Great genome size (GS) variations described in desert-specialist octodontid rodents include diploid species ( Octomys mimax and Octodontomys gliroides ) and putative tetraploid species ( Tympanoctomys barrerae and Pipanacoctomys aureus ). Because of its high DNA content, elevated chromosome number, and gigas effect, the genome of T. barrerae is claimed to have resulted from tetraploidy. Alternatively, the origin of its GS has been attributed to the accumulation of repetitive sequences. To better characterize the extent and origin of these repetitive DNA, self-genomic in situ hybridization (self-GISH), whole-comparative genomic hybridization (W-CGH), and conventional GISH were conducted in mitotic and meiotic chromosomes. Self-GISH on T. barrerae mitotic plates together with comparative self-GISH (using its closest relatives) discriminate a pericentromeric and a telomeric DNA fraction. As most of the repetitive sequences are pericentromeric, it seems that the large GS of T. barrerae is not due to highly repeated sequences accumulated along chromosomes arms. W-CGH using red-labeled P. aureus DNA and green-labeled O. mimax DNA simultaneously on chromosomes of T. barrerae revealed a yellow-orange fluorescence over a repetitive fraction of the karyotype. However, distinctive red-only fluorescent signals were also detected at some centromeres and telomeres, indicating closer homology with the DNA sequences of P. aureus. Conventional GISH using an excess of blocking DNA from either P. aureus or O. mimax labeled only a fraction of the T. barrerae genome, indicating its double genome composition. These data point to a hybrid nature of the T. barrerae karyotype, suggesting a hybridization event in the origin of this species.

Academic production about the main Chilean cities exceeds the existing documentation on intermediate cities, though they have shown interesting trends patterns in recent years which have changed the urban system in Chile. This paper aimed to analyze the urban growth processes in Chilean intermediate cities using Temuco as a case study. It begins with an historical look at the city and then mentions that in the last decades this kind of cities have undergone new forms of segregation associated to real estate activities such as private communities, rural residential properties and new localization of services which have resulted in a fragmentation of urban space, a phenomenon reinforced by the consolidation of some satellite cities. At the same time, many urban problems associated to poverty, like a standstill of the regional economy and environmental pollution have appeared, jeopardizing the sustainability of these spaces, questioning current development parameters. The article ends considering the future challenges in Temuco’s urban development.

Worldwide, but particularly in Latin America, private protected areas (PPAs), including in mountain areas, have become increasingly numerous. In some Latin American countries, PPAs complement the public protected areas to a significant degree. Beneficiaries of these private protection initiatives, which often close gaps in fragmented biomes, may be governments or eco-tourism operators. Drawbacks of PPAs are the lack of clear definitions and ownership, the absence of suitable management, green grabbing, and limited government support. This article gives an overview of PPAs in mountain regions and presents the most important literature published so far.

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La sustentabilidad de la agricultura familiar (AF) ha cobrado interés en el actual escenario de cambio ambiental global. En este contexto, los sistemas agrícolas de montaña son uno de los menos estudiados, a pesar que permiten el manejo predial manteniendo prácticas tradicionales. La investigación analiza mediante la metodología MESMIS, el grado de sustentabilidad de predios de AF con enfoque agroecológico y convencional, con el fin de visibilizar el aporte de la AF con enfoque agroecológico a la sustentabilidad predial en territorios de montaña, en particular el caso de Curarrehue, en la Araucanía Andina Chilena. Los resultados muestran que la utilización de prácticas agroecológicas, basadas en los conocimientos locales, son mecanismos que permiten un mejor desempeño de las unidades familiares en los ámbitos ambiental, económico y social.