Mexican Plateau Research Articles

Historical biogeography and the evolution of habitat preference in the North American camel spider family, Eremobatidae (Arachnida:Solifugae)

Abiotic variables can influence species distributions, often restricting taxa to an acquired climatic signature or conversely, related species are conserved in the same ecological space over millions of years. An investigation into how abiotic change has shaped geographic distributions of taxa may be key to understanding diversification of lineages, and in the absence of reliable morphological characteristics, such information may support taxonomic units at multiple scales.Here, we examine the historical biogeography and patterns of habitat preference within the North American solifuge family, Eremobatidae. A previous study demonstrated that a major taxonomic revision of Eremobatidae is warranted, however recent studies demonstrate high levels of morphological convergence within the group, thus a re-classification of generic boundaries using additional information must be prioritized before we can formally begin solid revisionary efforts. In this study, we aimed to reconstruct a well-resolved phylogenetic hypothesis of Eremobatidae by filtering UCE loci based on informativeness, by mitigating the effect of cogenic UCE on phylogenetic estimation, and by supplementing our curated UCE loci with mitochondrial information. Using our preferred topology, in conjunction with published estimated divergence dates for Eremobatidae, we inferred a time-calibrated phylogenetic hypothesis to inform the historical biogeography and patterns of habitat preference. The two major habitat types that were observed for Eremobatidae were warm deserts for early diverging taxa and a subsequent evolution to cold deserts and Mediterranean California ecoregions for later diverging taxa. Eremobatid niche space, determined by temperature and precipitation, has been conserved for at least 25 million years in North America, supporting a warm desert origin, and thus supporting high species richness in the Sonoran and Mexican Plateau. Overall, our study provides support for new generic level designations within Eremobatidae.

Increased Dissemination of Aflatoxin- and Zearalenone-Producing Aspergillus spp. and Fusarium spp. during Wet Season via Houseflies on Dairy Farms in Aguascalientes, Mexico.

Crops contamination with aflatoxins (AFs) and zearalenone (ZEA) threaten human and animal health; these mycotoxins are produced by several species of Aspergillus and Fusarium. The objective was to evaluate under field conditions the influence of the wet season on the dissemination of AF- and ZEA-producing fungi via houseflies collected from dairy farms. Ten dairy farms distributed in the semi-arid Central Mexican Plateau were selected. Flies were collected in wet and dry seasons at seven points on each farm using entomological traps. Fungi were isolated from fly carcasses via direct seeding with serial dilutions and wet chamber methods. The production of AFs and ZEA from pure isolates was quantified using indirect competitive ELISA. A total of 693 Aspergillus spp. and 1274 Fusarium spp. isolates were obtained, of which 58.6% produced AFs and 50.0% produced ZEA (491 ± 122; 2521 ± 1295 µg/kg). Houseflies and both fungal genera were invariably present, but compared to the dry season, there was a higher abundance of flies as well as AF- and ZEA-producing fungi in the wet season (p < 0.001; 45.3/231 flies/trap; 8.6/29.6% contaminated flies). These results suggest that rainy-weather conditions on dairy farms increase the spread of AF- and ZEA-producing Aspergillus spp. and Fusarium spp. through houseflies and the incorporation of their mycotoxins into the food chain.

Geochemistry and mineralogy of beach sediments in the northern Gulf of Mexico, Tamaulipas state, Mexico: implication for provenance

Geochemical and mineralogical studies were performed in the La Pesca (LP) and Tesoro Altamira (TA) beach sediments, located in the Tamaulipas state, northern Gulf of Mexico. The main aim of this study is to infer the weathering history and provenance and to discriminate the tectonic environment of the beach sediments. The sediments are composed of quartz with small amounts of accessory minerals such as plagioclase, calcite, orthoclase, microcline, and zircon. Both beach sediments are classified as fine-grained and very well sorted, however LP has coarse skewed and leptokurtic sediments, whereas TA has fine-skewed and very leptokurtic sediments. The chemical index of weathering (CIW’) indicates intense weathering in the source area. The quartz grain microtextures in the LP and TA are classified into mechanical, chemical, and mechanical/chemical origin. Mechanical features such as fractures, pits, percussion marks, abrasion fatigue, and V-shaped marks favor high-energy littoral, fluvial, subaqueous-marine, and aeolian environments. The chemical features indicate solution pits and crystalline overgrowth, which suggests a silica saturated marine environment. The mechanical/chemical features display adhering particles and elongated depressions suggest formation in a sub-aqueous nearshore marine environment. Major and trace elements-based provenance discrimination diagrams indicate a felsic source derived from the Mesa Central (MC), Sierra Madre Oriental (SMOr) and Oaxaquia terranes. The major and trace element concentrations imply a passive margin setting for the northern Gulf of Mexico, which is consistent with the general geology.

USO DEL ENSILADO DE SORGO VARIEDAD TOP GREEN Y VARIEDAD CAÑA DULCE PARA LA PRODUCCIÓN DE LECHE EN SISTEMAS DE PEQUEÑA ESCALA

&lt;p&gt;&lt;strong&gt;Background&lt;/strong&gt;. Sorghum is a crop that stands out as an alternative to maize due to its higher drought tolerance and lower soil fertility demand. &lt;strong&gt;Objective&lt;/strong&gt;. To evaluate the productive response of lactating cows fed maize silage (&lt;em&gt;Zea mays&lt;/em&gt;) in substitution with sorghum silage (&lt;em&gt;Sorghum bicolor&lt;/em&gt; L.). &lt;strong&gt;Methodology&lt;/strong&gt;. The research was carried out in the central highlands of Mexico, in the farmer of a small-scale dairy family. Nine cows were used, distributed in three 3X3 Latin squares with test periods of 14 days, of which 12 were for adaptation of the animals to diets and 2 d to the collection of samples. The treatments were: 1) Top Green = 5 kg DM sorghum silage cv Top Green + 5 kg DM maize silage; 2) Caña Dulce = 5 kg DM sorghum silage cv Caña Dulce + 5 kg DM maize silage; 3) Maize silage = 10 kg DM maize silage (testigo). The study included the productive behaviour of the cows, feed composition and feeding costs. Treatment data were analysed with a split-plot arrangement. &lt;strong&gt;Results&lt;/strong&gt;. Inclusion of sorghum silage in the diet reduced dry matter intake (P&amp;lt;0.05), but did not affect average production (22.9 kg/day) and milk composition of cows (P&amp;gt;0.05). There were no differences (P&amp;gt;0.05) for variables related to the nutritional value of the silages. Although there were no significant differences in animal response variables, economic analysis showed that the inclusion of sorghum silage increased feed costs by 15% due to lower dry matter yields. &lt;strong&gt;Implications&lt;/strong&gt;. Sorghum has been proposed as a resilient alternative to maize especially in drought stress scenarios, when the availability of quality forages decreases and grain and forage prices increase. &lt;strong&gt;Conclusions&lt;/strong&gt;. Although feeding costs were higher, sorghum silage can be a substitute for maize silage.&lt;/p&gt;

Description of the viral community in fecal content of common carp (Cyprinus carpio) living in a naturally preserved wetland on Mexican plateau

IntroductionThe common carp (Cyprinus carpio) is a species that has been used worldwide as a source of protein for humans because of its adaptive capacity to the environment; however, it is also an invasive species. In Mexico, it was introduced to provide an easily accessible source of protein to people in rural areas until its extensive nationwide distribution. The community of viruses in these fish is not completely known. MethodsMassive sequencing, i.e., whole metagenome shotgun (WMS) sequencing, and bioinformatic analysis were used to describe the viral community of common carp (Cyprinus carpio) living in a natural preserved wetland. ResultsThrough sequencer Illumina NextSeq 500/550 we got 484,953,684 sequences from ten samples of fecal content of carp (5 samples to DNA and 5 samples to RNA). The virome comprised 30 viral families (13 DNA families and 17 RNA families), among which viruses related to vertebrates stood out, for example Orthoherpesviridae, Parvoviridae, Astroviridae, Poxviridae, Hantaviridae and Picornaviridae.DiscussionThe most abundant viral taxa corresponded to bacteriophages, most of which are of polyphyletic origin. The results of this work contribute to the knowledge of the different viral taxa found in the common carp in the wild and indicate that these viral taxa may play a role in health and productivity of fish farms.

Roasting affects the final quality of Coffea arabica from the Central Mexican Plateau

Roasting affects the final quality of Coffea arabica from the Central Mexican Plateau

Adaptive shifts in Phanaeini dung beetles of the Mexican plateau cenocron in the Mexican transition zone

Adaptive shifts in Phanaeini dung beetles of the Mexican plateau cenocron in the Mexican transition zone

Helminths of free-ranging dogs and cats in an urban natural reserve in Mexico City and their potential risk as zoonotic agents.

In the Reserva Ecológica del Pedregal of San Ángel, located in the south of Mexico City, Mexico, free-roaming dogs and cats coexist with 148 bird, 33 of mammal, 23 of reptile and seven amphibian species, that represent a remnant of the original fauna of the Mexican Plateau. The negative impact that dogs and cats have on local fauna is unobjectionable, however, the role that these introduced vertebrates play as potential transmitters of infectious diseases for native fauna and humans, is much less understood. Information about parasitic infections in native and introduced animals in this location is scarce. In order to ameliorate this lack of information, the objective of this study is to characterize the helminth fauna of the free-ranging dogs and cats of the ecological reserve. Between 2018 and 2023, 36 Felis silvestris catus and 7 Canis lupus familiaris were studied from the helminthological perspective. Endoparasites were obtained from the digestive tract and were identified to the species level using morphological and molecular evidence. Hosts were parasitized by eight species of helminths: in cats the cestodes Hydatigera taeniaeformis, Mesocestoides sp., Taenia rileyi and the nematode Toxocara cati were recorded, while in dogs, the cestode Taenia pisiformis and the nematodes Ancylostoma caninum, and Uncinaria stenocephala were found. The only species shared between cats and dogs was the cestode Dipylidium caninum. These free-ranging animals act as definitive hosts of 5 species known to have zoonotic potential; their presence in the area may generate a public and animal health problem if programs of dog and cat population control are not continued.

Wolf, little wolf, are you there?... No; I have been extirpated or History of the extirpation of the gray wolf (Canis lupus) in thesouthern part of the Mexican Plateau

After humans, the gray wolf is the mammal that had the largest known natural global distribution. Throughout it, while humanswere hunter-gatherers the gray wolf was a totemic animal, spiritual guide, and friend, but gradually, in Europe and Asia, thisperception changed to that of undesirable vermin that had to be eliminated, due to its predation on domestic animals. Europeansbrought that sentiment to the Americas and the gray wolf was persecuted until it was eradicated from most of its range, includingfrom all of Mexico. In this paper we review the history of its eradication in the southern part of the Mexican Plateau. In this region,the persecution that culminated in its extirpation developed from the 19th Century to the mid-20th Century. The history of the wolfin the region is not unique but it is shared with that of many species when two different cultures meet and capital has the last word

Combining Ability and Reciprocal Effects for the Yield of Elite Blue Corn Lines from the Central Highlands of Mexico.

The development of hybrid plants can increase the production and quality of blue corn, and, thus, satisfy its high demand. For this development, it is essential to understand the heterotic relationships of the germplasm. The objectives of this study were to determine the effects of general (GCA) and specific (SCA) combining ability, as well as the reciprocal effects (REs) on the yields of 10 blue corn lines, and to select the outstanding lines. Diallel crosses were generated with 10 lines and evaluated at the Valle de México Experimental Station in Chapingo, Mexico, and Calpulalpan, Tlaxcala, Mexico. There were differences (p ≤ 0.01) in the hybrids, Loc, effects of GCA, SCA, and REs, and in the following interactions: hybrids × Loc, GCA × Loc, SCA × Loc, and RE × Loc. For GCA, lines Ll, L4, L6, and L9 stood out, with significant values of 3.4, 2.9, 2.9, and 3.1, respectively. For SCA, the hybrids featured were L4 × L10, L2 × L10, L1 × L10, L7 × L8, and L2 × L6, with values of 3.0, 2.5, 2.3, 2.3, and 2.2, and yields of 11.2, 10.2, 10.4, 10.4, and 10.5 t ha-l, respectively. There were no significant REs in these lines. Considerable effects of GCA and SCA were detected; therefore, we concluded that native populations had favorable dominance and additive genetic effects that could be used to support the development of high-yielding lines and hybrids.

Stitching for Material Sensitivity: From Traditional to Activist Embroidery

Cochineal is an insect that has been used for textile dyeing since pre-Hispanic cultures in Mexico. This exposition discusses the use of the cochineal insect as a natural dye for wool and the bridge between ancient indigenous knowledge and contemporary artistic research. A transatlantic connection is created between the Mexican plateau and the Arctic region, merging traditional knowledge, contemporary art, crafting and conceptualisation through an artistic embroidery initiative involving researchers, craft artists and human rights activists living in the province of Lapland in Finland. Documentary photos of artistic practice and research diaries enhance discussion on sustainability, tradition, craftivism, decolonisation and indigenous knowledge. This exposition embraces collaborative craftivism through a group initiative called Embroidered Stances, discussions about material interconnectedness in a web-of-life conceptual structure that includes sheep wool, cactus, cochineal and ancestral knowledge. The endorsement of material sensitivity is narrated into embroideries by the first author Cervantes and discussed, acknowledging complexities within issues of cultural and ecological sustainability.

Livestock in the sustainability of changing livelihoods in high mountain communities in a Natural Protected Area in Central Mexico

Objective: Livelihoods of communities within the high mountain Natural Protected Area for Flora and Fauna ‘Nevado de Toluca’ (NPAFFNT) in the central highlands of Mexico have changed due to statuary limitations established in management program respect to agro-silvopastoral activities. In these communities, the small scale farmers who still rely on livestock, mainly sheep production. There is no knowledge on the sustainability, strengths and weaknesses of these systems and the influence of seasons in this area of marked bioclimatic seasonality. Methodology: The IDEA method to assess sustainability was applied in a small village within NPAFFNT in the dry as in the rainy season. Results: Sustainability is limited by the economic scale while their main strengths were in the agroecological scale in both seasons. Indicators show deficiencies in farmer education, lack of technical assistance, poor local infrastructures, lack of access to institutional support programmes, and the revision of norms for the natural protected area. Conclusions and implications: Results are useful for improving the sustainability of these systems that may improve que quality of life of high-mountain communities and provide ecosystemic services relevant for society. Diversification of income sources are of needed given the limitations that the new statute create on livestock and agricultural activities. It is advisable to increase the educational level of the inhabitants and farmers receive specialized technical training in agricultural and sustainable livestock production.

DESEMPEÑO PRODUCTIVO DE VACAS LECHERAS ALIMENTADAS CON PRADERAS DE KIKUYO SOBRESEMBRADAS CON CENTENO EN SISTEMAS DE PRODUCCIÓN DE LECHE EN PEQUEÑA ESCALA EN LOS VALLES ALTOS DE MÉXICO

&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Small-scale dairy systems contribute to mitigate rural poverty as they provide a stable source of incomes to farming families, and also contribute with over 30% of national milk production. However, the dependency on external inputs affects their profitability and sustainability, which added to difficult agroclimatic conditions and limiting management factors as high stocking rate in pastures. It is therefore necessary to evaluate feeding strategies better adapted to conditions in these systems to improve cattle diets based on quality forages reducing external dependency and thus, costs. A means to increase herbage yields in pastures is overseeding with annual fast-growing cereals. &lt;strong&gt;Objective: &lt;/strong&gt;The objective was to evaluate the productive performance of dairy cows on two feeding strategies based on grazing, and the analysis of costs in small-scale dairy systems in the highlands of central Mexico. &lt;strong&gt;Methodology: &lt;/strong&gt;Eight Holstein cows were used on continuous day grazing (8 h/day) under on-farm research with a double cross-over design. Treatments ere: continuous intensive grazing of Kikuyu grass pastures (KY) or Kikuyu grass overseeded with rye (KYCEN) from 6:00 to 16:00 h, plus 4.5 kg DM/day of commercial concentrate. Two groups of four cows balanced for days in milk and daily milk yield were formed, and each group randomly assigned to one of the treatment sequences: KY-KYCEN-KY y KYCEN-KY-KYCEN, with three experimental periods of 14-day each, with 10 days for adaptation to diets and four days for sampling. Pastures were assessed with a split-plot design. Records were for milk yield and composition, live weight and body condition. A partial budget analysis was performed to compare income and feeding costs. &lt;strong&gt;Results: &lt;/strong&gt;There were no statistical differences (P&amp;gt;0.05) in productive performance, with mean 3.5% fat corrected milk yield of 17 kg/cow/day, with 36.6 g/kg, 28.5 g/kg and 43.4 g/kg for milk fat, protein and lactose respectively. There were no significant differences (P&amp;gt;0.05) between treatments for sward height or herbage mass, but there were significant differences (P&amp;lt;0.05) for DM and OM content between treatments, and for CP, NDF, ADF, IVDMD, and EM (P&amp;lt;0.05) between periods. &lt;strong&gt;Implications:&lt;/strong&gt; In the face of complex agroecological scenarios for small-scale dairy systems, it is necessary to assess forages better adapted for these conditions as the inclusion of a fast growing cereal as rye to increase pasture production and increase the forage base in the diets with farm resources as Kikuyo grass, in order to increase the profitability of farms. &lt;strong&gt;Conclusions: &lt;/strong&gt;Since there were no statistical differences in the productive performance of dairy cows, or in economic performance, the conclusion is that treatment KY is the recommended option for this season. Treatment KYCEN requires expenditures in seed and labour, so that it is not a viable option for small-scale dairy systems in this season.&lt;/p&gt;

ENSILADOS MIXTOS DE CEREALES DE GRANO PEQUEÑO EN LA ALIMENTACIÓN DE VACAS EN SISTEMAS DE PRODUCCIÓN DE LECHE EN PEQUEÑA ESCALA

&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;In small-scale dairy systems (SPLPE), multi-species pastures and small grain cereal silages have proven to be an option in the face of potential climate change effects and provide quality forage at low costs in periods of forage shortages. &lt;strong&gt;Objective:&lt;/strong&gt; To evaluate the inclusion of a binary silage of barley and rye, compared to a ternary silage of barley, rye and triticale, in the feeding of dairy cows in small-scale dairy systems, in terms of productive and economic performance. &lt;strong&gt;Methodology&lt;/strong&gt;: In the central Highlands of Mexico and with the participation of a small-scale dairy farmer, the inclusion of these silages in the feed of 6 dairy cows was evaluated under a cross-over design. The treatments included 40% silage (T1, binary; T2, ternary), 36% of conventional feeds (cut pasture, maize straw and alfalfa hay) offered by the participating farmer, and 24% of commercial compound concentrate. The variables evaluated were diet composition, feed intake, yield and milk composition, and an economic analysis made considering feed costs. &lt;strong&gt;Results&lt;/strong&gt;: The neutral detergent fiber content was 4.8% lower in T2 (&lt;em&gt;p&lt;/em&gt;&amp;lt;0.05), a treatment that also presented a 3% higher digestibility and a higher metabolizable energy and crude protein content (&lt;em&gt;p&lt;/em&gt;&amp;lt;0.05). This was due to the incorporation of the ternary silage, a higher quality silage compared to the binary silage. Energy corrected milk production was higher in T2 (&lt;em&gt;p&lt;/em&gt;=0.05), in response to the higher intake and higher digestibility of this treatment. Feeding costs were similar for the inclusion of the two silages and the implementation of the ternary treatment represented an increase of 0.8% in margins over feed costs with compared to the use of the binary silage. &lt;strong&gt;Implications.&lt;/strong&gt; The use of small grain cereal mixtures silages are feasible in small-scale dairy systems to ensure a constant supply of medium quality forage, which together with moderate supplementation can generate high yields and economic income. &lt;strong&gt;Conclusions&lt;/strong&gt;&lt;strong&gt;:&lt;/strong&gt; The inclusion of ternary silage of small grain cereals of barley, rye and triticale, and moderate supplementation with commercial concentrate (24%) and other conventional feeds (36%), is a viable alternative as a feeding strategy in small-scale dairy systems during the dry season maintaining high milk yields and a high profit margin for these systems.&lt;/p&gt;

Geochemistry, petrogenesis, and tectonic setting of the Cúcamo mafic and intermediate volcanic rocks from the Ahualulco Volcanic Complex, San Luis Potosí, Mexico

The Ahualulco Volcanic Complex (AVC) is situated in the north-central part of the San Luis Potosí Volcanic Field (SLPVF) that is found in the southern portion of the Mesa Central (MC). The Cúcamo, AVC is mainly composed of mafic and intermediate volcanic rocks. The present study focuses on understanding the evolution, origin, and magmatic processes and petrogenesis of mafic and intermediate rocks in the Cúcamo, AVC. The Quaternary mafic rocks have porphyritic textures with the mineral assemblage of olivine, and clinopyroxene. These volcanic rocks display high K calc-alkaline basaltic compositions with enrichment in light rare earth elements (LREEs) and incompatible elements. Geochemical modeling reveals that mafic magmas were derived through a partial melting process of a spinel lherzolite source at low degrees of melting (~2 to 15 %) in an extensional regime. The intermediate volcanic rocks show porphyritic and glomeroporphyritic textures with matrix formed by randomly oriented microlites. The main mineral assemblage consists of plagioclase, K-feldspar, and clinopyroxene. These volcanic rocks are characterized by calc-alkaline basaltic andesitic and andesite compositions with enrichment in light rare earth elements and incompatible elements. Geochemical modeling suggests that intermediate rocks were derived from high ratios of assimilation and fractional crystallization processes between mafic melts and continental crust in an extensional environment.

Economic analysis of backyard agriculture and livestock farming in semi-urban areas of the central highlands of Mexico

In the backyard systems in urban and semi-urban areas of the central highlands of Mexico, agriculture and livestock activities are practiced. In order to know the behavior of the economic variables in these farms, a non-probabilistic sampling by quotas was carried out, using the snowball technique, which consisted of applying surveys to a total of 92 producers, which was designed to collect information on the general characteristics of the backyard, social, and economic system, as well as the products generated from agriculture and livestock. With the information collected, an inventory of the plant and animal species that are produced in the backyard system was made, in addition to estimating economic income, variable costs, fixed costs, total costs, profits and the benefit-cost ratio for carrying out livestock activities agriculture or both in backyard systems. It was found that farmers have an average space in the backyard of 360.5 m2 to carry out activities of agriculture, livestock or both. Farmers who carry out agriculture and livestock activities generate higher income and economic profits, compared to those who only carry out one activity, obtaining a benefit of 27.44 cents for each dollar invested, compared to 16.64 and 18.00 cents for developing the activity agriculture and livestock respectively. The agricultural and livestock activity in the backyard systems of the highlands of Mexico, represent an option to generate economic income for families, and generate food products for self-consumption and reduce expenses for food purchases in the family nucleus.

Introduction of Avocado (Persia americana) Fruits in Eastern Himalaya of India: A Review

Avocado (Persia americana) or locally called Phamfal is a subtropical, dicotyledonous, evergreen tree belonging to the family Lauraceae. The avocado tree is originated from a broad geographical area stretching from the eastern and central highlands of Mexico through Guatemala to the Pacific coast of Central America. Avocado is a fruit, produced from tropical trees characterized by a pear shape and blackish green in colour with high nutritional value and creamy texture. Avocado crop can be used in several ways i.e for processed products, exportation and oil extraction, pharmaceutical and cosmetic industries as a raw material thereby generating high value added products.High demand for information on avocado indicates that there is considerable interest in this crop in various parts of India as well as Eastern India. Moreover, avocado can be grown in Darjeeling hilly region and adjoining states of India as the soil and climatic condition is favourable for their growth and development. However, in this region avocado cultivation is very negligible in homestead garden, small and marginal orchard due to lack of scientific knowledge of farmers. So that in this context to identify and conservation of wild and farmers cultivated species of avocado is the major concern for all avocado growers and scientist.

Phylogenomics and Biogeography of the Mammilloid Clade Revealed an Intricate Evolutionary History Arose in the Mexican Plateau.

Mexico harbors ~45% of world's cacti species richness. Their biogeography and phylogenomics were integrated to elucidate the evolutionary history of the genera Coryphantha, Escobaria, Mammillaria, Mammilloydia, Neolloydia, Ortegocactus, and Pelecyphora (Mammilloid Clade). We analyzed 52 orthologous loci from 142 complete genomes of chloroplast (103 taxa) to generate a cladogram and a chronogram; in the latter, the ancestral distribution was reconstructed with the Dispersal-Extinction-Cladogenesis model. The ancestor of these genera arose ~7 Mya on the Mexican Plateau, from which nine evolutionary lineages evolved. This region was the site of 52% of all the biogeographical processes. The lineages 2, 3 and 6 were responsible for the colonization of the arid southern territories. In the last 4 Mya, the Baja California Peninsula has been a region of prolific evolution, particularly for lineages 8 and 9. Dispersal was the most frequent process and vicariance had relevance in the isolation of cacti distributed in the south of Mexico. The 70 taxa sampled as Mammillaria were distributed in six distinct lineages; one of these presumably corresponded to this genus, which likely had its center of origin in the southern part of the Mexican Plateau. We recommend detailed studies to further determine the taxonomic circumscription of the seven genera.

Cold Housing in Central Mexico: Environmental Dissatisfaction and Underheating Lowers Self-Perceived Health in Central Mexico

Despite being perceived as a warm country, winters in the Central Mexican Plateau frequently reach temperatures below zero Celsius. Prolonged exposures to low temperatures resulting in heart and respiratory morbidities are estimated to be responsible for 50% of the reported illness in the plateau, attributable primarily to the design of homes ill-suited to extreme temperatures. Consequently, there is a growing need to ensure that dwellings provide adequate indoor thermal conditions in the region. Hence, on-site sensors were used to collect temperature and relative humidity data every five minutes in 26 living rooms in the Plateau for 11 months. From these data, a subsample was determined, resulting in dwelling-level thermal comfort and health surveys on 15 homes. Computer simulations were used to investigate whether the building itself could provide thermal comfort under different retrofitting scenarios. Multiple linear regression relating the Predicted Percentage Dissatisfaction (PPD) index to self-perceived health was undertaken. Both monitored and simulated results were matched against our underheating model, finding that 92% of the homes had cold indoor environments, some even during summer. High PPD and intense levels of underheating were positive predictors of higher self-reported health problems. More self-reported health problems were correlated with both lower life satisfaction and self-worth, and with subjects’ use of more adaptive strategies against environmental dissatisfaction. Dynamic computer simulations suggested that indoor thermal environments could be improved by enforcing the non-utilised standard NOM-ENER-020, which recommends the addition of insulation on walls and roofs. These findings suggest that the cold environments within homes of the plateau influence the self-perceived physical and mental health of its population. Hence, the application of adequate measures, such as retrofitting homes with stronger standards than the existing NOM-ENER-020 are needed in place.

Vanishing of the mighty tunales of central Mexico: A 5-century history of landscape change

Before the 16th century, tunales, majestic forests of arborescent nopales (Opuntia spp.), were a signature of the southern part of the Mexican Plateau. They were crucial for nonagricultural humans and wildlife and created the cultural identity of the region. Notwithstanding this, they have been drastically reduced and disparaged into modern times. We aimed at reconstructing the history of the disappearance of these tunales and elaborate on the ecological and cultural impacts of such disappearance. The historicizing of such processes is critical to establish restoration objectives concordant with ecological timeframes, rather than by human memory. To fulfill our objective, we reviewed published formal and gray literature (i.e., publications with limited circulation, theses), and unpublished archival documents, complementing this information and interpreting it with our own &amp;gt;25-year research experience each in the region. Despite some differing opinions, most 15th-century tunales were natural. Agricultural development in the 17th–19th centuries affected mostly tunales in humid bottomlands. Those on hills and slopes apparently escaped this initial transformation. After the Mexican Revolution (1910–1921), the plowing of hills and slopes destroyed many remaining tunales. Some persisted into the 21th century, but their felling has continued. Our study exemplifies how natural iconic communities once widely distributed can vanish almost inadvertently. With the loss of the tunales, the region has lost a unique, iconic plant community which harbored several plant species endemic to Mexico. Arborescent nopales are hardy, but to avoid the complete disappearance of the tunales, their ecological and biocultural importance and significance must be revaluated, and strong lobbying efforts and management actions developed.