Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

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The insectivorous bats of arid and semi-arid ecosystems have been poorly studied in México. The aim of this work was to determine the richness and activity of insectivorous bats in arid landscapes of central México over an annual cycle and identify the landscape and environmental features related to relative abundance patterns of bats. We carried out captures with mist nets and active acoustic monitoring in 10 transects, semi-active monitoring in eight stations, and passive monitoring in two desert grassland and scrub sites in Aguascalientes and Jalisco, from January to December 2012. The activity index of each insectivorous species was calculated and related to the local features at the landscape level. An automated monitoring weather station was established in the study area to explore the potential effect of environmental conditions on activity through time. Two species of insectivorous bats were captured: Myotis melanorhinus and Myotis occultus; seven additional species belonging to three families were acoustically identified, with Tadarida brasiliensis as the most active species. Activity levels were concentrated during the spring (April-June) and from mid-summer to late fall (August-October). The null activity in winter (January-March) and the increased activity of T. brasiliensis in the spring suggest migratory movements of the species in the region. The highest values of the activity index were recorded in the proximity of water bodies and ravines. Overall activity was recorded at temperatures between 6.8 and 20.3 °C, and under wind speeds between 1.6 and 24.1 km/h.

Since the term was coined in 2003, landscape genetics (LG) is a field that integrates population genetics, landscape ecology, and spatial analytical techniques to quantify the effects of landscape on microevolutionary processes.  Despite the growing interest in LG, there is little knowledge about the trends in LG research for America in general and regarding mammals in particular, as well as about which ecosystems are being most studied.  Deserts represent nearly one-third of the Earth’s surface and are characterized by high heterogeneity and species richness.  However, they are underrepresented in the LG literature.  Hence, we performed a thorough review of published scientific articles addressing LG of mammals in America, with emphasis on deserts. The objectives were to 1) determine the mammal groups that have been most studied; 2) establish the representation of desert ecosystems; 3) describe the research questions and analytical methods most frequently used; and 4) summarize the key landscape factors and environmental variables associated with genetic diversity and structure patterns of mammals in America.  We conducted a comprehensive literature search of published articles between 2003 and 2019 in the Web of Science (http://apps.webofknowledge.com) based on search words specific to the revision subject.  We verified and screened the articles recovered, and gathered basic information (species, authors, publication year), together with the research questions addressed and the genetic and statistical methods used.  We recovered 36 publications on LG involving mammals in America; of these, only eight were conducted on desert ecosystems (Table 1).  Rodentia was the most represented order in all American ecosystems (n = 20), while Artiodactyla (n = 4) was specifically represented in deserts.  Of all studies, the most common research questions focused on estimating ‘connectivity’ (n = 14) and ‘genetic structure’ (n = 12), and the most frequent analytical methods were Mantel and partial Mantel tests.  Dispersal capabilities and vegetation cover were the most important variables regarding the genetic structure of desert populations.  Most studies evaluated connectivity with simple and partial Mantel tests, but the use of novel methodologies (i. e., genomics) was also identified.  Ecological traits of species, particularly for rodents, and vegetation cover were the main factors related to genetic patterns in deserts.  Notably, we identified that North America is the most studied region, while LG studies with mammals are scarce in Mexico and South America (one study encompassed North and Central America), as well as in desert ecosystems, hence the urgency to conduct studies in those regions and in deserts. 

A long-standing belief among humans is that the behaviors we call making music and dancing are thought to be strictly human activities.  Rapidly accumulating evidence, however, tells a different story.  Both music and dance are characterized by sensitivity to and moving in response to rhythms.  Among humans, these two behaviors are ubiquitous in all living cultures and can be traced back in our Neanderthal ancestors at least 50,000 years, and probably much longer.  It is well established that in humans these two rhythmic behaviors play important social functions, and in recent years have been increasingly noted as well for their health benefits.  All of this has called attention to similar behaviors in non-humans.  Many examples have been noted among mammals, birds, reptiles, amphibians and even bony fish. Neurologists became interested in understanding the neural mechanisms for these rhythmic behaviors and found that rhythmic behaviors are organized in one of the most ancient parts of the vertebrate brain, namely the subcortical posterior parietal cortex which is located just on top of the uppermost ending of the spinal cord.  This anatomy was then found to be the same in almost all vertebrates going back in history for many millions of years to the bony fish.  So, now it is understandable why music and dance are so widespread among the vertebrates and why there seems to be the potential for these rhythmic behaviors to appear in most of the vertebrates.  This discovery also emphasizes the potential availability of the beneficial effects of these behaviors.  Needless to say, there is also the prospect of an emerging opportunity for much exciting and important research on mammals.  

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Due to the potential of bats to travel long distances, the great diversity of habitats in which they are found, and their biological peculiarities, bats typically have been excluded in biogeographic analyses. However, like other mammals, bats show common distributional patterns strongly influenced by their biotic and abiotic interactions, aspects that have been poorly analyzed mainly due to technical and methodological limitations. Such occurrence data are limited to a subset of a species’ range, the scale of occurrence records, characteristics of the life history (e.g., territory size, vagility) of the taxa being studied, and issues of environmental variable selection and, therefore, the modeling methods and the evaluation of them. In this work, the objectives were to: 1) Evaluate the spatial variation in bat richness in Mexico, both for the order as a whole and at the family taxonomic level. 2) Quantify overlapping species occurrences and corresponding richness values in order to statistically model and generate bat richness maps at different taxonomic levels. 3) Explore the relationship of bat richness with environmental factors and with the biogeographic regions proposed for Mexico. 4) Identify areas of interest with high richness. The information available on the Global Biodiversity Information Facility database for bat species with distribution in Mexico was downloaded, and clearly erroneous records deleted. Using the Kriging Ordinary utility (KO), inside the QGIS software, a geostatistical analysis interpolation data was used to determine patterns of richness. The relationship of bat richness to climate, vegetation, and the biotic provinces proposed for Mexico was also explored. Spatial variation in richness was evaluated at the taxonomic levels of order and family. Based on this determination, areas of interest were identified for their high richness. When considering all species of bats the highest diversity is in the central part of the West, the Northeast zone and on both sides of the Isthmus of Tehuantepec. However, there are differences present at the family level. Deciduous tropical forest vegetation type presents high bat richness, followed by pine-oak forest and evergreen tropical forest. Temperate sub-humid, warm sub-humid and warm-humid climate types correspond to the highest bat richness of both order and family. Collection localities are not uniformly distributed over the country, most of them being concentrated in the west, east and south of the country, while there are very few records in the north and central plateau, and this is reflected in the richness concentration per cell (values from 0 to 52 species per cell). Protection of the four areas with an overall high concentration of bat richness detected in this analysis should be a priority during the development of conservation strategies.

The Baird’s tapir (Tapirella bairdii) is an endangered species throughout its distribution area, however many aspects of its biology and ecology have been poorly studied, due to its evasive behavior and low densities. The goal of this study was to evaluate the activity patterns of T. bairdii, a large ungulate species from the Neotropics, in relation to moon phases in two sites with different degree of human perturbation: the Calakmul Biosphere Reserve (CBR) and the Nuevo Becal (NB) community. We monitored twenty waterbodies in each site for 18 months using camera traps. The photographic capture rate (CR) and the corresponding moon phases for both sites were recorded. The CR of T. bairdii was 0.054 in NB and 0.029 in CBR. T. bairdii was more active at night and dawn-twilight periods. In general, T. bairdii showed major activity during the dark moon phases but the differences with the light phases were not statistically significant. However, we found a trend of tapirs to be more active in dark nights and in the darkest hours in NB than CBR. The apparent preferences for dark nights in NB could be caused by the perturbation caused by human activities at site, which may have influenced the behavior of the tapir that avoid moving out in periods of abundant light in disturbed sites. More research is needed to confirm this finding.

In Colombia, shrews (Cryptotis) are represented by seven species associated with Andean, high Andean, and Paramo ecosystems of the three national Cordilleras. Of these species, five are endemic to the Andean region of the country. Despite representing the group of mammals with the highest rate of endemic species, the knowledge currently available on aspects such as natural history, distribution, and ecology is limited. This work assesses the current state of knowledge of the shrews of Colombia, discusses taxonomic issues, risks and threats related to conservation, and identifies research needs and priorities. We compile the information on shrews of Colombia available in the literature and databases. We include two of the known species of the country and one to be determined within a phylogenetic context. In general, the knowledge of the shrews of Colombia reveals the lack of ecological and genetic studies. There are unsolved taxonomic questions about the presence of certain species in the different mountain ranges of the country. There is an urgent need to generate molecular information to clarify the richness of the genus in Colombia which, according to our observations, has been underestimated. The knowledge about the shrews of Colombia is still scarce, even when some species were first described more than a hundred years ago. The need to conduct systematic studies and comprehensive morphological descriptions to clarify the richness of the shrews of Colombia is highlighted.

Fleas and sucking lice are important vectors of multiple pathogens causing major epidemics worldwide.  However these insects are vectors of a wide range of largely understudied and unattended pathogens, especially several species of bacteria’s of the genera Bartonella and Rickettsia.  For this reason the aim of the present work was to identify the presence and diversity of Bartonella and Rickettsia species in endemic murine typhus foci in Hidalgo, México.  A cross-sectional study was carried out to collect small mammals and their associated ectoparasites during October, 2014.  Samples of liver and ear of hosts, and ectoparasites were fixed in absolute ethanol and examined to identify the presence of Bartonella and Rickettsia DNA by the amplification of specific fragments of the gltA and ompB genes using conventional PCR.  The recovered sequences were compared with those deposited in GenBank, and phylogenetic analyzes were carried out to identify the position of the pathogens detected with respect to the valid species previously reported worldwide.  A total of 47 fleas and 172 sucking lice, belonging to five families (Ceratophyllidae, Leptopsyllidae, Ctenophtalmidae, Hoplopleuridae, Polyplacidae) and related to six species were collected from 40 rodents of four species and one shrew.  Only four hosts (two P. beatae, and two R. norvergicus) were positive to Bartonella elizabethae, Bartonella vinsonii and Rickettsia typhi.  In the case of ectoparasites, 23 specimens of two flea species (Peromyscopsylla hesperomys and Plusaetis mathesoni) tested positive for B. vinsonii.  No evidence of Bartonella or Rickettsia was detected in any lice.  Our findings represent the first record of Bartonella elizabethae a confirmed zoonotic pathogen causing endocarditis in México and several new associations of Bartonella with Mexican flea species, which highlight the importance of the establishment of active entomological surveillance in wildlife.