The southern Yucatán contains the largest expanse of seasonal tropical forests remaining in Mexico, forming an ecocline between the drier north of the peninsula and the humid Petén, Guatemala. The Calakmul Biosphere Reserve resides in the center of this region as part of the Mesoamerican Biological Corridor. The reserve's functions are examined in regard to land changes throughout the region, generated over the last 40 years by increasing settlement and the expansion and intensification of agriculture. These changes are documented from 1987/1988 to 2000, and their implications regarding the capacity of the reserve to protect the ecocline, forest habitats, and butterfly diversity are addressed. The results indicate that the current landscape matrix serves the biotic diversity of the reserve, with several looming caveats involving the loss of humid forests and the interruption of biota flow across the ecocline, and the amount and proximity of older forest patches beyond the reserve. The highly dynamic land cover changes underway in this economic frontier warrant an adaptive management approach that monitors the major changes underway in mature forest types, while the paucity of systematic ecological and environment-development studies is rectified in order to inform policy and practice.

Needs assessment models have been generally focused on the identification and prioritization of needs, analysing formal resources available in the community as possible solutions for existing problems. These kinds of models have assumed that formal services are the primary source of support for individuals in need. However, a great deal of the investigations in the field of Social Psychology have shown that the main source of help and support when facing a problem is not formal organizations, but people's own informal networks. In this article, we therefore propose a needs assessment model that emphasizes the importance of analysing both formal and informal social resources. The application of this model to assess Moroccan immigrants' needs in the south of Spain shows the anticipated low level of utilization of formal services and programmes, one that contrasts with the high use of informal networks as an essential source of social support for this group of immigrants. These results reveal the limitations of traditional needs assessment models, and the importance of incorporating the analysis of informal social support as a key resource for need satisfaction, particularly in the case of immigrant populations.

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BackgroundRecent studies have demonstrated the utility of DNA barcoding in the discovery of overlooked species and in the connection of immature and adult stages. In this study, we use DNA barcoding to examine diversity patterns in 121 species of Nymphalidae from the Yucatan Peninsula in Mexico. Our results suggest the presence of cryptic species in 8 of these 121 taxa. As well, the reference database derived from the analysis of adult specimens allowed the identification of nymphalid caterpillars providing new details on host plant use.Methodology/Principal FindingsWe gathered DNA barcode sequences from 857 adult Nymphalidae representing 121 different species. This total includes four species (Adelpha iphiclus, Adelpha malea, Hamadryas iphtime and Taygetis laches) that were initially overlooked because of their close morphological similarity to other species. The barcode results showed that each of the 121 species possessed a diagnostic array of barcode sequences. In addition, there was evidence of cryptic taxa; seven species included two barcode clusters showing more than 2% sequence divergence while one species included three clusters. All 71 nymphalid caterpillars were identified to a species level by their sequence congruence to adult sequences. These caterpillars represented 16 species, and included Hamadryas julitta, an endemic species from the Yucatan Peninsula whose larval stages and host plant (Dalechampia schottii, also endemic to the Yucatan Peninsula) were previously unknown.Conclusions/SignificanceThis investigation has revealed overlooked species in a well-studied museum collection of nymphalid butterflies and suggests that there is a substantial incidence of cryptic species that await full characterization. The utility of barcoding in the rapid identification of caterpillars also promises to accelerate the assembly of information on life histories, a particularly important advance for hyperdiverse tropical insect assemblages.

. 2012. Ensambles de aves diurnas a través de un gradiente de perturbación en un paisaje en el sureste de México. Acta Zoológica Mexicana (n. s.), 28(2): 237-269. RESUMEN. Con el objetivo de evaluar la diversidad de aves que se presentan en un paisaje del trópico mexicano, en el año 2008 se evaluó la riqueza, abundancia y distribución de las aves y sus gremios de forrajeo en ocho unidades del paisaje agrupadas en dos ecomosaicos. De las 218 especies identificadas, 207 estuvieron presentes en la estación seca y 119 en la de lluvias. Se encontró que la composición de avifauna difiere entre los ecomosaicos (a) matriz agropecuaria heterogénea y (b) bosque tropical perennifolio, así como entre las unidades de paisaje anidadas en ellos. La riqueza varió de 76 a 118 especies entre unidades del paisaje, mientras que el índice de diversidad de Shannon-Wiener resultó similar (de 3.20 a 4.44), y las comunidades de aves se distribuyeron equitativamente (Pielou: 0.71 a 0.91). En el paisaje se configura un escenario complementario entre ecomosaicos y una diversidad de aves muy alta, incluyendo especies importantes para la conservación como Tinamus major, Crypturellus soui, Crax rubra, Amazona farinosa, Odontophorus guttatus, Chondrohierax uncinatus, Platyrinchus cancrominus, Onycorhynchus coronatus y Manacus candei. Los gremios de forrajeo de aves se separan en función de las características ambientales de las unidades de paisaje por ejemplo, en los potreros con árboles dispersos predominan cazadoras desde percha y especies asociadas al ganado, mientras que en el bosque predominan los insectívoros que buscan sus presas en el suelo, corteza y follaje. Algunas especies como Lipaugus unirufus, Pipra mentalis y Schiffornis turdinus pueden funcionar como indicadoras ecológicas del bosque conservado, mientras otras como Sporophila americana, S. torqueola, Pitangus sulphuratus,

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Se evaluó si la coloración de las Nymphalidae frugívoras es un indicador de las unidades del paisaje. Se consideraron 4 condiciones de matriz agropecuaria (vegetación secundaria madura, vegetación secundaria joven, pastizales y cercos vivos) comparadas con 4 unidades de bosque (referente ecológico), en Tenosique, Tabasco, México. En cada unidad de paisaje se establecieron 10 trampas Van Someren-Rydon durante 5 días, aplicando 4 repeticiones. Se identificaron 63 especies, 58 en la matriz agropecuaria y 42 en el referente ecológico. Treinta y siete especies son compartidas, 21 asociadas a áreas agropecuarias y 5 solo del referente ecológico. La estructura de la vegetación afectó la abundancia y composición, pero no la riqueza de mariposas. Las comunidades de la matriz agropecuaria difirieron > 75% respecto al referente ecológico. Hubo correlación entre el color y el hábitat preferencial. Los patrones tigre y transparente (Danainae) se encontraron en el dosel cerrado. Con excepción de Adelpha (Limenitidinae) y las de color corteza (Biblidinae), las demás utilizan ampliamente el paisaje, destacando el tipo Hamadryas asociado a ambientes abiertos. El mosaico del paisaje estudiado de remanentes de bosque asociados a una matriz agropecuaria arbolada favorece la conservación del gremio de lepidópteros y mantiene una alta diversidad de las Nymphalidae frugívoras. Derechos Reservados © 2016 Universidad Nacional Autónoma de México, Instituto de Biología. Este es un artículo de acceso abierto distribuido bajo los términos de la Licencia Creative Commons CC BY-NC-ND 4.0.