El propóleos es un producto elaborado por las abejas, que se caracteriza por poseer propiedades antioxidantes y antimicrobianas, las cuales son atribuidas a la presencia de compuestos polifenólicos, principalmente flavonoides. Estos compuestos son de bajo peso molecular y en su estructura química contienen un número variable de grupos hidroxilos. Varios investigadores han reportado que los mecanismos antioxidantes propuestos para estos grupos son mediante secuestro de radicales libres, o actuando como substrato para radicales, tales como superóxido e hidroxilo, y quelación de iones metálicos. Mientras que el mecanismo antimicrobiano involucra la inhibición de ácidos nucleicos y degradación de la membrana citoplasmática.

Eight propolis samples from the eastern edge of the Sonoran Desert were collected at two sites (Pueblo de Álamos and Rancho Viejo, located at Ures, Sonora, Mexico) during two seasons of the year (winter and summer, 2012 and 2013) and analyzed using palynological methods in order to determine which plants were visited by bees in order to collect raw material (resins, wax and pollen) to form propolis. The pollen analysis identified a total of 42 pollen types. Six samples of propolis were bifloral (summer and winter samples) and two multifloral (winter). Mimosa distachya var. laxiflora and Prosopis velutina were considered characteristic pollen types, composing 15 to 45% of total pollen sums.

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Priority Marine Regions (PMR) are important areas for biodiversity conservation in the Northwest Pacific Ocean in Mexico. The oceanographic dynamics of these regions are very important to understand their variability, generate analyses, and predict climate change trends by generating an adequate management of marine resources and their ecological characterization. Chlorophyll a (Chl a) is important to quantify phytoplankton biomass, consider the main basis of the trophic web in marine ecosystems, and determine the primary productivity levels and trends of change. The objective of this research is to analyze the oceanographic variability of 24 PMR through monthly 1-km satellite image resolution Chl a data from September 1997 to October 2018. A cluster analysis of Chl a data yielded 18 regions with clear seasonal variability in the Chl a concentration in the South-Californian Pacific (maximum values in spring-summer and minimum ones in autumn-winter) and Gulf of California (maximum values in winter-spring and minimum ones in summer-autumn). Significant differences (p < 0.05) were observed in Chl a concentration analyses for each one of the regions when climate patterns—El Niño/La Niña Southern Oscillation (ENSO) and normal events—were compared for all the seasons of the year (spring, summer, autumn, and winter).

During the last glacial termination, the climate system experienced intense global variations whose causes and impacts are not fully defined, particularly for low latitudes. The northwestern Mexico Sky Islands present a climate‐sensitive ideal setting to record palaeoecological and palaeoclimatic changes due to their physiographic complexity and location in the ecotone between temperate and tropical ecosystems. High‐resolution pollen analysis and a detailed sedimentological study were conducted at the Ciénega Tonibabi tropical thorn scrub site. The 15 540–0 cal a bp nearly continuous record shows that the North Atlantic Ocean did have a cold and humid climatic influence during the glacial stages of the end of the Pleistocene, including a sharp pulse during the Younger Dryas. However, a shift to the Pacific Ocean influence occurred during the Holocene, which led to the development of the El Niño conditions prevailing today. Colder and warmer phases follow one another with higher or lower winter precipitation, including a sharp Bølling–Allerød and development and intensification of the North American monsoon. They are reflected in hydrological changes as well as in the advances, retreats and intermingling of coniferous forests and tropical thorn scrub.