Neo-Darwinian explanations of organic evolution have settled on mutation as the principal factor in producing evolutionary novelty. Mechanistic characterizations have been also biased by the classic dogma of molecular biology, where only proteins regulate gene expression. This together with the rearrangement of genetic information, in terms of genes and chromosomes, was considered the cornerstone of evolution at the level of natural populations. This predominant view excluded both alternative explanations and phenomenologies that did not fit its paradigm. With the discovery of non-coding RNAs (ncRNAs) and their role in the control of genetic expression, new mechanisms arose providing heuristic power to complementary explanations to evolutionary processes overwhelmed by mainstream genocentric views. Viruses, epimutation, paramutation, splicing, and RNA editing have been revealed as paramount functions in genetic variations, phenotypic plasticity, and diversity. This article discusses how current epigenetic advances on ncRNAs have changed the vision of the mechanisms that generate variation, how organism-environment interaction can no longer be underestimated as a driver of organic evolution, and how it is now part of the transgenerational inheritance and evolution of species.

In the present study, the morphology, color pattern, chromosomal complement and aspects of meiosis in natural populations at the borders of the distributions of Mepraia gajardoi Frías et al and Mepraia spinolai (Porter) are described. The males of these bordering populations are brachypterous or macropterous, while females are always micropterous. Morphological and cytogenetic data indicated that the populations that border the distributions of M. gajardoi and M. spinolai, belong to a different species of parapatric origin.

The South American fruit fly Anastrepha fraterculus (Wiedemann) is a complex of cryptic species, the so-called “Anastrepha fraterculus complex”, for which eight morphotypes are currently recognized. A previous analysis of ITS1 in samples of the Anastrepha fraterculus complex, while revealing high distinctiveness among samples from different localities of South America, Central America, and Mexico, no direct association was made between sequence type and morphotype. In the present report, a correlated analysis of morphometry and ITS1 data involved individuals belonging to the same population samples. Although showing a low level of intra-populational nucleotide variability, the ITS1 analysis indicated numerous inter-population sequence type variants. Morphotypes identified by morphometric analysis based on female wing shape were highly concordant with ITS1 genetic data. The correlation of genetic divergence and morphological differences among the tested samples gives strong evidence of a robust dataset, thereby indicating the existence of various taxonomic species within the A. fraterculus complex. However, the data revealed genetic and morphological variations in some regions, suggesting that further analysis is still required for some geographic regions.

In central Chile, Rhagoletis brncici and R. conversa, can be found in sympatry, associated with the fruit of their native host plants: Solanum tomatillo and S. nigrum (Solanaceae), respectively. Third-stage larvae must emerge from its host in search of pupation sites, and during this period larvae must find an appropriate pupation microhabitat while avoiding predation and adverse abiotic factors. In this study, we explored whether these sympatric species differ in terms of the timing of their larval exit from the host fruit in search of pupation sites. Field-collected fruits from host plants were checked daily for larval emergence, within 24 h, under laboratory conditions, in order to determine the time of the event. We found that these species differed significantly in their diel larval emergence. For R. brncici, most larvae left the host fruit between late evening and past midnight, meanwhile larvae from R. conversa concentrated their peak of emergence near midnight and early morning. We discuss these findings in terms of the ecological and evolutionary implications of the temporal separation of larval emergence regarding the use of pupation sites, abiotic stress and risk of predation for these sympatric species.

Mepraia spinolai (Porter) is a vector of Trypanosoma cruzi that causes Chagas disease. Females are always wingless, but males may be winged or wingless. We determined by PCR the infection percentage with T. cruzi of M. spinolai adults and nymphs in domestic, peridomestic, and wild collections, in different regions of Chile. In all regions, winged males were more abundant than females and wingless males. Winged males collected inside houses were less parasitized than were those from peridomestic and wild environments. Although winged males of M. spinolai have comparatively low levels of infection, this segment may still represent the greatest vector threat in this species for transmission of T. cruzi to humans and other vertebrates in domestic, wild, and peridomestic habitats. Winged males represent the dispersive form of this species that invades human dwellings. Feeding deprivation resulting from the time required to find a food source and to search for reproductive females could explain the lower infection rates (negatives) of winged males collected from inside houses in comparison with winged males collected from peridomestic and wild habitats.

The origin of genes is one of the most enigmatic events in the origin of life. It has been suggested that noncoding (nc) RNA was probably a precursor in the formation of the first polypeptide, and also at the origin of the first manifestation of life and genes. ncRNAs are also becoming central for understanding gene expression and silencing. Indeed, before the discovery of ncRNAs, proteins were viewed as the major molecules in the regulation of gene expression and gene silencing; however, recent findings suggest that ncRNA also plays an important role in gene expression. Reverse transcription of RNA viruses and their integration into the genome of eukaryotes and also their relationship with the ncRNA suggest that their origin is basal in genome evolution, and also probably constitute the first mechanism of gene regulation. I am to review the different roles of ncRNAs in the framework of gene evolution, as well as the importance of ncRNAs and viruses in the epigenesis and in the non-Mendelian model of heredity and evolution.