSTRACT FROM AUTHOR]

Ants are the major mutualists in the plant -ant interaction system playing a major role in the survival of plants by deterring herbivore and increasing plant health and fitness. To get better insights into the ant-plant interaction system, Clerodendrum chinense occupied by Crematogaster roghenoferi were observed for six months to assess the influence of presence and absence of ants on the flowerets blooming. In a total of (n=34) flowerets bunch, 17 were used as control and 17 experimentation that were treated with ant barrier glue to restrict the ants visitation to the flowerets bunch. By using the Students t-test, our study revealed the facultative behaviour of ants. Citing the equal presence of herbivores in both the control and experimented sets, and decreased floweret blooming in anting-continued (control) whereas increased floweret blooming in de-anted (experimented). The present study has shown the facultative interaction of C.roghenoferi with C.chinense and its effects on the reproductive structures (flowerets) of the shrub. This study makes a clear case stating that not always an interaction between ant and plant is the mutualism. [ABSTRACT FROM AUTHOR]

[Display omitted] • pMMO-related features provide the groundwork for methane-based biomanufacturing. • Multi-carbon utilization reprograms the substrate spectrum of methanotrophs. • Harnessing methanotrophs as robust microbial chassis is now being developed. • Inherent advantages can be exploited to enhance the production of various products. The development of biorefineries for a sustainable bioeconomy has been driven by the concept of utilizing environmentally friendly and cost-effective renewable energy sources. Methanotrophic bacteria with a unique capacity to utilize methane as a carbon and energy source can serve as outstanding biocatalysts to develop C1 bioconversion technology. By establishing the utilization of diverse multi-carbon sources, integrated biorefinery platforms can be created for the concept of the circular bioeconomy. An understanding of physiology and metabolism could help to overcome challenges for biomanufacturing. This review summaries fundamental gaps for methane oxidation and the capability to utilize multi-carbon sources in methanotrophic bacteria. Subsequently, breakthroughs in harnessing methanotrophs as robust microbial chassis for industrial biotechnology were compiled and overviewed. Finally, challenges and capabilities to exploit the inherent advantages of methanotrophs to synthesize various target products in higher titers are proposed. [ABSTRACT FROM AUTHOR]

Abstract It is challenging to capture N-glycopeptides with high recovery and high specificity from complicated biosystems. Herein, we present a facile and economical procedure to generate a novel self-assembling 4-Mercaptobenzene boronic acid functionalized and Au-doped Straticulate C 3 N 4 (MASC), with enhanced affinity capability towards glycopeptides. The materials possess low pH value adaptation, high hydrophilicity and stability, good repeatability and recyclability, and provided high selectivity (1:100), low limit of detection (0.33 fmol/μL), high enrichment efficiency (~ 80%) and high recovery rate (~ 90%) towards glycopeptides. The materials can capture glycopeptides unbiasedly, as demonstrated by the identification of 37 glycopeptides from IgG and 21 glycopeptides from horseradish peroxidase (HRP). The performance of MASC on human urine and serum glycoproteome analysis was also tested. An average of 1465 glycopeptides from 839 glycoproteins and 1553 glycopeptides from 884 glycoproteins were identified from female and male urine samples in a single mass spectrometry analysis. O -glycopeptides from human urine were also significantly enriched. Additionally, 463 glycopeptides assigned to 209 glycoproteins were identified from 5 μL of human serum. All of these results indicate that MASC presents a good performance and applicability in the field of glycoproteomic research. Graphical abstract fx1 Highlights • A facile and economical procedure to generate phenylboronic acid functionalized C3N4 facultative hydrophilic materials was developed. • The new materials possess the properties of low pH value adaptation, high hydrophilicity and stability. • In the enrichment of glycopeptides, the materials show high selectivity (1:100), low limit of detection (0.33 fmol/μL), high enrichment efficiency (~ 80%) and high recovery rate (~ 90%). • Compared to previous studies, the materials captured more glycopeptides from human urine and serum. [ABSTRACT FROM AUTHOR]

Abstract: A key adaptation in insects for dealing with variable environmental conditions is the ability to diapause. The tiger swallowtail butterflies, Papilio glaucus and P. canadensis are ideal species to explore the genetic causes and population genetic consequences of diapause because divergence in this trait is believed to be a salient factor in maintaining a hybrid zone between these species. Yet little is known about the factors that influence diapause induction in this system. Here we explored how spatial (latitudinal), environmental (temperature) and genetic (hybridization) factors affect diapause induction in this system. Specifically, a series of growth chamber experiments using wild caught individuals from across the eastern United States were performed to: (1) evaluate how critical photoperiod varies with latitude, (2) isolate the stage in which induction occurs, (3) test whether changes in temperature affected rates of diapause induction, and (4) explore how the incidence of diapause is affected in hybrid offspring. We find that induction occurs in the larval stage, is not sensitive to a relatively broad range of temperatures, appears to have a complex genetic basis (i.e., is not simply a dominant trait following a Mendelian inheritance pattern) and that the critical photoperiod increases by 0.4 h with each increasing degree in latitude. This work deepens our understanding of how spatial, environmental and genetic variation influences a key seasonal adaptation (diapause induction) in a well‐developed ecological model system and will make possible future studies that explore how climatic variation affects the population dynamics and genetics of this system. [ABSTRACT FROM AUTHOR]

Facultatively social species exhibit behavioral plasticity in response to changes in ecological conditions and social environment, and thus provide a natural experiment to compare solitary and social behaviors in a single genome. Such species can therefore provide empirical insights into the evolution of eusociality. The small carpenter bees (genus Ceratina) and sweat bees (Halictidae) are of special interest because they exhibit rich behavioral plasticity. Species range from solitary to eusocial, and both groups benefit from detailed behavioral research and well-established phylogenies. As such, small carpenter and sweat bees are poised to further comparative sociogenomic studies which emphasize the necessity of a molecular phylogeny for understanding the evolution of molecular architecture underlying social phenotypes and organizational complexity. Here, we review behavioral, transcriptomic and genomic data in bees across the social spectrum, highlighting the importance of simple societies and facultatively social taxa to examine the genetic basis of cooperative traits and social evolution. [ABSTRACT FROM AUTHOR]

Through the removal of parasites, dead skin and mucus from the bodies of visiting reef fish (clients), cleaner fish have a significant ecosystem function in the ecology of coral reefs. Cleaners gain nutrition from these interactions and through offering a ‘service’ are afforded protection from predators. Given these benefits, it is unclear why more fish do not engage in cleaning, and why part-time cleaning strategies exist. On coral reefs, dedicated species clean throughout their life, whereas some species are facultative, employing opportunistic and/or temporary cleaning strategies. Here, we investigate the cleaning behaviour of a facultative species to assess the relative importance of this interaction to the cleaner. Using a combination of focal and event sampling from a coral reef in Tobago, we show that cleaning is not an essential food source for facultative juvenile blue-headed wrasse ( Thalassoma bifasciatum ), as cleaning rate was unrelated to their foraging rate on the substrate. These wrasse displayed two cleaning strategies: stationary versus wandering cleaning, with cleaning frequency being highest for stationary cleaners. A specific cleaning location facilitated increased cleaning frequency, and wrasse cleaning rate decreased as cleaner or client abundance increased. We also compared juvenile blue-headed wrasse cleaning behaviour to a resident dedicated cleaner, the sharknose goby ( Elacatinus evelynae ), and showed that, in comparison, juvenile wrasse clean a narrower client range, predominately cleaning three species of gregarious free-ranging surgeonfish ( Acanthurus spp.). The wrasse, however, frequently approached these clients without cleaning, which suggests that their selective cleaning strategy may be driven by the acquisition of a particular parasitic food source. Juvenile blue-headed wrasse are generalist foragers, and may thus be limited in their cleaning behaviour by their nutritional requirements, the availability of a suitable cleaning site, and fish density, which ultimately means that they do not adopt more dedicated cleaning roles within the reef community. [ABSTRACT FROM AUTHOR]

The anabantoids are a group of c. 137 species of air-breathing freshwater fishes found in Africa and southern Asia. All anabantoids have a pair of suprabranchial chambers that each house an air-breathing organ known as the labyrinth apparatus: a complex bony structure lined with thin, highly vascularised respiratory epithelium. The labyrinth apparatus allows anabantoids to extract oxygen from air and is a morpho-physiological innovation that has had a dramatic influence on the behaviour of these fishes. Air-breathing influences a wide range of anabantoid behaviours, including territorial displays, courtship and breeding and parental care and also equips these fishes to persist in hypoxic and polluted water. These traits also make anabantoids successful invaders of novel habitats, a global problem compounded by their popularity in the aquarium trade. By reviewing the functionality and evolution of air breathing in anabantoids, this review aims to examine the role of the labyrinth apparatus in modulating behaviour within this group. The anabantoids are a fascinating group and have often been cited as a model organism due to the stereotypical and easily identifiable behaviours that they adopt during social interactions. They also provide a unique opportunity to further our understanding about how fishes adapt their behaviour in response to an extreme environment, whilst limited by their own physiological constraints. [ABSTRACT FROM AUTHOR]

There exists a kind of symbiotic bacterium named ' Candidatus Arsenophonus nilaparvatae' in the brown planthopper (BPH), Nilaparvata lugens. After being filtered and assembled from the BPH genome sequencing project, the genome sequence of this bacterial symbiont was obtained. After initial analysis based on the genome, we have found its potential role to synthesize B vitamins for the host. In order to better understand the lifestyle and the genomic changes of this symbiotic bacterium after the symbiotic relationship was established, we further report the characteristics of this draft genome. Compared with several other related bacteria, ' Candidatus Arsenophonus nilaparvatae' has proven to be a facultative endosymbiont at the genomic level. Concurrently, the presence of fimbriae and flagella formation related genes indicates this maternally transmitted endosymbiont is most likely to retain the capacity to invade new hosts. Through further analysis of annotated gene sets, we also find evidence of genome reduction in its secretion system and metabolic pathways. These findings reflect its evolutionary trend to be an obligate one and enable a deeper study of microbe-insect interactions. [ABSTRACT FROM AUTHOR]

Facultative autotrophs are abundant components of communities inhabiting geothermal springs. However, the influence of uptake kinetics and energetics on preference for substrates is not well understood in this group of organisms. Here, we report the isolation of a facultatively autotrophic crenarchaeote, strain CP80, from Cinder Pool (CP, 88.7°C, pH 4.0), Yellowstone National Park. The 16S rRNA gene sequence from CP80 is 98.8% identical to that from Thermoproteus uzonensis and is identical to the most abundant sequence identified in CP sediments. Strain CP80 reduces elemental sulfur (S8°) and demonstrates hydrogen (H2)-dependent autotrophic growth. H2-dependent autotrophic activity is suppressed by amendment with formate at a concentration in the range of 20-40μM, similar to the affinity constant determined for formate utilization. Synthesis of a cell during growth with low concentrations of formate required 0.5μJ compared to 2.5μJ during autotrophic growth with H2. These results, coupled to data indicating greater C assimilation efficiency when grown with formate as compared to carbon dioxide, are consistent with preferential use of formate for energetic reasons. Collectively, these results provide new insights into the kinetic and energetic factors that influence the physiology and ecology of facultative autotrophs in high-temperature acidic environments. [ABSTRACT FROM AUTHOR]

During the practice of medicine there are times where the doctor must take important decisions, particularly in situations of life and death of a patient. In the current circumstances and the proliferation of complaints of malpractice or negligence, appropriate prophylaxis to prevent a large number of these actions and prevent the growing trend is necessary. The issue of professional responsibility in health is now a matter of broad discussion in our country and in the world as it should be, due to the increasing number of complaints, claims and demands arising from the provision of medical services, situation that forces us to reflect on the causes that have led to its growth and, especially, requires particularly medical and legal community with a deep knowledge of the subject, as in the solution of these controversies is involved one of the fundamental interests he attends all Mexicans: the right to receive appropriate health benefits and quality. [ABSTRACT FROM AUTHOR]

Phytoremediation is a cost-effective and environment friendly method for cleaning metal(loid)s from contaminated soils. Species with exceptionally higher shoot metal concentrations (hyperaccumulators) seem ideal for phytoremediation, though some metal tolerant species with 'above normal' values with higher translocation factor (TF) may also serve the purpose. Halophytes not only remove salts and metalloids from soils but may also be cultivated as non-conventional crops. Nurturing halophytes requires precise understanding of their nature and efficient management for sustainable use. Species with low metal concentrations in their edible parts (especially leaves) may be grown as forage and fodder, but those with metal hyperaccumulation could prove fatal due to their serious health hazards. Like other metallophytes, redundant use of the term 'metal hyperaccumulation' among halophytes needs to be revisited for its ambiguity and potential pitfalls. Similarly, understanding of metal tolerance and shoot accumulation nature of halophytes is needed prior to their use. This review is an attempt to compare halophytes with potential of metal bioindication, phytostabilization and hyperaccumulation (as per definition) as well as their 'obligate' and 'facultative' nature for appropriate uses. [Display omitted] • This review outlined opacity regarding the terms bioindication, phytostabilization and metal hyperaccumulation among halophytes. • Obligate and facultative metal hyperaccumulating halophytes have been enlisted for the first time. • Based on shoot metal concentrations, multipurpose use of halophytes has been proposed. [ABSTRACT FROM AUTHOR]

Phytoremediation is a cost-effective and environment friendly method for cleaning metal(loid)s from contaminated soils. Species with exceptionally higher shoot metal concentrations (hyperaccumulators) seem ideal for phytoremediation, though some metal tolerant species with 'above normal' values with higher translocation factor (TF) may also serve the purpose. Halophytes not only remove salts and metalloids from soils but may also be cultivated as non-conventional crops. Nurturing halophytes requires precise understanding of their nature and efficient management for sustainable use. Species with low metal concentrations in their edible parts (especially leaves) may be grown as forage and fodder, but those with metal hyperaccumulation could prove fatal due to their serious health hazards. Like other metallophytes, redundant use of the term 'metal hyperaccumulation' among halophytes needs to be revisited for its ambiguity and potential pitfalls. Similarly, understanding of metal tolerance and shoot accumulation nature of halophytes is needed prior to their use. This review is an attempt to compare halophytes with potential of metal bioindication, phytostabilization and hyperaccumulation (as per definition) as well as their 'obligate' and 'facultative' nature for appropriate uses. [Display omitted] • This review outlined opacity regarding the terms bioindication, phytostabilization and metal hyperaccumulation among halophytes. • Obligate and facultative metal hyperaccumulating halophytes have been enlisted for the first time. • Based on shoot metal concentrations, multipurpose use of halophytes has been proposed. [ABSTRACT FROM AUTHOR]

Research regarding the pollination mechanism of federally endangered Hexastylis naniflora was conducted during spring and summer 2009 in Cleveland County, North Carolina. Research focused on the possible role of insect pollinators in pollination success. Caging was used to exclude insects from 30 flowers, from 30 different plants, in order to examine differences in a final percent seed set of fruits developed from both caged and open flowers. Though caged flowers did show partial seed set, a significant difference in percent seed set was found between the control and experimental groups (t = 3.678, df = 26.482, p = 0.001, n = 29 flowers) indicating pollination is the result of a compound, facultative mechanism, which includes both entomophily and some other, undetermined, self-pollinating capability. [ABSTRACT FROM AUTHOR]

Several taxonomically disparate groups of fishes have evolved the ability to extract oxygen from the air with elements of their gut. Despite perceived difficulties with balancing digestive and respiratory function, gut air breathing ( GAB) has evolved multiple times in fishes and several GAB families are among the most successful fish families in terms of species numbers. When gut segments evolve into an air-breathing organ ( ABO), there is generally a specialized region for exchange of gases where the gut wall has diminished, vascularization has increased, capillaries have penetrated into the luminal epithelium and surfactant is produced. This specialized region is generally separated from digestive portions of the gut by sphincters. GAB fishes tend to be facultative air breathers that use air breathing to supplement aquatic respiration in hypoxic waters. Some hindgut breathers may be continuous, but not obligate air breathers (obligate air breathers drown if denied access to air). Gut ABOs are generally used only for oxygen uptake; CO2 elimination seems to occur via the gills and skin in all GAB fishes studied. Aerial ventilation in GAB fishes is driven primarily by oxygen partial pressure of the water ( PO2) and possibly also by metabolic demand. The effect of aerial ventilation on branchial ventilation and the cardiovascular system is complex and generalizations across taxa or ABO type are not currently possible. Blood from GAB fishes generally has a low blood oxygen partial pressure that half saturates haemoglobin ( p50) with a very low erythrocytic nucleoside triphosphate concentration [ NTP]. GAB behaviour in nature depends on the social and ecological context of the animal as well as on physiological factors. [ABSTRACT FROM AUTHOR]

The evolution of air breathing during the Devonian provided early fishes with bimodal respiration with a stable O2 supply from air. This was, however, probably associated with challenges and trade-offs in terms of acid-base balance and ionoregulation due to reduced gill:water interaction and changes in gill morphology associated with air breathing. While many aspects of acid-base and ionoregulation in air-breathing fishes are similar to water breathers, the specific cellular and molecular mechanisms involved remain largely unstudied. In general, reduced ionic permeability appears to be an important adaptation in the few bimodal fishes investigated but it is not known if this is a general characteristic. The kidney appears to play an important role in minimizing ion loss to the freshwater environment in the few species investigated, and while ion uptake across the gut is probably important, it has been largely unexplored. In general, air breathing in facultative air-breathing fishes is associated with an acid-base disturbance, resulting in an increased partial pressure of arterial CO2 and a reduction in extracellular pH ( pHE); however, several fishes appear to be capable of tightly regulating tissue intracellular pH ( pHI), despite a large sustained reduction in pHE, a trait termed preferential pHI regulation. Further studies are needed to determine whether preferential pHI regulation is a general trait among bimodal fishes and if this confers reduced sensitivity to acid-base disturbances, including those induced by hypercarbia, exhaustive exercise and hypoxia or anoxia. Additionally, elucidating the cellular and molecular mechanisms may yield insight into whether preferential pHI regulation is a trait ultimately associated with the early evolution of air breathing in vertebrates. [ABSTRACT FROM AUTHOR]

Highlights: [•] We review research on plants that hyperaccumulate metals but also occur on low-metal soils. [•] Facultative hyperaccumulators are rare but include several well-known research models. [•] Research on facultative hyperaccumulators has focused disproportionately on a few species. [•] Future studies need to focus on plants from other phylogenetic and geographic groups. [•] We propose new hypotheses regarding the evolution of facultative hyperaccumulation. [ABSTRACT FROM AUTHOR]

The strain NSC3, a novel, facultative, chemolithotrophic, denitrifying, alkaliphilic, sulfide-oxidizing bacterium isolated from a hot spring in Yang-Ming Mountain, Taiwan, was Gram negative, rod shaped, and motile by single polar flagella and grew facultatively by adopting a denitrifying metabolism. The 16S rRNA sequence analysis revealed that strain NSC3 belongs to beta subclass of the Proteobacteria and most closely related to Azoarcus evansii KB740 (95.44 %), Azoarcus toluvorans Td-21 (95.21 %), Azoarcus tolulyticus Tol-4 (95.08 %), and Azoarcus toluclasticus MF63 (94.94 %). The phylogenetic analyses based on 16S rRNA gene sequences indicated that the strain NSC3 formed a distinct lineage in the Betaproteobacteria and that it exhibited the highest level of sequence similarity with species of the genera Azoarcus (95.28-93.13 %). The major fatty acids of the type strain were C (26.9 %), C (28.9 %), C (9.6 %), and C (29.9 %). The DNA G+C content of genomic DNA was 63.7 mol%. On the basis of the 16S rRNA sequence similarity, phenotypic and genotypic characteristics, and chemotaxonomic data, the strain NSC3 could be differentiated from other species of the genus Azoarcus. Therefore, strain NSC3 (equal to BCRC 80111 and DSM 24109) is proposed as a novel species in genus Azoarcus, for which the name Azoarcus taiwanensis sp. nov. is proposed. The strain NSC3 is deposited in Bioresource Collection and Research Center, Taiwan, under the reference number BCRC 80111, and German Collection of Microorganisms and Cell Cultures, Germany (DSMZ), with DSM 24109. [ABSTRACT FROM AUTHOR]

Waste stabilization ponds (WSP) were designed to treat 287.5 m3 day-1 of wastewater generated from processing of 100 m3 of milk per day. The design involved use of existing models including those developed by Mara to size the anaerobic, facultative and maturation ponds. The design temperature was 25°C. The anaerobic pond was designed based on volumetric organic loading rate while facultative pond was designed based on surface loading rate. On the other hand, the maturation pond was designed based on the number of coliform bacteria removed per 100 mL of wastewater. The anaerobic pond was designed to remove 70% BOD, facultative pond-75% and maturation pond-25% BOD. In addition, the maturation pond was designed to have a coliform bacteria removal efficiency of at least 99%. The total land requirement for anaerobic pond was estimated at 945.19 m2, facultative pond-6361.54 m2 and three maturation ponds-2709.06 m2. To cater for pond operation and maintenance, an additional 25% land was incorporated resulting into 1.25 hectares as the total land area required for pond construction, operation and maintenance. Besides treatment of wastewater to reduce BOD, remove pathogens and other pollutants, the use of WSP can result into high economic benefits through recycling of wastewater for agriculture and aquaculture. As a result, the payback period for the investment cost may also be shortened [ABSTRACT FROM AUTHOR]

In humid ecosystems, the rate of methane ( CH4) oxidation by soil-dwelling methane-oxidizing bacteria ( MOB) is controlled by soil texture and soil water holding capacity, both of which limit the diffusion of atmospheric CH4 into the soil. However, it remains unclear whether these same mechanisms control CH4 oxidation in more arid soils. This study was designed to measure the proximate controls of potential CH4 oxidation in semiarid soils during different seasons. Using a unique and well-constrained 3-million-year-old semiarid substrate age gradient, we were able to hold state factors constant while exploring the relationship between seasonal potential CH4 oxidation rates and soil texture, soil water holding capacity, and dissolved organic carbon ( DOC). We measured unexpectedly higher rates of potential CH4 oxidation in the wet season than the dry season. Although other studies have attributed low CH4 oxidation rates in dry soils to desiccation of MOB, we present several lines of evidence that this may be inaccurate. We found that soil DOC concentration explained CH4 oxidation rates better than soil physical factors that regulate the diffusion of CH4 from the atmosphere into the soil. We show evidence that MOB facultatively incorporated isotopically labeled glucose into their cells, and MOB utilized glucose in a pattern among our study sites that was similar to wet-season CH4 oxidation rates. This evidence suggests that DOC, which is utilized by MOB in other environments with varying effects on CH4 oxidation rates, may be an important regulator of CH4 oxidation rates in semiarid soils. Our collective understanding of the facultative use of DOC by MOB is still in its infancy, but our results suggest it may be an important factor controlling CH4 oxidation in soils from dry ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Caulobacteria are presumed to be responsible for considerable mineralization of organic material in aquatic environments. In this study, a facultative, mesophilic and cellulolytic bacterium Caulobacter sp. FMC1 was isolated from sediments which were taken from a shallow freshwater lake and then enriched with amendment of submerged macrophyte for three months. This strain seemed to evolve a capacity to adapt redox-fluctuating environments, and could degrade cellulose both aerobically and anaerobically. Cellulose degradation percentages under aerobic and anaerobic conditions were approximately 27% and 10% after a 240-h incubation in liquid mediums containing 0.5% cellulose, respectively. Either cellulose or cellobiose alone was able to induce activities of endoglucanase, exoglucanase, and β-1,4-glucosidase. Interestingly, ethanol was produced as the main fermentative product under anaerobic incubation on cellulose. These results could improve our understanding about cellulose-degrading process in aquatic environments, and were also useful in optimizing cellulose bioconversion process for bioethanol production. [Copyright &y& Elsevier]

Partner abundance affects costs and benefits in obligate mutualisms, but its role in facultative partnerships is less clear. We address this gap in a pollination web consisting of two clovers (Trifolium) that differ in specialization on a bumble bee pollinator Bombus balteatus. We examine how pollination niche breadth affects plant responses to pollinator abundance, comparing early-flowering (specialized) and late-flowering (generalized) cohorts of T. parryi and early T. parryi to T. dasyphyllum, a pollination generalist. Co-pollinators disrupt the link between B. balteatus visitation and pollination rate for both clovers. Only for early-flowering T. parryi do visitation, pollination, and seed set increase with density of B. balteatus. Bumble bee density also alters timing of seed germination in T. parryi, with seeds from plants receiving augmented B. balteatus germinating sooner than seeds of open-pollinated counterparts. Benefits saturate at intermediate bumble bee densities. Despite strong effects of B. balteatus density on individual plant fitness components, population models suggest little impact of B. balteatus density on &lgr; in T. parryi or T. dasyphyllum. Findings show that functional redundancy in a pollinator guild mediates host-plant responses to partner density. Unexpected effects of pollinator density on life history schedule have implications for recruitment under pollinator decline. [ABSTRACT FROM AUTHOR]

A comprehensive review of the morphology, anatomy, taxonomy, chemistry and ecology of the endemic New Zealand facultative shrub epiphyte Pittosporum cornifolium (Pittosporaceae) is presented. Strong habitat specificity restricts this species to lowland forest and coastal habitats, which are widely yet discontinuously distributed north of latitude 42°15′S. Pittosporum cornifolium is typically associated with old growth forest systems and low nutrient substrates, with low mean daily temperatures in the coldest month (<0.6 °C) and high mean October vapour pressure deficits (>0.5 kPa) apparently restricting its distribution. Significant morphological variability is evident in leaves and flowers, especially with respect to plants from the Poor Knights Islands. Genetic analyses of five mainland populations and individuals representing Poor Knights Islands populations revealed relatively low genetic diversity at the population level which is likely to be the result of geographic isolation. Molecular phylogenetic studies suggest a New Caledonian origin for the species with close affinities to both P. pimeleoides subspecies. Several lines of evidence suggest recognition of the Poor Knights Islands entity as a new taxon. However, analysis of additional morphological, reproductive and molecular data across the full geographic range will be required to confirm current inferences. Although populations have declined, P. cornifolium is not currently threatened, however, it should be considered for reintroduction to sites in districts where its range has been severely reduced. [ABSTRACT FROM PUBLISHER]

The term amphidromous was coined (Myers in Copeia 1949:89-97, ) to describe diadromous life histories that include migrations, not associated with reproduction, that are between fresh and marine waters. This concept has facilitated evaluations of life cycles among a number of groups of fishes including some belonging to the family Eleotridae. Information was gathered on life history patterns of eleotrid fish species that have been recorded from both fresh and brackish or marine waters of the east and west coasts of North, Middle, and South America, including adjacent islands, seeking evidence of diadromy and especially of amphidromy. Convincing evidence was found of diadromy in the life cycles of four species from the east coast (with another two species possibly in this category), and of three species from the west coast of the Americas and adjacent islands. However, there was convincing evidence of amphidromy in only one species from the east coast and adjacent islands, with another three species or species populations possibly in this category, and in three species from the west coast and adjacent islands. It seems possible from the available information that there may be variation among populations in life cycles of some of these species. However, it remains for the use of modern techniques to allow more definitive determinations of life history patterns of these eleotrid species populations. Serious concern exists with respect to the conservation of all diadromous species because of the worldwide emphasis on river manipulations, especially of dam construction. Resident diadromous organisms are being impeded in their migrations, and thus imperiled in their potential for survival, depending on the nature of river alterations and the abilities of the organisms to cope with them. [ABSTRACT FROM AUTHOR]

In current study an analytical and comparative study of post treatment options for UASB reactor treating municipal wastewater is presented. The two important post treatment alternatives viz. facultative waste stabilization pond and aerated lagoon are considered, lagoon and pond refer broadly to basins constructed in, or on the ground surface, using earthen dikes to retain the wastewater within which natural stabilization process occur with the necessary oxygen coming from atmospheric diffusion, photosynthetic and / or mechanical sources. [ABSTRACT FROM AUTHOR]

Parthenocarpy is a condition where an ovary develops into a fruit without fertilization and seed formation. Parthenocarpy might be useful in breeding tomato (Lycopersicon esculentum Mill.) to be adapted to a wide range of temperatures normally unfavorable for fruit setting. The expression of parthenocarpy in tomato, cv. Oregon Pride, was facultative with seedless, few seeded (1-20 seed(s)/fruit), and normal seeded fruit being produced on the same plant in the same growing season. The greatest degree of parthenocarpy, leading to seedlessness, occurred above a daily mean temperature of 24-25˚C. When there was sufficient viable pollen, and an appropriate daily mean temperature of 18-21˚C, there was some fertility leading to low numbers of seed produced. Very low fruit set following emasculation compared to open pollination indicated the requirement of pollination stimulus for fruit set and further development. Precocious ovary development due to genetic stimuli combined with aberration of female fertility by interfering with ovule development might account for very low seed content in fruit of facultative parthenocarpic lines. [ABSTRACT FROM AUTHOR]

Aquatic insects inhabiting Okhuo River, in a tropical forest near Benin City, Southern Nigerian, were studied between January and December 2006 to determine the taxa composition, diversity, EPT index, relative proportions of the various groups and hence the pollution level of the waterbody. Three stations were selected and sampled monthly using the kick sampling technique. A total of 3235 individual aquatic insects belonging to 24 taxa distributed among 23 genera in six orders were collected. The insect orders occurred in the following order of dominance: Ephemeroptera > Odonata > Coleoptera > Diptera > Plecoptera > Tricoptera. Based on the diverse composition of the community dominated by organisms intolerant of organic enrichment, and the high diversity and EPT index, water quality in Okhuo River is not significantly degraded. Community composition varies seasonally, with a trend toward a declining proportion during the rainy season and increasing proportions during the dry season. Aquatic insect composition in Okhuo River compares favourably with those in similar, relatively undisturbed forest streams and rivers in Nigeria, but the diversity and proportional distribution of taxa vary considerably between streams. [ABSTRACT FROM AUTHOR]

The author discusses aspects of ecology and the nitrogen influences causing the abundance and distribution of species in terrestrial and aquatic ecosystem. He cites the study by Menge and Chazdon on higher survival that drives the success of nitrogen-fixing trees in the rainforest of Costa Rica. The author thinks that the study provides a sensible explanation on the role of nitrogen (N) limitation based on the degree and persistence of disturbance.

The evolution of intracellular pathogens is considered in the context of ambiguities in basic definitions and the diversity of host-microbe interactions. Intracellular pathogenesis is a subset of a larger world of hostmicrobe interactions that includes amoeboid predation and endosymbiotic existence. Intracellular pathogens often reveal genome reduction. Despite the uniqueness of each host-microbe interaction, there are only a few general solutions to the problem of intracellular survival, especially in phagocytic cells. Similarities in intracellular pathogenic strategies between phylogenetically distant microbes suggest convergent evolution. For discerning such patterns, it is useful to consider whether the microbe is acquired from another host or directly from the environment. For environmentally acquired microbes, biotic pressures, such as amoeboid predators, may select for the capacity for virulence. Although often viewed as a specialized adaptation, the capacity for intracellular survival may be widespread among microbes, thus questioning whether the intracellular lifestyle warrants a category of special distinctiveness. [ABSTRACT FROM AUTHOR]

This paper evaluates the feasibility of a membrane-coupled methanogenic and facultative bioreactor (MCMFB) system in treating the wastewater from the liquid crystal display (LCD)-related industry. The treatment unit is comprised of an anaerobic (methanogenic) and an aerobic reactor. The hollow fiber membrane module (0.036 μm) was submerged in the aerobic reactor for solids/liquid separation. An average 80% COD removal was achieved in the anaerobic reactor when the volumetric loading reached 7.2 kg COD/m3 per day. The effluent of the anaerobic treatment was fed into the aerobic-membrane tank to treat the residual COD. The mixed liquor suspended solids of the aerobic tank was 7000 mg/L with an average F/M of 0.14 g COD/g SS per day, and the removal efficiency of the aerobic tank was 90% in average. The transmembrane pressure and the flux of the membrane remained stable during the entire period of the 140-day operation without any backwash or chemical wash, indicating the applicability of the MCMFB system on treating the targeted wastewater. [ABSTRACT FROM AUTHOR]

A survey of the hemi-epiphytes and other herbaceous facultative epiphytes was performed in Kibale National Park. A total of 100 major host trees were sampled in detail by a canopy-based single rope technique. A total of thirteen families, thirteen genera with 24 species were found being dominated in terms of species by the family Moraceae with nine species. The most common Ficus species were F. sasibarica and F. conracii, while the herbaceous facultative epiphytes had Rhipsalis baccifera, Peperomia manni and P. tetraphylla as the most common. Correlation analysis revealed no relationship between basal area and the Ficus species. The herbaceous facultative epiphytes increased significantly with increase in the host basal area. Ficus species and the herbaceous facultative epiphytes preferred the ‘base’ and ‘mid’ branch zones of the host trees characterized by a narrow range of vertical distribution in both the logged and un-logged forests. Most species were found in the ‘light’ and ‘heavy’ humus type of substrates. There was a tendency for the logged forests to have more hemi-epiphytes and the herbaceous facultative epiphytes than the un-logged forest types. [ABSTRACT FROM AUTHOR]

To better understand the dynamics of Fe2 + oxidation in facultative wastewater stabilization ponds, water samples from a three-pond system were taken throughout the period of transition from anoxic conditions with high aqueous Fe2 + levels in the early spring to fully aerobic conditions in late spring. Fe2 + levels showed a highly significant correlation with pH but were not correlated with dissolved oxygen (DO). Water column Fe2 + levels were modeled using the kinetic rate law for Fe2 + oxidation of Sung and Morgan. [5] The fitted kinetic coefficients were 5 ± 3 × 106 M-2 atm-1 min-1; more than six orders of magnitude lower than typically reported. Comparison of four potential Fe redox couples demonstrated that the pε was at least 3–4 orders of magnitude higher than would be expected based on internal equilibrium. Surprisingly, measured nitrate and DO (when present) were typically consistent with both nitrate (from denitrification) and DO levels (from aerobic respiration) predicted from equilibrium. Although the hydrous Fe oxide/FeCO3 couple was closest to equilibrium and most consistent with the observed pH dependence (in contrast to predicted lepidocrocite), Fe2 + oxidation is kinetically hindered, resulting in up to 107-fold higher levels than expected based on both kinetic and equilibrium analyses. [ABSTRACT FROM AUTHOR]

Abstract: Occasional use of arboreal habitats is common in many otherwise-terrestrial species, but the functions of facultative arboreality remain unclear. Red-sided garter snakes (Thamnophis sirtalis parietalis) are small nonvenomous terrestrial snakes, recorded to climb only rarely. During springtime fieldwork near a large communal overwintering den in Manitoba, we observed occasional episodes when hundreds of snakes climbed into low trees and remained in the branches for periods ranging from minutes to hours. Our data suggest a thermoregulatory basis for this behaviour. During daylight hours when the snakes were active, ambient temperatures generally were higher on the ground than in trees; but this thermal cline reversed occasionally, especially after the ground was cooled by light rain. Arboreality was most common during those thermal reversals. Experimentally simulating rain in the field (sprinkling with water) induced climbing behaviour; and in laboratory enclosures, snakes climbed to avoid a cold substrate. Thus, red-sided garter snakes ascend trees to access higher temperatures than are available on the ground. [Copyright &y& Elsevier]

1. Pollen is considered to be an important dietary component for many species of flower-feeding herbivores. Its influence on oviposition site selection by the pollen beetle Meligethes aeneus, and on the development of its larvae was investigated. 2. The effects of pollen presence and absence on adult, egg, and larval incidence in the field, and on larval development in the laboratory were compared through the use of Synergy, a composite hybrid oilseed rape Brassica napus variety comprising male-fertile (with pollen) and male-sterile (without pollen) plants. 3. In the field, adult females were more abundant on male-fertile plants during flowering, and a greater proportion of male-fertile than male-sterile buds were accepted for oviposition. These data indicate a possible role of pollen in oviposition site selection by female pollen beetles. 4. The numbers of first instar larvae on the two plant lines did not differ; however, more second instars were found on male-fertile than on male-sterile flowers. This suggests a greater larval survival on male-fertile plants, possibly due to the more readily available food resources and better nutrition afforded by the presence of pollen. 5. Laboratory experiments confirmed that a diet which included pollen improved survival to adulthood and resulted in heavier pupae and adults; however, pollen was not obligatory for larval survival and development. 6. The pollen beetle, previously thought to be an obligate pollen feeder, is therefore more generalist in its requirements for development. These findings may relate to the nutritional and behavioural ecology of other flower-feeding herbivores. [ABSTRACT FROM AUTHOR]

Abstract The life history of the mistletoe-feeding butterfly Ogyris amaryllis is commonly thought to involve an obligate association with ants. The distribution of eggs of subspecies O. a. meridionalis Bethune-Baker, which occurs over much of the Australian interior, is strongly associated with Iridomyrmex ants. This study examined the level and frequency of ant association exhibited by larvae and pupae of O. a. amaryllis , which occurs in coastal areas of eastern Australia. The distribution of juveniles was compared with that of ants at the scale of sites, mistletoe host trees, and larval sheltering locations. A significant positive association between larvae and ants was detected, although this association was weak and non-specific, indicating that O. a. amaryllis is facultatively myrmecophilous. Observed ant attendance of larvae was uncommon (5.6%). Available evidence suggests that either plasticity exists in the degree of myrmecophily of O. amaryllis , with different degrees of association expressed under different ecological circumstances, or different degrees of myrmecophily are characteristic of subspecific status. [ABSTRACT FROM AUTHOR]

Since the discovery of phages in 1915, these viruses have been studied mostly in aerobic systems, or without considering the availability of oxygen as a variable that may affect the interaction between the virus and its host. However, with such great abundance of anaerobic environments on the planet, the effect that a lack of oxygen can have on the phage-bacteria relationship is an important consideration. There are few studies on obligate anaerobes that investigate the role of anoxia in causing infection. In the case of facultative anaerobes, it is a well-known fact that their shifting from an aerobic environment to an anaerobic one involves metabolic changes in the bacteria. As the phage infection process depends on the metabolic state of the host bacteria, these changes are also expected to affect the phage infection cycle. This review summarizes the available information on phages active on facultative and obligate anaerobes and discusses how anaerobiosis can be an important parameter in phage infection, especially among facultative anaerobes. [ABSTRACT FROM AUTHOR]

Although inquilinism in the goby–alpheid shrimp association is well known, behavior inside the burrow remains unclear because it is difficult to observe. In this tank study, alpheid shrimp burrow morphology was investigated because it may reflect the behavior of the burrow inhabitants. The objective was to elucidate the effects of Acentrogobius sp. 2 (sensu Akihito et al., 2013) on the burrow morphology of Alpheus brevicristatus. Through mesocosm experiments, 12 burrows made by shrimp without goby (solitary treatment), and 14 burrows made by shrimp with goby (symbiotic treatment), were recovered. Differences between solitary and symbiotic treatments were identified using a univariate test of each burrow parameters (total depth, total length, horizontal extension, diameter, number of openings, and number of side branches) and multivariate methods (nMDS and ANOSIM). Results indicate that the effect of the symbiotic goby on the shrimp burrow is small or smaller than the effect of shrimp size. However, the treatments varied significantly in terms of the correlation between shrimp size and each burrow parameter. In the solitary treatment, almost all the burrow parameters showed a high correlation with shrimp carapace length, suggesting that the burrow size was optimal for the shrimps. In contrast, no significant correlation was observed between most of the burrow parameters and shrimp size in the symbiotic treatment. Smaller burrows may not be suitable for the shrimp, and larger burrows require more energy to construct and maintain, suggesting that this relationship is costly to the shrimps. This study was carried out using the facultatively symbiotic goby–shrimp interaction, because the obligate shrimp is known to stop burrowing activity without the symbiotic goby. Future investigation using obligately symbiotic goby might lead to different results from those of this study, because the more specialized mutualist gobies will provide greater services to the shrimps. Studying the ecology of both obligate and facultative associations would provide further insight into the evolution of goby–alpheid shrimp symbiosis. • Shrimps were kept with or without gobies in tanks. • In solitary treatment most burrow parameters positively correlated with shrimp size. • In symbiotic treatment burrow parameters did not correlate with shrimp size. • The results indicate that the shrimps incur a cost of the relationship. [ABSTRACT FROM AUTHOR]

The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is a pest of many economically important agricultural crops and a vector of plant viruses. Bemisia tabaci harbors facultative endosymbiont species that have been implicated in pest status, including tolerance to insecticides, virus transmission efficiency and tolerance to high-temperatures. The facultative endosymbionts reported in B. tabaci include Arsenophonus, Hamiltonella, Wolbachia, Cardinium, Fritschea and Rickettsia. We collected whitefly populations from weed and crop hosts in south Florida and identified the whitefly species as well as the facultative endosymbionts present in these populations by molecular analysis. In addition, a phylogenetic analysis of whiteflies and their endosymbionts was performed. The only facultative endosymbionts found among the B. tabaci populations collected in Florida were Hamiltonella and Rickettsia. The phylogenetic analysis revealed the low genetic diversity of whiteflies and their endosymbionts. Additionally, the phylogenetic tree clustered Rickettsia from Florida in the R1 genetic group. The results will aid to understand the role of the bacterial endosymbionts in the whitefly host. [ABSTRACT FROM AUTHOR]