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In this study we focused on urban bird diversity across Mexico, a megadiverse country, with a special focus on the relative role of urban greenspaces and heavily-built sites. We considered a country-wide approach, including 24 different sized Mexican cities. Our aims were to describe the urban bird diversity in focal cities and further assess the relationships between it and the biogeographic region where cities are located, their size, elevation, and annual rainfall. Additionally, we evaluated differences in the functional composition of bird communities in both studied urban scenarios (i.e., urban greenspaces, heavily-built sites). Our results confirm that urban greenspaces are home to a large proportion of species when contrasted with heavily-built sites. While total species richness and species richness of greenspaces were related with the cities' biogeographic region -with higher species richness in the Neotropical region and Transition Zone-, the relationship did not hold true in heavily-built sites. We found that annual rainfall was negatively related to bird richness in heavily-built sites, suggesting that species from arid systems can be more tolerant to urbanization. Regarding the bird functional group assessment, results show a clear differentiation between the functional groups of greenspaces and those of heavily-built sites, with granivores and omnivores associated with the latter and a highly diverse array of functional groups associated with urban greenspaces., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2020. Published by Elsevier B.V.)

To establish seasonal trends in infection and maturity of Fasciola hepatica in cattle in relation to macroclimatic factors, 2730 condemned livers were examined from March 1989 to February 1992. Livestock came from Jalapa, Tacotalpa and Teapa, all municipalities in Tabasco State. Flukes were collected monthly and separated into three different maturation stages. Mean numbers of flukes collected were determined. The analysis of the maturation stages detected in cattle showed: (a) F. hepatica matured throughout the year at all three sites; (b) the greatest mean fluke's burdens were found in Jalapa and the lowest in Teapa; large parasite populations were significantly higher from February to September than in July and/or August; (c) persistence of mature, gravid F. hepatica indicated that parasite eggs are shed throughout the year; (d) recruitment of F. hepatica occurred throughout the year with two major periods of infection, the first and main period during the dry season (from February to June), and a second minor infection period, during the rainy season (from August to October); (e) a close relationship was observed between the seasonal infection pattern in cattle and the seasonal infection pattern in snails, as well as fluctuations in the snail population according to rainfall and temperature variation.