Physical Activity and Cardiorespiratory Fitness in Tarahumara and Mestizo Adolescents from Sierra Tarahumara, Mexico.

OBJECTIVES: Our purpose was to explore the levels of cardiorespiratory fitness (CRF) and the relationship between CRF, physical activity, and other physical traits in traditional and nontraditional Tarahumara, and Mestizo adolescents from Sierra Tarahumara, Mexico. METHODS: A sample of 87 adolescents aged 16.9 ± 1.2 years (mean ± SD) performed the Margaria step test to quantify CRF. Physical activity was estimated using the International Physical Activity Questionnaire. Blood pressure (BP) and anthropometric measures were taken to estimate body composition and other physical characteristics. RESULTS: Traditional Tarahumara showed higher levels of CRF than nontraditional Tarahumara and Mestizo adolescents (F = 5.5, p = .006). The time allotted to sedentary activities was higher in the Mestizo and nontraditional Tarahumara (χ2 = 10.17, p = .006). In nontraditional Tarahumara, adiposity was associated with CRF reduction (r2 = -.63, p = .00), while vigorous physical activities were positively associated with CRF (r2 = .43, p = .03) and negatively associated with the z-score of body fat (r2 = -.42 p = .03). Finally, CRF was negatively associated with fat percentage (r2 = -.27, p = .00) and systolic blood pressure (r2 = -.09, p = .04) in the Mestizo. In this group, walking activities (r2 = -.25, p = .003) and total physical activity score (r2 = -.11, p = .03) had a positive association with the CRF, while moderate activities had a negative association with the body mass index (r2 = .09, p = .04), and vigorous activities were negatively associated with body weight (r2 = .11, p = .03). CONCLUSIONS: In the sampled nontraditional Tarahumara and Mestizo adolescents, moderate and vigorous physical activities were important factors in determining levels in CRF, fat percentage, and other health parameters.

Cryptic speciation in the Caesalpinia hintonii complex (Leguminosae: Caesalpinioideae) in a seasonally dry Mexican forest.

BACKGROUND AND AIMS: [corrected] The Caesalpinia hintonii group comprises six species of endemic shrubs or trees, C. epifanioi, C. hintonii, C. laxa, C. macvaughii, C. melanadenia and C. oyamae, found in scattered patches of seasonally dry forest in the Río Balsas depression and the neighbouring Tehuacán-Cuicatlán valley, which are part of the Mexican morphotectonic province of Sierra Madre del Sur. An evaluation is made of phylogeographic patterns and genetic diversity with a phylogenetic analysis of the C. hintonii complex in order to study the dynamics of speciation in this endemic group of legumes. METHODS: A phylogeographic study based on four highly variable non-coding plastid regions (trnL intron, trnL-F intergenic spacer, trnH-psbA intergenic spacer, and accD-psaI intergenic spacer) was carried out for the Caesalpinia hintonii complex. Five of the six taxa of the C. hintonii complex were included. KEY RESULTS AND CONCLUSIONS: The plastid analyses involving multiple accessions of each taxon from throughout their ranges resolved C. epifanioi and C. hintonii as well-supported clusters, but C. oyamae has two unexpectedly divergent lineages. Two well-supported geographic clades: eastern (C. epifanioi, C. melanadenia and C. oyamae) and western (C. hintonii and C. macvaughii) were established. The analyses performed provide evidence of recent morphostatic radiation in C. oyamae resulting from isolation and local adaptation. This pattern of genetic differentiation without morphological divergence may be a model that fits many groups of tropical woody taxa inhabiting similarly dry forests subjected to shifting selection.

A new species of Erythrostemon (Leguminosae, Caesalpinioideae) from the western Río Balsas Depression, Mexico.

A new legume species from a seasonally dry forest of the Western Río Balsas Depression, in the states of Guerrero and Michoacán, Mexico, Erythrostemon guevarafeferii, is herein described and illustrated. The new species shows morphological affinities with Erythrostemon hintonii, from which it is distinguished in having fewer leaflets per pinna, mature leaflets disposed toward the upper half of the pinnae rachises, long inflorescences on curved slender peduncles, abundant red glands on its flowers and inflorescences, and its fruit glabrous with red stipitate glands at maturity. A taxonomic key to the Río Balsas Depression species of Erythrostemon is included.

ResumenUna nueva especie de leguminosa de la Depresión Occidental del Río Balsas en los estados de Guerrero y Michoacán, Erythrostemon guevarafeferii, se describe e ilustra. La nueva especie muestra afinidades morfológicas con Erythrostemon hintonii, de la que se distingue por tener menos pinnas, folíolos maduros glabros dispuestos hacia la mitad superior de las pinnas, las inflorescencias largas sobre pedúnculos delgados que se curvan y flores con abundantes glándulas; legumbre glabra o con glándulas estipitadas rojas cuando esta madura. Se incluye una clave taxonómica de las especies de Erythrostemon que habitan en la Depresión del Río Balsas.