Wood resistance of Magonia pubescens (Sapindaceae), Dalbergia nigra, and Machaerium amplum (Fabaceae) to Nasutitermes sp. (Blattodea: Termitidae).

Termites of the genus Nasutitermes sp. (Blattodea: Termitidae), which feed on cellulose, may cause wood to become brittle and fragile. This study aimed to evaluate the natural resistance of three native wood species: Magonia pubescens (Sapindaceae), Dalbergia nigra and Machaerium amplum (Fabaceae) to attack by Nasutitermes sp. termites and to investigate the relationship between resistance, extractive content, and oven-dry density. Samples of each wood species were subjected to a forced feeding process with Nasutitermes sp. termites for 30 days. Following the exposure, the oven-dry density, extractive content, percentage of wood loss, and termite mortality were determined for each sample. Dalbergia nigra exhibited resistance to termite attack and had the highest extractive content at 13.14%. Conversely, M. amplum had the highest wood loss at 5.37% and the lowest extractive content at 1.94%. Both species showed a negative correlation between wood loss and extractive content, but no correlation with wood density. Magonia pubescens had the highest density at 0.90 g/cm3. Macherium amplum and M. pubescens caused 100% termite mortality, while D. nigra caused 40% mortality.

Intermittent access to sugary drinks associated with fasting induces overeating and depressive-like behavior in female C57BL/6J mice.

Binge eating disorder is the most prevalent eating disorder, affecting both sexes but more commonly found in women. Given the frequent co-occurrence of psychiatric disorders, this study aimed to establish a standardized experimental intermittent protocol to investigate overeating associated with depression. A 10-day protocol induced uncontrolled eating behavior in C57BL/6J female mice. The first experiment included the following groups: naive group (chow ad libitum), control group (chow and sucrose solution ad libitum), and fasting groups (16 and 20 h) exposed to an intermittent sucrose solution (10 %) and chow regimen. Subsequently, the feeding test, open field test, elevated plus maze test, tail suspension test, and light/dark conflict test were conducted. Furthermore, monoamine oxidase (MAO) A and B activities in brain structures and plasma corticosterone levels were assessed. Food overconsumption and depressive-like behavior were observed in both sucrose fasting groups, while risk-taking behaviors were specifically observed in the 20-hour fasting sucrose group. While both fasting sucrose groups caused reduced hippocampal MAO-A activity, only the F20 sucrose group inhibited MAO-B in the cortex and hypothalamus. Moreover, both fasting sucrose groups exhibited elevated corticosterone levels. In a separate design (Experiment 2), groups with 16 and 20 h of fasting alone (without sucrose) did not show the same behavioral results as the intermittent fasting sucrose groups, thus avoiding fasting bias. Based on these results, the 20-hour sucrose fasting group was chosen as the ideal protocol for mimicking overeating behavior associated with depression to investigate future therapeutic approaches for this comorbidity.

Dietary counseling, meal patterns, and diet quality in patients with type 2 diabetes mellitus with/without chronic kidney disease.

BACKGROUND: Aim to this study is to investigate the association of Dietary Counseling, Meal Patterns, and Diet Quality (DietQ) in Patients with Type 2 Diabetes Mellitus (T2DM) with/without chronic kidney disease (CKD) in primary healthcare. METHODS: Cross-sectional study acquired data on dietary counseling and meal patterns by direct interview with a food-frequency questionnaire and one 24-h food-recall. The Healthy Eating Index (HEI) was used to classify DietQ ["good" DietQ (GDietQ, score ≥ 80) and "poor" DietQ (PDietQ, score < 80)]. PARTICIPANTS/SETTING: This study included 705 patients with T2DM: 306 with normal kidney function; 236 with early nephropathy, and 163 with overt nephropathy (ON). STATISTICAL ANALYSES PERFORMED: Multivariate linear-regression models for predicting HEI and χ2 tests for qualitative variables and one-way ANOVA for quantitative variables were employed. Mann-Whitney U and independent Student t were performed for comparisons between GDietQ and PDietQ. RESULTS: Only 18 % of the population was classified as GDietQ. Patients with ON and PDietQ vs. with GDietQ received significantly less dietary counseling from any health professional in general (45 % vs 72 %, respectively), or from any nutrition professional (36 % vs. 61 %, respectively). A better HEI was significantly predicted (F = 42.01; p = 0.0001) by lower HbA1C (ß -0.53, p = 0.0007) and better diet diversity (ß 8.09, p = 0.0001). CONCLUSIONS: Patients with more advanced stages of CKD had less nutritional counseling and worse dietary patterns, as well as more frequent PDietQ. Our findings reinforce the need for dietitians and nutritionists in primary healthcare to provide timely nutritional counseling.

You are what you eat: a systematic review exploring the interaction between Brazilian sand flies and their vertebrate food sources.

Sand flies play a crucial role as vectors of bacteria, viruses, and protists, with Leishmania being the most notable among them, transmitted to vertebrate hosts during blood feeding. Understanding the feeding behaviours of sand flies is imperative for gaining insights into their eco-epidemiological roles in the transmission of these infectious agents. This systematic review aimed to answer the question 'What are the blood-feeding sources identified in Brazilian sand flies?' to provide an analysis of their blood-feeding habits. The diverse range of at least 16 vertebrate orders identified as blood sources for 54 sand fly species across different geographic regions was summarised, and the factors potentially associated with the risk of bias in the included studies were analysed. The findings broaden the discussion concerning methods used to identify blood meal sources and shed light on the implications of sand fly feeding behaviours for the transmission dynamics of Leishmania.

Sugar-conditioned honey bees can be biased towards a nectarless dioecious crop.

The targeted pollination strategy has shown positive results in directing honey bees to crop flowers offering nectar along with pollen as reward. Kiwifruit is a functionally dioecious species, which relies on bees to transport pollen from staminate to pistillate nectarless flowers. Following the targeted pollination procedures recently validated, we first developed a mimic odor (KM) based on kiwifruit floral volatiles for which bees showed the highest level of generalization to the natural floral scent, although the response towards pistillate flowers was higher than towards staminate flowers. Then, in the field, feeding colonies KM-scented sucrose solution resulted in higher amounts of kiwifruit pollen collected by honey bees compared to control colonies fed unscented sucrose solution. Our results support the hypothesis that olfactory conditioning bees biases their foraging preferences in a nectarless crop, given the higher visitation to target flowers despite having provided the mimic odor paired with a sugar reward.

Bite hard: Linking cranial loading mechanics to ecological differences in gnawing behavior in caviomorph rodents.

The mammalian skull is very malleable and has notably radiated into highly diverse morphologies, fulfilling a broad range of functional needs. Although gnawing is relatively common in mammals, this behavior and its associated morphology are diagnostic features for rodents. These animals possess a very versatile and highly mechanically advantageous masticatory apparatus, which, for instance, allowed caviomorph rodents to colonize South America during the Mid-Eocene and successfully radiate in over 200 extant species throughout most continental niches. Previous work has shown that differences in bite force within caviomorphs could be better explained by changes in muscle development than in mechanical advantages (i.e., in cranial overall morphology). Considering the strong bites they apply, it is interesting to assess how the reaction forces upon the incisors (compression) and the powerful adductor musculature pulling (tension) mechanically affect the cranium, especially between species with different ecologies (e.g., chisel-tooth digging). Thus, we ran finite element analyses upon crania of the subterranean Talas' tuco-tuco Ctenomys talarum, the semi-fossorial common degu Octodon degus, and the saxicolous long-tailed chinchilla Chinchilla lanigera to simulate: (A) in vivo biting in all species, and (B) rescaled muscle forces in non-ctenomyid rodents to match those of the tuco-tuco. Results show that the stress patterns correlate with the mechanical demands of distinctive ecologies, on in vivo-based simulations, with the subterranean tuco-tuco being the most stressed species. In contrast, when standardizing all three species (rescaled models), non-ctenomyid models exhibited a several-fold increase in stress, in both magnitude and affected areas. Detailed observations evidenced that this increase in stress was higher in lateral sections of the snout and, mainly, the zygomatic arch; between approximately 2.5-3.5 times in the common degu and 4.0-5.0 times in the long-tailed chinchilla. Yet, neither species, module, nor simulation condition presented load factor levels that would imply structural failure by strong, incidental biting. Our results let us conclude that caviomorphs have a high baseline for mechanical strength of the cranium because of the inheritance of a very robust "rodent" model, while interspecific differences are associated with particular masticatory habits and the concomitant level of development of the adductor musculature. Especially, the masseteric and zygomaticomandibular muscles contribute to >80% of the bite force, and therefore, their contraction is responsible for the highest strains upon their origin sites, that is, the zygomatic arch and the snout. Thus, the robust crania of the subterranean and highly aggressive tuco-tucos allow them to withstand much stronger forces than degus or chinchillas, such as the ones produced by their hypertrophied jaw adductor muscles or imparted by the soil reaction.

Sisvan food intake markers from six to 23 months: critical analysis and validation.

OBJECTIVE: To explore the internal structure and analyze evidence of measurement invariance of the Sisvan form of food intake markers of the Food and Nutrition Surveillance System (Sisvan) for children aged six to 23 months. METHODS: Sisvan microdata from 2015 to 2019 were used. After analyzing sample adequacy, exploratory factor analysis was carried out considering factor loadings (≥ 0.30 and < 0.85), communality (> 0.20), model fit indices - Tucker-Lewis index (TLI) > 0.90, and root mean square error of approximation (RMSEA) < 0.08. A critical analysis of the form items was performed to adjust the parameters. Measurement stability was investigated between age groups, macro-regions and longitudinally by multi-group confirmatory factor analysis in configural, metric, and scalar invariance models. Configural invariance was accepted if RMSEA < 0.08 and TLI and comparative fit index (CFI) > 0.90. Metric and scalar invariances were accepted if ΔRMSEA < 0.015 and ΔCFI < 0.01, compared to the previous model. RESULTS: After critical analysis, items were grouped (vegetables and leafy greens; meat or eggs and liver) and excluded (salty food; porridge with milk; rice, potatoes, yams, cassava, flour, or pasta). The exploratory model comprised three factors: healthy complementary feeding (fruit; vegetables; orange or dark green leafy vegetables or fruits; meat, offal, or egg; beans), ultra-processed (yogurt; hamburger and/or sausages; sweetened drinks; instant noodles, packet snacks, or salty cookies; sandwich cookies, sweets, or treats), and milk feeding (breast milk; other milk), with satisfactory factor loadings, communalities and fit (TLI: 0.918, RMSEA: 0.071). The reformulated instrument was stable in the invariance models tested. CONCLUSIONS: With the incorporation of the modifications to the Sisvan form, the food intake markers subsidize a more adequate interpretation of the feeding situation of children aged six to 23 months.

Diet and between-tissue isotope comparisons reveal different foraging strategies for age and sex of a Saffron Finch (Sicalis flaveola Linnaeus, 1766) population.

Measuring stable isotopes in different tissues offers the opportunity to provide insight into the foraging ecology of a species. This study aimed to assess how diet varies between yellow females, yellow males, and dull individuals of a Saffron Finch (Sicalis flaveola) population. We measured δ13C and δ15N in blood over a year, and in different feathers, to estimate seasonal consistency of resource use for each category. We conducted this study in a private farm in the Central Brazilian savannas. We sampled 195 individuals in seven field samplings between January 2017 and March 2018. The mean blood δ13C values were similar among yellow females, yellow males and dull individuals, indicating that this population of Saffron Finch predominantly accesses similar resources throughout the year, with a predominant C4 signal. Although Saffron Finch is considered a granivorous species, the mean δ15N values found indicate that both adults and juveniles also incorporate in their tissues some invertebrate. The slight isotope-tissue difference between feathers and blood is similar to the reported in previous studies and may reflect tissue-to-tissue discrimination. The isotopic space of yellow males was greater than that of yellow females and dull individuals, indicating greater dietary diversity due to greater inter-individual variation in diet. In Saffron Finch, which delays plumage maturation, competition-driven partitioning of food resources seems essential in driving carotenoid-based plumage coloration between age classes and sexes.

LEAP2 is associated with impulsivity and reward sensitivity depending on the nutritional status and decreases with protein intake in humans.

AIM: Liver-expressed antimicrobial peptide 2 (LEAP2) dynamics in human plasma and its association with feeding behaviour remain poorly understood. Therefore, this study aims: (a) to investigate fasting LEAP2 in participants with normal weight or with overweight or mild obesity (OW/OB); (b) to study the association between fasting LEAP2 and anthropometric and metabolic traits, feeding behaviour, LEAP2 genetic variants and blood cell DNA methylation status; and (c) to ascertain postprandial changes in LEAP2 after high protein intake and the association with feeding behaviour and food intake. METHODS: Anthropometric and behavioural measures, genotyping, methylation profiling, plasma glucose and LEAP2 concentrations were assessed in 327 females and males. A subgroup of 123 participants received an ad libitum high-protein meal, and postprandial LEAP2 concentration and behavioural measures were assessed. RESULTS: LEAP2 concentration was higher in participants with OW/OB (p < 0.001) and in females (p < 0.001), and was associated with LEAP2 single nucleotide polymorphisms rs765760 (p = 0.012) and rs803223 (p = 0.019), but not with LEAP2 methylation status. LEAP2 concentration was directly related to glycaemia (p = 0.001) and fullness (p = 0.003) in participants with normal weight, whereas it was associated with body mass index (p = 0.018), waist circumference (p = 0.014) and motor impulsivity in participants with OW/OB (p = 0.005). A negative association with reward responsiveness was observed in participants with OW/OB (p = 0.023). LEAP2 concentration was inversely associated with food intake (p = 0.034) and decreased after a high-protein meal (p < 0.001), particularly in women (p = 0.002). CONCLUSION: Increased LEAP2 in participants with OW/OB is associated with behavioural characteristics of obesity. Our results show sexual dimorphism in LEAP2 concentration before and after food intake and highlight the role of LEAP2 in feeding regulation.

Menopause and metabolic syndrome: anthropometric, lipid, and dietary profiles.

OBJECTIVE: The aim of this study was to characterize the anthropometric, lipid, and dietary profiles of postmenopausal women with metabolic syndrome attending a public health service and compare them with a group of women without metabolic syndrome. METHODS: A cross-sectional study was conducted with 60 postmenopausal women who were divided into two groups: control group and metabolic syndrome group, attending the Climacteric Outpatient Clinic at Santa Casa de São Paulo Hospital, Brazil, between February 2019 and December 2021. Participants were evaluated using a validated semi-quantitative food frequency questionnaire, body mass index, waist circumference, and serum laboratory tests. RESULTS: Significant differences were observed between the groups regarding body mass index and all parameters of metabolic syndrome. The nutritional profile revealed an imbalance in the number of food portions consumed, particularly in the intake of carbohydrates in the form of flour and sweets, which was higher in the metabolic syndrome group. CONCLUSION: The analysis of the three profiles of postmenopausal women revealed significant imbalances, particularly in the metabolic syndrome group, highlighting the importance of regular adjustments and evaluations during this phase of a woman's life.

Food consumption, physical activity and aerobic capacity in systemic lupus erythematosus patients with high cardiovascular risk.

Systemic Lupus Erythematosus (SLE) is a chronic, autoimmune and multisystemic rheumatic disease. Patients with SLE have decreased functional and aerobic capacity, as well as increased prevalence of Cardiovascular Diseases (CVD), which are the primary causes of morbimortality in this condition. Dietary intake and physical activity are well-known modifiable cardiovascular risk factors. The aim of this study is to describe food consumption, sedentary behavior, physical activity level, and functional and aerobic capacity in a sample of SLE patients with high cardiovascular risk. This was a cross-sectional study in which patients were assessed for (i) Demographic, anthropometric, and disease-related parameters; (ii) Food consumption; (iii) Physical activity level and sedentary behavior; (iv) Functional and aerobic capacity. Patients averaged 41.7 ± 9 years, and most were classified as overweight/obese (87%). Average macronutrient intake was within recommendations; however, fiber (16 ± 9g) and calcium (391 ± 217 mg) intakes were below, and sodium intake (2.9 ± 1.3 mg) was above recommendations. Besides, food consumption assessed by the Nova system showed a predominance of unprocessed foods (43.8 ± 14.0%TEI), although ultraprocessed food intake (20.0 ± 13.9%TEI) was slightly higher than that seen in the Brazilian population. Patients also exhibited high sedentary behavior (8.2 ± 2.2h) and only eighteen participants reached the minimum recommended amount of moderate-to-vigorous physical activity. Overall, patients had a low functional and aerobic capacity compared to the general population. Data from this study may help design dedicated clinical trials aiming to investigate the effects of lifestyle intervention to mitigate CVD in SLE.

Relación entre la percepción de condición física y medidas antropométricas auto reportadas en estudiantes universitarios / Relationship between perceived physical fitness and self-reported anthropometric measures in university students / Relação entre percepção de condicionamento físico e medidas antropométricas autorreferidas em estudantes universitários

La percepción de la condición física en estudiantes universitarios se refiere a cómo se ven a sí mismos en términos de su estado físico y salud. En esta etapa, las variables antropométricas pueden verse afectadas por estrés, cambios en hábitos de sueño y alimentación, y menor participación en actividades físicas, impactando el desempeño académico y salud general. El objetivo fue relacionar la percepción de la condición física con medidas antropométricas auto reportadas en estudiantes universitarios Esta Investigación es de tipo descriptivo-correlacional, de diseño observacional y corte transversal. Fueron evaluados 46 estudiantes universitarios de la ciudad de Talca. La condición física se midió por medio del International Fitness Scale (IFIS) y las medidas antropométricas por medio de auto reporte. La condición física general se relacionó de manera inversa con la circunferencia de cintura (r=-0,32; p=0,028), la circunferencia de cintura(r=-0,44; p=0,002) y el ICE (r=-0,43; p=0,003). Se observaron correlaciones inversas entre la condición cardiorrespiratoria con el IMC (p=0,008; r=-0,38), circunferencia de cintura e ICE (p=0,008; r=-0,38). La velocidad/agilidad se correlacionó de forma inversa con el índice de masa corporal (IMC) (p=0,001; r=-0,46), circunferencia de cintura (p=0,019; r=-0,34), cadera (p= 0,004; r= -0,40) y el ICE (p=0,004; r=-0,41). La flexibilidad se correlaciono de forma inversa con el IMC (p=0,041; r=-0,30), circunferencia de cintura (p=0,023; r=-0,33), índice cintura cadera (ICC) (p= 0,001; r=-0,45)). Por último, la fuera muscular no se correlaciono con las variables antropométricas. Se concluye que existe correlación inversa entre la percepción de la condición física y algunos autore portes de las medidas antropométricas.

The physical fitness perception of college students refers to how they see themselves in terms of their physical condition and health. In this stage, anthropometric variables may be affected by stress, changes in sleep and eating habits, and decreased participation in physical activities, impacting academic performance and general health. The objective of this study is to relate the perception of physical condition with self-reported anthropometric measures in university students. This is a descriptive-correlational, observational, cross-sectional research. Forty-six university students from the city of Talca were evaluated. Physical condition was measured by means of the International Fitness Scale (IFIS) and anthropometric measures by means of self-report. General physical condition was inversely related to waist circumference (r=-0.32; p=0.028), waist circumference (r=-0.44; p=0.002) and IFIS (r=-0.43; p=0.003). Inverse correlations were observed between cardiorespiratory fitness with BMI (p=0.008; r=-0.38), waist circumference and ECI (p=0.008; r=-0.38). Speed/agility was inversely correlated with body mass index (BMI) (p=0.001; r=-0.46), waist circumference (p=0.019; r=-0.34), hip (p= 0.004; r= -0.40) and ECI (p=0.004; r=-0.41). Flexibility was inversely correlated with BMI (p=0.041; r=-0.30), waist circumference (p=0.023; r=-0.33), waist hip index (WHI) (p= 0.001; r=-0.45)). Lastly, muscle was not correlated with the anthropometric variables. It is concluded that there is an inverse correlation between the perception of physical condition and some anthropometric measures.

A percepção da aptidão física em estudantes universitários refere-se a como eles se veem em termos de sua condição física e saúde. Nessa fase, as variáveis antropométricas podem ser afetadas pelo estresse, por mudanças nos hábitos de sono e alimentação e pela diminuição da participação em atividades físicas, o que afeta o desempenho acadêmico e a saúde em geral. O objetivo foi relacionar a percepção da aptidão física com medidas antropométricas autorreferidas em estudantes universitários. Trata-se de uma pesquisa descritiva, correlacional, transversal e observacional. Foram avaliados 46 estudantes universitários da cidade de Talca. A condição física foi medida por meio da Escala Internacional de Aptidão Física (IFIS) e as medidas antropométricas por meio de autorrelato. A aptidão física geral foi inversamente relacionada à circunferência da cintura (r=-0,32; p=0,028), circunferência da cintura (r=-0,44; p=0,002) e IFIS (r=-0,43; p=0,003). Foram observadas correlações inversas entre a aptidão cardiorrespiratória com o IMC (p=0,008; r=-0,38), a circunferência da cintura e o ECI (p=0,008; r=-0,38). A velocidade/agilidade foi inversamente correlacionada com o índice de massa corporal (IMC) (p=0,001; r=-0,46), circunferência da cintura (p=0,019; r=-0,34), quadril (p= 0,004; r= -0,40) e ECI (p=0,004; r=-0,41). A flexibilidade foi inversamente correlacionada com o IMC (p=0,041; r=-0,30), a circunferência da cintura (p=0,023; r=-0,33), o índice cintura-quadril (WHI) (p= 0,001; r=-0,45). Por fim, a musculatura não foi correlacionada com as variáveis antropométricas. Concluise que há uma correlação inversa entre a percepção da condição física e algumas medidas antropométricas.

Foraging task specialization in honey bees (Apis mellifera): the contribution of floral rewards to the learning performance of pollen and nectar foragers.

Social insects live in communities where cooperative actions heavily rely on the individual cognitive abilities of their members. In the honey bee (Apis mellifera), the specialization in nectar or pollen collection is associated with variations in gustatory sensitivity, affecting both associative and non-associative learning. Gustatory sensitivity fluctuates as a function of changes in motivation for the specific floral resource throughout the foraging cycle, yet differences in learning between nectar and pollen foragers at the onset of food collection remain unexplored. Here, we examined nectar and pollen foragers captured upon arrival at food sources. We subjected them to an olfactory proboscis extension reflex (PER) conditioning using a 10% sucrose solution paired (S10%+P) or unpaired (S10%) with pollen as a co-reinforcement. For non-associative learning, we habituated foragers with S10%+P or S10%, followed by dishabituation tests with either a 50% sucrose solution paired (S50%+P) or unpaired (S50%) with pollen. Our results indicate that pollen foragers show lower performance than nectar foragers when conditioned with S10%. Interestingly, performance improves to levels similar to those of nectar foragers when pollen is included as a rewarding stimulus (S10%+P). In non-associative learning, pollen foragers tested with S10%+P displayed a lower degree of habituation than nectar foragers and a higher degree of dishabituation when pollen was used as the dishabituating stimulus (S10%+P). Altogether, our results support the idea that pollen and nectar honey bee foragers differ in their responsiveness to rewards, leading to inter-individual differences in learning that contribute to foraging specialization.

Endogenous Opioids in the Homeostatic Regulation of Hunger, Satiety, and Hedonic Eating: Neurobiological Foundations.

This chapter (part one of a trilogy) summarizes the neurobiological foundations of endogenous opioids in the regulation of energy balance and eating behavior, dysregulation of which translates to maladaptive dietary responses in individuals with obesity and eating disorders, including anorexia, bulimia, and binge eating disorder. Knowledge of these neurobiological foundations is vital to researchers' and clinicians' understanding of pathophysiology as well as the science-based development of multidisciplinary diagnoses and treatments for obesity and eating disorders. We highlight mechanisms of endogenous opioids in both homeostatic and hedonic feeding behavior, review research on the dysregulation of food reward that plays a role in a wide array of obesity and disordered eating, and the clinical implications of neurobiological responses to food for current science-based treatments for obesity and eating disorders.

Role of Endogenous Opioids in the Pathophysiology of Obesity and Eating Disorders.

This second chapter in our trilogy reviews and critically appraises the scientific evidence for the role of endogenous opioid system (EOS) activity in the onset and progression of both obesity and eating disorders. Defining features of normative eating and maladaptive eating behaviors are discussed as a foundation. We review the scientific literature pertaining to the predisposing risk factors and pathophysiology for obesity and eating disorders. Research targeting the association between obesity, disordered eating, and psychiatric comorbidities is reviewed. We conclude by discussing the involvement of endogenous opioids in neurobiological and behavior traits, and the clinical evidence for the role of the EOS in obesity and eating disorders.

Morphological description of the digestive tract of the Amazonian Diving Lizard Uranoscodon superciliosus (Linnaeus, 1758) and its associations to the diet and foraging mode.

The study aimed to characterize the digestive tract of Uranoscodon superciliosus and its associations to the diet and foraging behavior already described for the species. Five lizards were captured in forest areas near the city of Manaus, Amazonas, Brazil. Tongue, oesophagus, stomach, small and large intestines fragments were collected, fixed, and processed for light microscopy. Hyaline cartilage was present in the center of the tongue, and the papillae from the apex and glands from the radix showed positive reaction to Alcian blue. The oesophagus presented a folded mucosa, covered by an epithelium with mucous and goblet cells positive to PAS and Alcian blue. There was presence of gastric glands in the cardic and fundic stomach regions, plus all the regions reacted positively to PAS. Fold and villi variations in both small and large intestine were noted, as well as the number and arrangement of goblet cells. Mucous and goblet cells from the small intestine were positively stained in PAS, while only the goblet cells were Alcian blue positive. These findings indicate that the Amazonian Diving Lizard's digestive tract organs, mainly the tongue and stomach, present morphologies associated to ambush-type foraging and a specific diet largely based on small invertebrates.

Trophic plasticity of tetra-fish, Psalidodon aff. fasciatus (Cuvier, 1819) (Characidae), in an Atlantic Forest stream of Northeast Brazil.

Trophic plasticity is a distinctive feature of freshwater fishes, representing an essential strategy for fish living in resource-variable environments. We analyzed the stomach contents of individuals sampled in two Atlantic Forest streams to identify the primary food sources consumed by Psalidodon aff. fasciatus and verify the existence of spatial, seasonal, and ontogenetic variations. The diet was determined by analyzing the stomach contents using the Volume Method to quantify the importance of food items. In general, Psalidodon aff. fasciatus was classified as an omnivorous species, consuming mainly insects, plant material, and filamentous algae. The results also showed significant effects for all factors considered (spatial, seasonal, and ontogenetic). Finally, Psalidodon aff. fasciatus demonstrated considerable trophic plasticity, which can result in better use of available resources in the environment and improved resource partitioning, reducing intraspecific and interspecific competition.

Feeding efficiency of two coexisting nectarivorous bat species (Phyllostomidae: Glossophaginae) at flowers of two key-resource plants.

Animals should maximize their energy uptake while reducing the costs for foraging. For flower-visitors these costs and benefits are rather straight forward as the energy uptake equals the caloric content of the consumed nectar while the costs equal the handling time at the flower. Due to their energetically demanding lifestyle, flower-visiting bats face particularly harsh energetic conditions and thus need to optimize their foraging behavior at the flowers of the different plant species they encounter within their habitat. In flight cage experiments we examined the nectar-drinking behavior (i.e. hovering duration, nectar uptake, and the resulting feeding efficiency) of the specialized nectar-feeding bat Hylonycteris underwoodi and the more generalistic Glossophaga commissarisi at flowers of two plant species that constitute important nectar resources in the Caribbean lowland rainforests of Costa Rica and compared nectar-drinking behavior between both bat species and at both plant species. We hypothesized that the 1) specialized bat should outperform the more generalistic species and that 2) bats should generally perform better at flowers of the nectar-rich flowers of the bromeliad Werauhia gladioliflora than at the relatively nectar-poor flowers of the Solanaceae Merinthopodium neuranthum that has an extremely long flowering phase and therefore is an extremely reliable nectar resource, particularly for the specialized Hylonycteris. While we did not find substantial differences in the feeding efficiency of the generalist G. commissarisi, we observed an increased feeding efficiency of the specialized H. underwoodi at flowers of the nectar-poor M. neuranthum. This suggests that familiarity and ecological importance are more important determinants of the interaction than just morphological traits. Our results demonstrate that in addition to morphology, behavioral adaptations are also important drivers that determine the fitness of nectar-feeding bats. Both familiarity with and the ecological importance of a resource seem to contribute to shaping the interactions between pollinating bats and their plants.

The invasive bumblebee Bombus terrestris (Linnaeus, 1758) disrupts the adaptive function of heteranthery by indiscriminately visiting the pollinating and feeding anthers of Senna arnottiana flowers.

Heteranthery, the presence of different types of anthers on the same flower, is a floral adaptation that aims to balance the need for pollinators to collect pollen as a food resource while ensuring sufficient pollen for pollination. We investigate the role of heteranthery in the pollination of Senna arnottiana flowers and how it is affected by the behaviour of visiting bee species, with a particular focus on the impact of the invasive bumblebee Bombus terrestris. In three populations of S. arnottiana we measured the size of three sets of anthers and style, stigma-anther separation, pollen quantity and fruit set, and contrasted it with the body size, behaviour, and pollination effectiveness of all floral visitors. Different bee species visited S. arnottiana flowers, and their foraging behaviour varied. Large-bodied native bees, including Centris cineraria, Caupolicana sp. and Cadeguala occidentalis, preferentially visited short anthers, whereas B. terrestris, an exotic bumblebee, foraged from both short and long anthers without distinction. In addition, B. terrestris contacted the stigma at a lower rate than large-bodied native bees. Instead of concentrating its pollen-gathering efforts on the feeding anthers, as predicted by the "division of labor" hypothesis, B. terrestris indiscriminately visited both types of anthers similarly. This behaviour of B. terrestris may disrupt the adaptive significance of heteranthery by mixing the roles of pollination and feeding anthers of S. arnottiana. Therefore, our results highlight the potential disruption of this relationship by exotic pollinators and the need to consider it in conservation efforts.

Scavenging in two mountain ecosystems: Distinctive contribution of ants in grassland and non-ant invertebrates in forest.

Scavenging is a key process for the cycling of nutrients in ecosystems, yet it is still neglected in the ecological literature. Apart from the importance of specific groups of animals in scavenging, there have been few ecological studies that compare them. Furthermore, the ecological studies on scavenging have mainly focused on vertebrates despite the crucial importance of invertebrates in this process. Here, we performed a large-scale ant suppression and vertebrate exclusion experiment to quantify the relative contribution of ants, non-ant invertebrates and vertebrates in scavenging nitrogen-rich (insect carcasses) and carbon-rich (seeds) baits in two contrasting mountainous habitats in Brazil (grasslands and forests). Overall, bait removal was 23.2% higher in forests than in grasslands. Ants were the primary scavengers in grasslands, responsible for more than 57% of dead insect larvae and seed removal, while, in forests, non-ant invertebrates dominated, removing nearly 65% of all baits. Vertebrates had a minor role in scavenging dead insect larvae and seeds in both habitats, with <4% of removals. Furthermore, our results show that animal-based baits were more consumed in forests than seeds, and both resources were equally consumed in grasslands. Therefore, we demonstrate the superiority of invertebrates in this process, with a particular emphasis on the irreplaceable role of ants, especially in this grassland ecosystem. As such, we further advance our knowledge of a key ecosystem process, showing the relative importance of three major groups in scavenging and the differences in ecosystems functioning between two contrasting tropical habitats.