The actual knowledge about the freshwater algae of Mexico is very uneven from various points of view, despite its recognized potential as indicators of environmental conditions and to be the basal part of trophic chains in aquatic environments. The largest…

Surfaces of buildings at the archaeological site of Palenque, Mexico, are colonized by cyanobacteria that form biofilms, which in turn cause aesthetic and structural damage. The structural characterization and species composition of biofilms from the walls of one of these…

Diabetes mellitus is a syndrome which affects more and more people in all countries over the world. In Mexico, it is commonly treated with herbal extracts. Such treatment may be of considerable benefit especially during the early stages of the…

Early in the twentieth century it was shown that Mendel's laws apply to plants and animals and that genes reside on chromosomes. In the 1950s the double-helix model of DNA inaugurated the molecular biology era, which culminated at the end…

A new terrestrial species of Pseudoeurycea is described from the mountains of the Mixteca region of Oaxaca. Compared with other members of the genus, the new species is relatively slender and short-legged. The background color of the dorsum of this…

A new tertiary stibine and bismuthine containing C-heterocyclic selenophene ring have been synthesized. Tris(2-selenophenyl)stibine (1) and tris(2-selenophenyl) bismuthine (2) and characterized by IR, MS, H-1, C-13, COSY, HETCOR NMR spectroscopy. Crystal structures of stibine and bismuthine have been determined. In…

In various species of crayfish it has been proposed that different extra-retinal photoreceptors and pacemakers could be involved in the photo entrainment mechanisms. The identity of the neural structures responsible for this phenomenon is not known. The objective of this…

While birdsong is a model system for animal communication studies, our knowledge is derived primarily from the study of only one sex and is therefore incomplete. The study of song in a role-reversed species would provide a unique opportunity to…

For the first time for Mexican mycobiota the genus Cerinomyces Mar. is reported with the species C lagerheimii (Pat.) McNabb. This species only have been found in Ecuador (type locality), Brasil, United States and Venezuela. A review of different specimens…

In 1950, Tinbergen described the elicitation of offspring begging by the red spot on the bill of parent gulls, and this became a model system for behavioural studies. Current knowledge on colour traits suggests they can act as sexual signals…