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The lie is considered a moral flaw, always has a negative connotation. Nevertheless its use is very extended from the biological point of view as mechanism of survival and in the human being, even from the point of view of social integration. Self-deception, considered a supreme manifestation of the human use of lies, is closely related to the generation of optimism and hope, people with problems to integrate self-deception have more frequently pathological alterations in mood, especially depression. The advantages and disadvantages of the use of lying to promote self-deception in patients with terminal illness are analyzed from some ethical-philosophical points of view. [ABSTRACT FROM AUTHOR]

Sexual segregation in the white-tailed deer is very common in temperate habitats. Two main hypotheses have been used to explain this pattern: one based on the differential risk of predation between the sexes and the other, sexual dimorphism. We evaluated whether sexual segregation is occurring in a tropical population of white-tailed deer by examining diet quality as measured by the concentration of faecal nitrogen (FN), expressed as a percentage of crude protein in the diet. A fuzzy clustering method of classification was used to separate the faecal groups of adult males and females over two different reproductive seasons. Using permanent transects during the reproductive and non-reproductive seasons, we collected 113 faecal groups in a large area of tropical dry forest. Sixty-three faecal groups belonged to females, and 50 belonged to males according to the fuzzy classification. There were significant differences in the percentage of faecal crude protein between sexes [analysis of variance (ANOVA)F = 7.011; df = 1;P = 0.009], with higher concentrations in the pellets identified as those of females. However, there was no difference in the concentration of FN between the reproductive and non-reproductive seasons (ANOVAF = 1.997; df = 1;P = 0.1604). The results show that in wild populations of white-tailed deer in the tropics there is sexual segregation: the observed differences in FN concentration best fit the prediction of the sexual dimorphism hypothesis, given that the females appear to consistently feed on better quality forage. As such, the explanation of sexual segregation of deer in a tropical dry forest must take into account that the forces behind segregation are not only reproductive strategies, but also the morphological and physiological differences imposed by sexual dimorphism in this species. [ABSTRACT FROM AUTHOR]

El manatí antillano (Trichechus manatus manatus) es considerado una especie en peligro de extinción en México. En la zona norte del golfo de México se han documentado extinciones locales, y se sabe que la población remanente con distribución más norteña se encuentra en el Sistema Lagunar de Alvarado (SLA). El objetivo de este estudio fue determinar la distribución del manatí en el SLA. El sistema presenta una extensión de 267,010 ha que incluyen cientos de lagunas, áreas inundables y docenas de ríos. La localización de los manatíes se realizó mediante muestreos en transectos lineales sistemáticos en una lancha de 7.6 m de eslora. El esfuerzo de muestreo fue de 332.36 h, con un promedio de 7.38 h d-1 en 45 recorridos. En total se obtuvieron 13 avistamientos de manatíes: siete observados de manera directa, cinco detectados mediante el uso del hidrófono y uno mediante el uso de una ecosonda. En cada registro se tomaron las coordenadas geográficas y se integraron a un sistema de información geográfica para analizar su distribución. La distribución del manatí no se dio de manera uniforme en el área de estudio. Los manatíes se observaron en áreas muy específicas dentro del SLA, consideradas como parte de su hábitat, principalmente en zonas que cuentan con cuerpos de agua interiores, algunas otras áreas estuarinas y palustres, y algunos humedales generalmente con una vegetación en condiciones apropiadas. El SLA es de suma importancia para la conservación de los manatíes, ya que es el último sitio con poblaciones viables en Veracruz y en el norte del golfo de México. [ABSTRACT FROM AUTHOR]

Urbanization is rapidly increasing worldwide, leading to rising levels of pollution, one of the major drivers of environmental change; yet little is known about the relationship between urbanization intensity and pollution levels in pollinator taxa. Toxic metals are among the most common contaminants in urban environments, but few data exist on their presence in the flora and fauna of cities in Latin America, one of the world's most urbanized and biologically diverse regions. In this study, we used an urban-rural gradient approach to analyze the relationship between the concentrations of eleven metals present in adult honeybees (Apis mellifera) and the degree of urbanization within twelve landscapes in the metropolitan area of Pachuca, Hidalgo, which forms part of the megalopolis of Mexico City. Metal concentrations were compared with previously reported values contrasting honeybees from urban and rural areas after standardizing urbanization levels among published reports. The concentrations of Ag, Cr, Cu, and Zn in honeybees increased significantly with the degree of urbanization. Urbanization was not found to influence the levels of Al, Ba, Cd, Mn, and Sr in honeybees. The maximum concentrations of six metals in our urban sites (Al, Ba, Cd, Cu, Mn, and Sr) were higher than the maximum values reported for bees in other urban areas. The concentrations of two metals measured in our study (Cr and Zn) were within the range of values previously published for urban areas. Compared to other studies, we did not detect Pb in the body of honeybees. We conclude that the concentrations of Ag, Cr, Cu, and Zn present in honeybees are a quantitative reflection of the degree of urbanization in central Mexico. Our results highlight the need to monitor metal emission sources in this and other areas and investigate their effects on bees and other pollinator taxa., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Urban areas represent a spectrum that goes from being safe habitats for biodiversity (i.e., habitats more or equally preferred, without costs to fitness) to being ecological traps (i.e., habitats more or equally preferred, but with costs to fitness). Given the imminent urban expansion, it is valuable to assess how biodiversity is responding to urbanization and thus generate timely conservation strategies. We systematically review the urban ecology literature to analyze how much do we know about the role of urban areas as ecological traps. Using a formal meta-analytical approach, we test whether urban areas are functioning as ecological traps or as safe habitats for different taxonomic groups. We generated a data set of 646 effect sizes of different measures of habitat preferences and fitness from 38 papers published between 1985 and 2020. The data set covered 15 countries and 47 urban areas from four continents, including 29 animal species. Studies from North America and Europe were best represented, and birds were the most studied taxa. Overall, the meta-analysis suggests that urbanized habitats are functioning more as safe sites than as ecological traps, mainly for certain species with characteristics that have allowed them to adapt well to urban areas. That is, many of the studied species prefer more urbanized habitats over other less urbanized sites, and their fitness is not modified, or it is even increased. However, there was high heterogeneity among studies. We also performed meta-regressions to identify variables accounting for this heterogeneity across studies and we demonstrate that outcomes may depend on methodological aspects of studies, such as study design or the approach used to measure habitat preference and fitness. More research is needed for poorly studied regions and on a wider range of species before generalizations can be made on the role of urban areas for biodiversity conservation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Climate change scenarios show that water availability could be decreasing in the near future, adding to the increasing problem of the growing water demands in socioeconomic sectors. The aim of this work was to generate a geographically explicit water balance concerning availability vs. demand in an overpopulated region of Mexico. Water balance and water deficit models were made for three periods of time: 1970-2000, and two future periods of time (2041-2060 and 2061-2080). Three global climate models were used in addition to two different climate scenarios from each (Representative Concentration Pathways (RCP) RCP 4.6 and RCP 8.5). Water demand for socioeconomic sectors was calculated through the water footprint. Water availability was 197,644.58 hm 3 /year, while that the water demand was 59,187 hm 3 /year. The socioeconomic sectors with the highest demand were domestic services (48%), agriculture (27%), livestock agriculture (20%), and timber production (5%). The highest water availability areas were not the same as those with the highest demand and vice versa. However, 39% of municipalities had a higher water demand than its availability. A significant reduction in water availability was identified, considering an interval of -15% to 40%. This variation depends on climate models, scenarios, and period of time. Areas with overpopulated cities in the region would have higher pressure on water availability. These results could be used in the implementation of public policies by focusing on adaptation strategies to reduce water deficit in the immediate future.

Urbanization is one of the most significant land cover transformations, and while climate alteration is one of its most cited ecological consequences we have very limited knowledge on its effect on species' thermal responses. We investigated whether changes in environmental thermal variability caused by urbanization influence thermal tolerance in honey bees ( Apis mellifera ) in a semi-arid city in central Mexico. Ambient environmental temperature and honey bee thermal tolerance were compared in urban and rural sites. Ambient temperature variability decreased with urbanization due to significantly higher nighttime temperatures in urban compared to rural sites and not from differences in maximum daily temperatures. Honey bee thermal tolerance breadth [critical thermal maxima (CT max )-critical thermal minima (CT min )] was narrower for urban bees as a result of differences in cold tolerance, with urban individuals having significantly higher CT min than rural individuals, and CT max not differing among urban and rural individuals. Honey bee body size was not correlated to thermal tolerance, and body size did not differ between urban and rural individuals. We found that honey bees' cold tolerance is modified through acclimation. Our results show that differences in thermal variability along small spatial scales such as urban-rural gradients can influence species' thermal tolerance breadths., Competing Interests: The authors declare there are no competing interests.

Quantifying differences in species composition among communities provides important information related to the distribution, conservation and management of biodiversity, especially when two components are recognized: dissimilarity due to turnover, and dissimilarity due to richness differences. The ecoregions in central Mexico, within the Mexican Transition Zone, have outstanding environmental heterogeneity and harbor huge biological richness, besides differences in the origin of the biota. Therefore, biodiversity studies in this area require the use of complementary measures to achieve appropriate information that may help in the design of conservation strategies. In this work we analyze the dissimilarity of terrestrial vertebrates, and the components of turnover and richness differences, among six ecoregions in the state of Hidalgo, central Mexico. We follow two approaches: one based on species level dissimilarity, and the second on taxonomic dissimilarity. We used databases from the project "Biodiversity in the state of Hidalgo". Our results indicate that species dissimilarity is higher than taxonomic dissimilarity, and that turnover contributes more than richness differences, both for species and taxonomic total dissimilarity. Moreover, total dissimilarity, turnover dissimilarity and the dissimilarity due to richness differences were positively related in the four vertebrate groups. Reptiles had the highest values of dissimilarity, followed by mammals, amphibians and birds. For reptiles, birds, and mammals, species turnover was the most important component, while richness differences had a higher contribution for amphibians. The highest values of dissimilarity occurred between environmentally contrasting ecoregions (i.e., tropical and temperate forests), which suggests that environmental heterogeneity and differences in the origin of biotas are key factors driving beta diversity of terrestrial vertebrates among ecoregions in this complex area.

Baird's tapir (Tapirus bairdii) is endangered primarily because of habitat loss and fragmentation, and overhunting throughout its distribution range. One of the priority land areas for the conservation of this species is the Northern part of its range in the Chimalapas forest, Oaxaca. The aim of this research was to determine the relative abundance, population struc- ture, habitat preferences and activity patterns of Baird's tapir (Tapirus bairdii) in the Chimalapas forest, Oaxaca, Mexico, through the non-invasive technique of camera-trap sampling. A total of five sampling sessions were undertaken among 2009-2013, and used a total of 30 camera-traps in each period. The determinant factor of the sampling design was the hunting between two study areas. A total sampling effort of 9000 trap-days allowed to estimate an index of relative abundance (IRA) of 6.77 tapir photographs/1,000 trap-days (n = 61). IRA varied significantly between sampling stations (Mann-Whitney, p < 0.01). The frequency of Baird's tapir photos was higher in the dry season in tropical rain forest without hunting (χ2, p < 0.5). In the rainy season, the tropical rain forest and secondary vegetation habitats showed higher photo frequency than expected from random (χ2, p < 0.5). Considering population structure, a 95.08% of adult animals was obtained in photographic records (n = 58). Three types of activity pattern were observed, with more nocturnal records (88.33%; Kruskal-Wallis, p < 0.05). The Chimalapas forest appears to be the second most important terrestrial priority ecoregion, just after the Mayan Forest (Campeche, Chiapas, Quintana Roo), for the conservation of tapir populations, not only for Mexico but also for Central America.

Background: It has been found that the cholesterol and triglyceride values are higher in preeclampsia than in normal pregnancy, even though it is unclear whether these levels are related to the severity. The aim of this study was to determine the correlation between dyslipidemia and severity in preeclampsia., Methods: Comparative cross-sectional study in 200 patients, 100 with normal pregnancy and 100 with preeclampsia. The age, gynecological and obstetric history, total cholesterol and triglycerides were identified. Descriptive statistics were used: Student's t test for comparing the group of patients with preeclampsia and normal pregnancies, and ANOVA and odds ratio for the subanalysis of mild and severe preeclampsia., Results: No statistically significant differences in age or cholesterol were found. Triglycerides showed a statistically significant difference: they were higher in relation to the severity of preeclampsia (normal pregnancy: 245 mg; mild preeclampsia: 308 mg; severe preeclampsia: 349 mg)., Conclusions: Elevated levels of cholesterol and triglycerides in patients with preeclampsia showed no consistent relationship with the severity of preeclampsia.

We explore the influence of spatial grain size, dispersal ability, and geographic distance on the patterns of species dissimilarity of terrestrial vertebrates, separating the dissimilarity explained by species replacement (turnover) from that resulting from richness differences. With data for 905 species of terrestrial vertebrates distributed in the Isthmus of Tehuantepec, classified into five groups according to their taxonomy and dispersal ability, we calculated total dissimilarity and its additive partitioning as two components: dissimilarity derived from turnover and dissimilarity derived from richness differences. These indices were compared using fine (10 x 10 km), intermediate (20 x 20 km) and coarse (40 x 40 km) grain grids, and were tested for any correlations with geographic distance. The results showed that total dissimilarity is high for the terrestrial vertebrates in this region. Total dissimilarity, and dissimilarity due to turnover are correlated with geographic distance, and the patterns are clearer when the grain is fine, which is consistent with the distance-decay pattern of similarity. For all terrestrial vertebrates tested on the Isthmus of Tehuantepec both the dissimilarity derived from turnover and the dissimilarity resulting from richness differences make important contributions to total dissimilarity, and dispersal ability does not seem to influence the dissimilarity patterns. These findings support the idea that conservation efforts in this region require a system of interconnected protected areas that embrace the environmental, climatic and biogeographic heterogeneity of the area.

Endothelial dysfunction is a fundamental characteristic in the physiopathology of preeclampsia. Currently, a series of markers which explain endothelial dysfunction have been identified. The recognition of endothelial dysfunction has been used to realize an early diagnosis of preeclampsia, as soon as the classification of a possible prognosis. Nevertheless the detection of these markers is not accessible to the majority of hospitable centers that treat patients with preeclampsia. One indirect marker of endothelial dysfunction with a greater accessibility is the assessment of peripheral blood smear. Several studies had proved the presence of endothelial dysfunction by identification of red blood cells crenated in peripheral blood smear led us also to measure the impact in the evolution of the disease.