Behavioral assumptions and management ability

The paper explores the consequences that relying on different behavioral assumptions intraining managers may have on their future performance. We argue that training with anemphasis on the standard assumptions used in economics (rationality and self-interest) is goodfor technical posts but may also lead future managers to rely excessively on rational and explicitsafeguarding, crowding out instinctive relational heuristics and signaling a bad human type topotential partners. In contrast, human assumptions used in management theories, because oftheir diverse, implicit and even contradictory nature, do not conflict with the innate set ofcooperative tools and may provide a good training ground for such tools. We present tentativeconfirmatory evidence by examining how the weight given to behavioral assumptions in the corecourses of the top 100 business schools influences the average salaries of their MBA graduates.Controlling for the self-selected average quality of their students and some other schools characteristics, average salaries are seen to be significantly greater for schools whose core MBAcourses contain a higher proportion of management courses as opposed to courses based oneconomics or technical disciplines.

Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae)

Influence of different tropical fruits on biological and behavioral aspects of the Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera, Tephritidae). Studies on Ceratitis capitata, a world fruit pest, can aid the implementation of control programs by determining the plants with higher vulnerability to attacks and plants able to sustain their population in areas of fly distribution. The objective of the present study was to evaluate the influence of eight tropical fruits on the following biological and behavioral parameters of C. capitata: emergence percentage, life cycle duration, adult size, egg production, longevity, fecundity, egg viability, and oviposition acceptance. The fruits tested were: acerola (Malpighia glabra L.), cashew (Anacardium occidentale L.), star fruit (Averrhoa carambola L.), guava (Psidium guajava L.), soursop (Annona muricata L.), yellow mombin (Spondias mombin L.), Malay apple (Syzygium malaccense L.), and umbu (Spondias tuberosa L.). The biological parameters were obtained by rearing the recently hatched larvae on each of the fruit kinds. Acceptance of fruits for oviposition experiment was assessed using no-choice tests, as couples were exposed to two pieces of the same fruit. The best performances were obtained with guava, soursop, and star fruit. Larvae reared on cashew and acerola fruits had regular performances. No adults emerged from yellow mombin, Malay apple, or umbu. Fruit species did not affect adult longevity, female fecundity, or egg viability. Guava, soursop, and acerola were preferred for oviposition, followed by star fruit, Malay apple, cashew, and yellow mombin. Oviposition did not occur on umbu. In general, fruits with better larval development were also more accepted for oviposition.

Behavioral ecology of Heteragrion consors Hagen (Odonata, Megapodagrionidae): a shade-seek Atlantic forest damselfly

Behavioral ecology of Heteragrion consors Hagen (Odonata: Megapodagrionidae): a shade-seek Atlantic forest damselfly. The intensity of the inter and intra-sexual selection can affect male behavioral traits as territorial fidelity and aggressiveness allowing the existence of different strategies. However, its differential success could be affected by environmental - as the diel variation in temperature - and physiological constrains - as the variation in thermoregulatory abilities. In this context, we present a behavioral analysis of Heteragrion consors (Zygoptera, Megapodagrionidae) trying to characterize its mating system, diel activity pattern, temporal budget, territoriality and reproductive biology. These data were obtained based on field observations using the focal individual method and mark-recapture techniques in 120 m of a shaded Atlantic Forest stream in Brazil. The males of this species were territorial, varying in its local fidelity, while the females appear sporadically. Males were perched in the majority of the time, but were also observed in cleaning movements, longitudinal abdominal flexion, wing flexion and sperm transfer during perch. The males presented a perched thermoregulatory behavior related to an exothermic regulation. Foraging and agonistic interactions were rare, but dominate the other behavioral activities. Abdominal movements associated to long lasting copula pointed to the existence of sperm competition in this species. Males performed contact post-copulatory guarding of the females. These observations pointed to a non-resource mating system for this species.

Primate adult brain cell autotransplantation produces behavioral and biological recovery in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced parkinsonian St. Kitts monkeys.

The potential for "replacement cells" to restore function in Parkinson's disease has been widely reported over the past 3 decades, rejuvenating the central nervous system rather than just relieving symptoms. Most such experiments have used fetal or embryonic sources that may induce immunological rejection and generate ethical concerns. Autologous sources, in which the cells to be implanted are derived from recipients' own cells after reprogramming to stem cells, direct genetic modifications, or epigenetic modifications in culture, could eliminate many of these problems. In a previous study on autologous brain cell transplantation, we demonstrated that adult monkey brain cells, obtained from cortical biopsies and kept in culture for 7 weeks, exhibited potential as a method of brain repair after low doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) caused dopaminergic cell death. The present study exposed monkeys to higher MPTP doses to produce significant parkinsonism and behavioral impairments. Cerebral cortical cells were biopsied from the animals, held in culture for 7 weeks to create an autologous neural cell "ecosystem" and reimplanted bilaterally into the striatum of the same six donor monkeys. These cells expressed neuroectodermal and progenitor markers such as nestin, doublecortin, GFAP, neurofilament, and vimentin. Five to six months after reimplantation, histological analysis with the dye PKH67 and unbiased stereology showed that reimplanted cells survived, migrated bilaterally throughout the striatum, and seemed to exert a neurorestorative effect. More tyrosine hydroxylase-immunoreactive neurons and significant behavioral improvement followed reimplantation of cultured autologous neural cells as a result of unknown trophic factors released by the grafts. J. Comp. Neurol. 522:2729-2740, 2014. © 2014 Wiley Periodicals, Inc.

Nest plasticity of Cornitermes silvestrii (Isoptera, Termitidae, Syntermitinae) in response to flood pulse in the Pantanal, Mato Grosso, Brazil

Nest plasticity of Cornitermes silvestrii (Isoptera, Termitidae, Syntermitinae) in response to flood pulse in the Pantanal, Mato Grosso, Brazil. The Pantanal is one of the largest wetlands in the world. Since many areas in Pantanal are flooded during part of the year, it is expected that plants and animals would have mechanisms for their survival during the flooded period. This study investigated the existence of differences in nest shape and inquilines of Cornitermes silvestrii in areas influenced by the flood pulse. We measured the volume, height, width, and height/width ratio of 32 nests in flooded areas and 27 in dry areas, and performed an one-way-Anova with the quasi-Poisson distribution to determine if there were differences in the nest measurements between the points. To analyze the relationship of nest inquilines to flood pulse and nest shape, we performed a regression with a Poisson distribution with the inquiline richness and flood pulse, and the above measurements. The nests of C. silvestrii in flooded areas were significantly higher than nests in dry areas, and had a larger height/width ratio. Colonies in periodically flooded areas would probably make a larger effort to extend their nests vertically, to maintain at least some portion of the structure out of the water and prevent the entire colony from being submerged. Neither the size of the nest nor the flood pulses influenced the assemblage of 11 species found in nests of C. silvestrii.

Evidence of phenotypic plasticity of larvae of Simulium subpallidum Lutz in different streams from the Brazilian Cerrado

In this paper, the overall morphological differences between populations of Simulium subpallidumLutz, 1909 are studied. Several studies found in the literature point to a relationship between the labral fans and body size and the habitat where blackfly larvae occur. However, other characteristics potentially related to the microhabitat, such as abdominal hook circlet morphology, which is used for larvae to fix themselves in the substratum, and thoracic prolegs morphology, which help larvae move in the substratum, were analyzed in three different populations of S. subpallidum, one of which occupied a faster flow. The results suggest phenotypic plasticity in S. subpallidum and a tendency toward larger structures in faster flows.

A behavioral ecology of shermen: hidden stories from trajectory data in the Northern Humboldt Current System

This work proposes an original contribution to the understanding of shermen spatial behavior, based on the behavioral ecology and movement ecology paradigms. Through the analysis of Vessel Monitoring System (VMS) data, we characterized the spatial behavior of Peruvian anchovy shermen at di erent scales: (1) the behavioral modes within shing trips (i.e., searching, shing and cruising); (2) the behavioral patterns among shing trips; (3) the behavioral patterns by shing season conditioned by ecosystem scenarios; and (4) the computation of maps of anchovy presence proxy from the spatial patterns of behavioral mode positions. At the rst scale considered, we compared several Markovian (hidden Markov and semi-Markov models) and discriminative models (random forests, support vector machines and arti cial neural networks) for inferring the behavioral modes associated with VMS tracks. The models were trained under a supervised setting and validated using tracks for which behavioral modes were known (from on-board observers records). Hidden semi-Markov models performed better, and were retained for inferring the behavioral modes on the entire VMS dataset. At the second scale considered, each shing trip was characterized by several features, including the time spent within each behavioral mode. Using a clustering analysis, shing trip patterns were classi ed into groups associated to management zones, eet segments and skippers' personalities. At the third scale considered, we analyzed how ecological conditions shaped shermen behavior. By means of co-inertia analyses, we found signi cant associations between shermen, anchovy and environmental spatial dynamics, and shermen behavioral responses were characterized according to contrasted environmental scenarios. At the fourth scale considered, we investigated whether the spatial behavior of shermen re ected to some extent the spatial distribution of anchovy. Finally, this work provides a wider view of shermen behavior: shermen are not only economic agents, but they are also foragers, constrained by ecosystem variability. To conclude, we discuss how these ndings may be of importance for sheries management, collective behavior analyses and end-to-end models.

Plasticity of lifespan: a reaction norm perspective.

It is a well-appreciated fact that in many organisms the process of ageing reacts highly plastically, so that lifespan increases or decreases when the environment changes. The perhaps best-known example of such lifespan plasticity is dietary restriction (DR), a phenomenon whereby reduced food intake without malnutrition extends lifespan (typically at the expense of reduced fecundity) and which has been documented in numerous species, from invertebrates to mammals. For the evolutionary biologist, DR and other cases of lifespan plasticity are examples of a more general phenomenon called phenotypic plasticity, the ability of a single genotype to produce different phenotypes (e.g. lifespan) in response to changes in the environment (e.g. changes in diet). To analyse phenotypic plasticity, evolutionary biologists (and epidemiologists) often use a conceptual and statistical framework based on reaction norms (genotype-specific response curves) and genotype × environment interactions (G × E; differences in the plastic response among genotypes), concepts that biologists who are working on molecular aspects of ageing are usually not familiar with. Here I briefly discuss what has been learned about lifespan plasticity or, more generally, about plasticity of somatic maintenance and survival ability. In particular, I argue that adopting the conceptual framework of reaction norms and G × E interactions, as used by evolutionary biologists, is crucially important for our understanding of the mechanisms underlying DR and other forms of lifespan or survival plasticity.

Empfehlungen zur Diagnostik und Therapie der behavioralen und psychologischen Symptome der Demenz (BPSD) [Recommendations for diagnosis and therapy of behavioral and psychological symptoms in dementia (BPSD)].

In patients with dementia, Behavioral and Psychological Symptoms of Dementia (BPSD) are frequent findings that accompany deficits caused by cognitive impairment and thus complicate diagnostics, therapy and care. BPSD are a burden both for affected individuals as well as care-givers, and represent a significant challenge for therapy of a patient population with high degree of multi-morbidity. The goal of this therapy-guideline issued by swiss professional associations is to present guidance regarding therapy of BPSD as attendant symptoms in dementia, based on evidence as well as clinical experience. Here it appears to be of particular importance to take into account professional experience, as at this point for most therapeutic options no sufficiently controlled clinical trials are available. A critical discussion of pharmaco-therapeutic intervention is necessary, as this patient-population is particularly vulnerable for medication side-effects. Finally, a particular emphasis is placed on incorporating and systematically reporting psycho-social and nursing options therapeutic intervention.

New insights into the role of microRNAs in pancreatic ß-cell maturation and plasticity

Le diabète est une maladie chronique caractérisée par une élévation du taux de sucre dans le sang aussi appelé « glycémie » reflétant un état pathologique. L'élévation de la glycémie au long cours a des répercussions délétères sur nombreux de nos tissus et organes d'où l'apparition de complications sévères chez les sujets diabétiques pouvant atteindre les yeux, les reins, le système nerveux, le système cardiovasculaire et les membres inférieurs. La carence en une hormone essentielle à notre organisme, l'insuline, est au coeur du développement de la maladie. L'insuline induit la captation du glucose circulant dans le sang en excès suite à une prise alimentaire riche en glucides et favorise son utilisation et éventuellement son stockage dans les tissus tels que le foie, le tissu adipeux et les muscles. Ainsi, l'insuline est vitale pour réguler et maintenir stable notre niveau de glycémie. Les cellules bêta du pancréas sont les seules entités de notre corps capables de produire de l'insuline et une perte de fonctionnalité associée à leur destruction ont été mises en cause dans le processus pathologique du diabète de type 2. Cependant la pleine fonctionnalité et la maturation des cellules bêta n'apparaissent qu'après la naissance lorsque le pancréas en développement a atteint sa masse adulte définitive. Enfin, une fois la masse des cellules bêta définitive établie, leur nombre et volume restent relativement constants au cours de la vie adulte chez un sujet sain. Néanmoins, au cours de périodes critiques les besoins en insuline sont augmentés tel qu'observé chez les femmes enceintes et les personnes obèses qui ont une perte de sensibilité à l'insuline qui se traduit par la nécessité de sécréter plus d'insuline afin de maintenir une glycémie normale. Dans l'hypothèse où la compensation n'a pas lieu ou n'est pas aboutie, le diabète se développe. Le processus de maturation postnatale ainsi que les événements compensatoires sont donc des étapes essentielles et de nombreuses questions sont encore non résolues concernant l'identification des mécanismes les régulant. Parmi les acteurs potentiels figurent de petites molécules d'ARN découvertes récemment appelées microARNs et qui ont été rapidement suggérées très prometteuses dans l'identification de nouvelles cibles thérapeutiques dans le cadre du diabète et d'autres pathologies. Les microARNs vont réguler l'expression de notre génome sans en modifier la séquence, phénomène également appelé épigénétique, ce qui résulte en des différences de comportement et de fonction cellulaires. Les microARNs sont donc susceptibles de jouer un rôle clé dans l'ensemble des processus biologiques et notre environnement associé à nos prédispositions génétiques peuvent grandement modifier leur niveau et donc leur action, qui à son tour se répercutera sur notre état physiologique. En effet nous avons identifié des changements de microARNs dans les cellules d'îlots pancréatiques de modèles animaux (rats et souris) associés à un état de résistance à l'insuline (grossesse et obésité). Par le biais d'expériences in vitro sur des cellules bêta extraites de rats et conservées en culture, nous avons pu analyser de plus près l'implication des microARNs dans la capacité des cellules bêta à sécréter de l'insuline mais aussi à se multiplier et à survivre au sein d'un environnement toxique. Ainsi, nous avons identifié des microARNs qui participent positivement à la compensation des cellules bêta, sous la direction d'hormones telles les estrogènes ou d'une hormone libérée par l'intestin au cours de la digestion (l'inerétine GLP1) et qui est largement utilisée comme agent thérapeutique dans la médication contre le diabète. Dans un second temps nous avons utilisé une stratégie similaire afin de déterminer le rôle de microARNs préalablement détectés comme étant changés au cours du développement postnatal des cellules bêta chez le rat. Cette étude a également mené à l'identification de microARNs participant à la maturation et à l'expansion de la masse des cellules bêta sous l'influence de la composition du régime alimentaire et des besoins en insuline adéquats qui en dépendent. Ces études apportent la vision de nouveaux mécanismes moléculaires impliquant les microARNs et démontrant leur importance pour le bon fonctionnement des cellules bêta et leur capacité d'adaptation à l'environnement. -- Les cellules bêta sont une composante des îlots pancréatiques de Langerhans et sont des cellules hautement différenciées qui ont l'unique capacité de sécréter de l'insuline sous l'influence des nutriments suite à une prise alimentaire. L'insuline facilite l'incorporation de glucose dans ses tissus cibles tels le foie, le tissu adipeux et les muscles. Bien que les besoins en insuline soient relativement constants au cours de la vie d'un individu sain, certaines conditions associées à un état de résistance à l'insuline, telles la grossesse ou l'obésité, requièrent une libération d'insuline majorée. En cas de résistance à l'insuline, une dysfonction des cellules bêta plus ou moins associée à leur mort cellulaire, conduisent à une sécrétion d'insuline insuffisante et au développement d'une hyperglycémie chronique, caractéristique du diabète de type 2. Jusqu'à présent, les mécanismes moléculaires sous- jacents à la compensation des cellules bêta ou encore menant à leur dysfonction restent peu connus. Découverts récemment, les petits ARNs non-codant appelés microARNs (miARNs), suscitent un intérêt grandissant de par leur potentiel thérapeutique pour la prise en charge et le traitement du diabète. Les miARNs sont de puissants régulateurs de l'expression génique qui lient directement le 3'UTR de leurs ARN messagers cibles afin d'inhiber leur traduction ou d'induire leur dégradation, ce qui leur permet de contrôler des fonctions biologiques multiples. Ainsi, nous avons pris pour hypothèse que les miARNs pourraient jouer un rôle essentiel en maintenant la fonction des cellules bêta et des processus compensatoires afin de prévenir le développement du diabète. Lors d'une première étude, une analyse transcriptomique a permis l'identification de miARNs différemment exprimés au sein d'îlots pancréatiques de rattes gestantes. Parmi eux, le miR-338-3p a démontré la capacité de promouvoir la prolifération et la survie des cellules bêta exposées à des acides gras saturés et des cytokines pro-inflammatoires, sans altérer leur propriété sécrétrice d'insuline. Nous avons également identifié deux hormones reconnues pour leurs propriétés bénéfiques pour la physiologie de la cellule bêta, l'estradiol et l'incrétine GLP1, qui régulent les niveaux du miR-338-3p. Ce miARN intègre parfaitement les voies de signalisation de ces deux hormones dépendantes de l'AMP cyclique, afin de contrôler l'expression de nombreux gènes conduisant à son action biologique. Dans un projet ultérieur, notre objectif était de déterminer la contribution de miARNs dans l'acquisition de l'identité fonctionnelle des cellules bêta en période postnatale. En effet, directement après la naissance les cellules bêta sont reconnues pour être encore immatures et incapables de sécréter de l'insuline spécifiquement en réponse à l'élévation de la glycémie. Au contraire, la réponse insulinique induite par les acides aminés ainsi que la biosynthèse d'insuline sont déjà fonctionnelles. Nos recherches ont permis de montrer que les changements de miARNs corrélés avec l'apparition du phénotype sécrétoire en réponse au glucose, sont régis par la composition nutritionnelle du régime alimentaire et des besoins en insuline qui en découlent. En parallèle, le taux de prolifération des cellules bêta est considérablement réduit. Les miARNs que nous avons étudiés coordonnent des changements d'expression de gènes clés impliqués dans l'acquisition de propriétés vitales de la cellule bêta et dans la maintenancé de son identité propre. Enfin, ces études ont permis de clairement démontrer l'importance des miARNs dans la régulation de la fonction des cellules bêta pancréatiques. -- Beta-cells are highly differentiated cells localized in the pancreatic islets and are characterized by the unique property of secreting insulin in response to nutrient stimulation after meal intake. Insulin is then in charge of facilitating glucose uptake by insulin target tissues such as liver, adipose tissue and muscles. Despite insulin needs stay more or less constant throughout life of healthy individuals, there are circumstances such as during pregnancy or obesity which are associated to insulin resistance, where insulin needs are increased. In this context, defects in beta-cell function, sometimes associated with beta-cell loss, may result in the release of inappropriate amounts of insulin leading to chronic hyperglycemia, properly defined as type 2 diabetes mellitus. So far, the mechanisms underlying beta- cell compensation as well as beta-cell failure remain to be established. The recently discovered small non-coding RNAs called microRNAs (miRNAs) are emerging as interesting therapeutic targets and are bringing new hope for the treatment of diabetes. miRNAs display a massive potential in regulating gene expression by directly binding to the 3'UTR of messenger RNAs and by inhibiting their translation and/or stability, enabling them to modify a wide range of biological functions. In view of this, we hypothesized that miRNAs may play an essential role in preserving the functional beta-cell mass and permitting to fight against beta-cell exhaustion and decompensation that can lead to diabetes development. In a first study, global profiling in pancreatic islets of pregnant rats, a model of insulin resistance, led to the identification of a set of differentially expressed miRNAs. Among them, miR-338- 3p was found to promote beta-cell proliferation and survival upon exposure of islet cells to pro- apoptotic stimuli such as saturated fatty acids or pro-inflammatory cytokines, without impairment in their capacity to release insulin. We also discovered that miR-338-3p changes are driven by two hormones, the estradiol and the incretin GLP1, both well known for their beneficial impact on beta- cell physiology. Consistently, we found that miR-338-3p integrates the cAMP-dependent signaling pathways regulated by these two hormones in order to control the expression of numerous genes and execute its biological functions. In a second project, we aimed at determining whether miRNAs contribute to the acquisition of beta-cell identity. Indeed, we confirmed that right after birth beta-cells are still immature and are unable to secrete insulin specifically in response to elevated concentrations of glucose. In contrast, amino acid-stimulated insulin release as well as insulin biosynthesis are already fully functional. In parallel, newborn beta-cells are proliferating intensively within the expanding pancreas. Interestingly, we demonstrated that the miRNA changes and the subsequent acquisition of glucose responsiveness is influenced by the diet composition and the resulting insulin needs. At the same time, beta-cell proliferation declines. The miRNAs that we have identified orchestrate expression changes of essential genes involved in the acquisition of specific beta-cell properties and in the maintenance of a mature beta-cell identity. Altogether, these studies clearly demonstrate that miRNAs play important roles in the regulation of beta-cell function.

The significant behavioral aspects of adopted children within successful adoption in Romania

The human behavior is giving the entire picture of a person. The behavior is based on a complex combination of personal innate factors, experience and education and the social network within which the individual is integrated. Each moment the complex individual factors face external and internal environmental aspects which in turn, generate proactive and retroactive reactions. The adoption process is an important and challenging social experiment, bringing to the adopted child a new affiliation, social network, experiences and educational standards. This comes in his/her life after the trauma of losing his biological affiliation and social and emotional support. Which are the significant characteristics of the adopted child's behavior? Which are the behavioral characteristics of the adoptive child that guarantee the success of the domestic adoptions in Romania? These are the questions we are going to answer here based on the research done within FISAN(6) project. The 32 children, 11-16 years old, adopted by Romanian families, during the early ages (0-4 years), were evaluated with complex evaluation tools for children and parents. The adoptive families participating in the research live in the Western counties of Romania.Successful adoption is defined as secure attachment of the adopted child. The conclusions emphasize the importance of: the pro-social behavior, the loving behavior showed to the parents, the assertive behavior, the differentiations between parents and people outside the family, and between the two parents, and the humor. These behaviors displayed by the adopted children are the ingredients of a successful integration within the adoptive family.

Consequences of genetic erosion on fitness and phenotypic plasticity in European tree frog populations (Hyla arborea).

The detrimental effects of genetic erosion on small isolated populations are widely recognized contrary to their interactions with environmental changes. The ability of genotypes to plastically respond to variability is probably essential for the persistence of these populations. Genetic erosion impact may be exacerbated if inbreeding affects plastic responses or if their maintenance were at higher phenotypic costs. To understand the interplay 'genetic erosion-fitness-phenotypic plasticity', we experimentally compared, in different environments, the larval performances and plastic responses to predation of European tree frogs (Hyla arborea) from isolated and connected populations. Tadpoles from isolated populations were less performant, but the traits affected were environmental dependant. Heterosis observed in crosses between isolated populations allowed attributing their low fitness to inbreeding. Phenotypic plasticity can be maintained in the face of genetic erosion as inducible defences in response to predator were identical in all populations. However, the higher survival and developmental costs for isolated populations in harsh conditions may lead to an additional fitness loss for isolated populations.

Spatio-temporal Brain Dynamics Mediating Post-error Behavioral Adjustments.

Optimal behavior relies on flexible adaptation to environmental requirements, notably based on the detection of errors. The impact of error detection on subsequent behavior typically manifests as a slowing down of RTs following errors. Precisely how errors impact the processing of subsequent stimuli and in turn shape behavior remains unresolved. To address these questions, we used an auditory spatial go/no-go task where continual feedback informed participants of whether they were too slow. We contrasted auditory-evoked potentials to left-lateralized go and right no-go stimuli as a function of performance on the preceding go stimuli, generating a 2 × 2 design with "preceding performance" (fast hit [FH], slow hit [SH]) and stimulus type (go, no-go) as within-subject factors. SH trials yielded SH trials on the following trials more often than did FHs, supporting our assumption that SHs engaged effects similar to errors. Electrophysiologically, auditory-evoked potentials modulated topographically as a function of preceding performance 80-110 msec poststimulus onset and then as a function of stimulus type at 110-140 msec, indicative of changes in the underlying brain networks. Source estimations revealed a stronger activity of prefrontal regions to stimuli after successful than error trials, followed by a stronger response of parietal areas to the no-go than go stimuli. We interpret these results in terms of a shift from a fast automatic to a slow controlled form of inhibitory control induced by the detection of errors, manifesting during low-level integration of task-relevant features of subsequent stimuli, which in turn influences response speed.

Phenotypic plasticity in the Caribbean sponge Callyspongia vaginalis (Porifera: Haplosclerida)

Sponge morphological plasticity has been a long-standing source of taxonomic difficulty. In the Caribbean, several morphotypes of the sponge Callyspongia vaginalis have been observed. To determine the taxonomic status of three of these morphotypes and their relationship with the congeneric species C. plicifera and C. fallax, we compared the spicule composition, spongin fiber skeleton and sequenced fragments of the mitochondrial genes 16S and COI and nuclear genes 28S and 18S ribosomal RNA. Phylogenetic analyses with ribosomal markers 18S and 28S rRNA confirmed the position of our sequences within the Callyspongiidae. None of the genetic markers provided evidence for consistent differentiation among the three morphotypes of C. vaginalis and C. fallax, and only C. plicifera stood as a distinct species. The 16S mtDNA gene was the most variable molecular marker for this group, presenting a nucleotide variability (π = 0.024) higher than that reported for COI. Unlike recent studies for other sponge genera, our results indicate that species in the genus Callyspongia maintain a high degree of phenotypic plasticity, and that morphological characteristics may not reflect reproductive boundaries in C. vaginalis.