Mónica Nova Delgado

El Tenebrio molitor (TM) es un insecto con alto valor nutricional y propiedades bioactivas. Su cría es más sostenible que la ganadería tradicional, genera menos emisiones de gases de efecto invernadero y consumen menos agua, tierra y energía. Asimismo, se alinea con los principios de economía circular al utilizar residuos orgánicos para convertirlos en proteínas y sus excretas (frass) en biofertilizante. Este proyecto tiene como objetivo establecer un semillero de investigación en el INFOTEP de San Juan del Cesar (La Guajira), enfocado en la cría de TM y la aplicación de sus subproductos. El semillero investiga el uso del frass en cultivos de ahuyama y la caracterización de sustratos orgánicos como fuentes de alimentación para el insecto. La metodología emplea un enfoque experimental con la cría controlada del TM y un enfoque participativo, mediante la implementación de talleres prácticos que promuevan la entomocultura. Los resultados esperados incluyen el aprendizaje activo y el desarrollo de competencias académicas y sociales de los estudiantes, a través de procesos que integran el conocimiento técnico y científico. Además, se espera una mejora directa en la productividad agrícola de las comunidades locales, al utilizar frass como biofertilizante. La consolidación de este semillero fortalece la formación de profesionales innovadores y generará nuevas líneas de investigación sobre el TM, con el objetivo de aplicar sus resultados a largo plazo en la agroindustria local, y así contribuir a la creación de modelos sostenibles para la producción de alimentos y el uso eficiente de los recursos en la agricultura.

Molars are highly integrated biological structures that have been used for inferring evolutionary relationships among taxa. However, parallel and convergent morphological traits can be affected by developmental and functional constraints. Here, we analyze molar shapes of platyrrhines in order to explore if platyrrhine molar diversity reflects homogeneous patterns of molar variation and covariation. We digitized 30 landmarks on mandibular first and second molars of 418 extant and 11 fossil platyrrhine specimens to determine the degree of integration of both molars when treated as a single module. We combined morphological and phylogenetic data to investigate the phylogenetic signal and to visualize the history of molar shape changes. All platyrrhine taxa show a common shape pattern suggesting that a relatively low degree of phenotypic variation is caused by convergent evolution, although molar shape carries significant phylogenetic signal. Atelidae and Pitheciidae show high levels of integration with low variation between the two molars, whereas the Cebinae/Saimiriinae, and especially Callitrichinae, show greater variation between molars and trend toward a modular organization. We hypothesize that biomechanical constraints of the masticatory apparatus, and the dietary profile of each taxon are the main factors that determine high covariation in molars. In contrast, low molar shape covariation may result from the fact that each molar exhibits a distinct ecological signal, as molars can be exposed to distinct occlusal loadings during food processing, suggesting that different selective pressures on molars can reduce overall molar integration.

The phylogenetic position of many fossil platyrrhines with respect to extant ones is not yet clear. Two main hypotheses have been proposed: the layered or successive radiations hypothesis suggests that Patagonian fossils are Middle Miocene stem platyrrhines lacking modern descendants, whereas the long lineage hypothesis argues for an evolutionary continuity of all fossil platyrrhines with the extant ones. Our geometric morphometric analysis of a 15 landmark-based configuration of platyrrhines’ first and second lower molars suggest that morphological stasis may explain the reduced molar shape variation observed. Platyrrhine lower molar shape might be a primitive retention of the ancestral state affected by strong ecological constraints throughout the radiation of the main platyrrhine families. The Patagonian fossil specimens showed two distinct morphological patterns of lower molars, Callicebus—like and Saguinus—like, which might be the precursors of the extant forms, whereas the Middle Miocene specimens, though showing morphological resemblances with the Patagonian fossils, also displayed new, derived molar patterns, Alouatta—like and Pitheciinae—like, thereby suggesting that despite the overall morphological stasis of molars, phenotypic diversification of molar shape was already settled during the Middle Miocene.

Morphometric variation of biological structures has been widely used to determine taxonomic affinities among taxa, and teeth are especially informative for both deep phylogenetic relationships and specific ecological signals. We report 2-dimensional geometric morphometrics (GM) analyses of occlusal crown surfaces of lower molars (M₁, n = 141; M₂, n = 158) of cercopithecoid primate species. A 12-landmark configuration, including cusp tips and 8 points of the molar crown contour, were used to evaluate patterns of variation in lower molar shape among cercopithecoid primates and to predict the taxonomic attribution of 2 archaeological macaques from Roman time periods. The results showed that the lower molar shape of cercopithecoid primates reflects taxonomic affinities, mostly at a subfamily level and close to a tribe level. Thus, the cusp positions and crown contour were important elements of the pattern related to interspecific variation. Additionally, the archaeological specimens, attributed to Macaca sylvanus based on osteological information, were classified using the GM molar shape variability of the cercopithecoid primates studied. The results suggest that their molar shape resembled both M. sylvanus and M. nemestrina, and species attribution varied depending on the comparative sample used.