Browsing by Author "Hinojosa, Luis Felipe"

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    Genetic and phenotypic diversity in 2000 years old maize (Zea mays L.) samples from the Tarapaca region, Atacama Desert, Chile
    (2019) Vidal Elgueta, Alejandra Isabel; Hinojosa, Luis Felipe; Pérez Trautmann, María Fernanda; Peralta, Gioconda; Uribe Rodriguez, Mauricio
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    Spatial patterns of congruence or mismatch between taxonomic, functional, and phylogenetic diversity and endemism of perennial flora along the aridity gradient of Chile
    (2024) Poch, Paola; Poulin, Elie; Perez, Maria Fernanda; Peralta, Gioconda; Hinojosa, Luis Felipe
    Introduction: Understanding the relationships between taxonomic, functional, and phylogenetic diversity and endemism across environmental gradients is essential for elucidating the eco-evolutionary mechanisms that shape local plant communities. Methods: A database was compiled from field surveys, national herbarium records, and virtual records of perennial plant specimens collected in the aridity gradient of northern Chile, between 18 and 32 degrees S. A large-scale dated phylogeny of available perennial plants was used, and 11 functional traits were selected to construct a dendrogram using the Unweighted Pair-Group Method with Arithmetic Mean (UPGMA) method for the species present in our database. We calculated spatial patterns of a-diversity, including taxonomic (TD), functional (FD), and phylogenetic (PD) diversity, as well as weighted (WE), functional (FE), and phylogenetic (PE) endemism. We used multiscale geographically weighted regression (MGWR) to identify spatial congruencies and discrepancies among these dimensions and to test different eco-evolutionary processes. Results: The diversity indices TD, FD and PD showed similar geographic patterns (R2 > 0.93), with lower diversity observed in absolute desert regions. The pattern of weighted endemism (WE) showed a weak association with functional endemism (FE) and phylogenetic endemism (PE) (local R2 < 0.48). The regions with lower FD or PD than expected given the TD (i.e. FDWE and PE>WE), they are found in arid, high Andean and transitional zones, at different altitudes, which would indicate a greater presence of phylogenetic lineages and species with morpho-functional traits related to extreme environmental conditions and transitional biomes (arid-semiarid). Discussion: These spatial discrepancies suggest different eco-evolutionary drivers between the dimensions of diversity and endemism (taxonomic, functional, and phylogenetic). Areas of high diversity and high endemism do not necessarily coincide, and both should be addressed by conservation efforts.
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    Speciation and evolution of growth form in Adesmia D. C. (Dalbergieae, Fabaceae): the relevance of Andean uplift and aridification
    (2024) Perez, Fernanda; Lavandero, Nicolas; Hinojosa, Luis Felipe; Cisternas, Mauricio; Araneda, Daniela; Pinilla, Nicolas; Moraga, Valeska
    The Andean uplift and the concomitant aridification drove the rapid diversification of several plant lineages that were able to colonize warmer and drier habitats at low elevations and wetter and colder habitats at high elevations. These transitions may be facilitated by shifts in plant strategies to cope with drought and cold, which in turn can trigger episodes of accelerated species diversification. Here, we used four nuclear DNA markers to infer phylogenetic relationships of 80 Adesmia species of annuals, perennial herbs, shrubs and small shrubs that occur in Chile and Argentina. We reconstructed ancestral states for area, climatic niche and growth form to explore how Andean uplift and aridification promoted Adesmia diversification. We also performed logistic and linear regression analyses between different components of growth form (life span, woodiness and plant height) and climate. Finally, we estimated speciation rates across the phylogeny. Our results suggest that the ancestor of Chilean Adesmia was a perennial herb that probably originated in the high Andes of northern and central Chile. The low elevations of Central Chile were colonized in the late Miocene, whereas the high latitudes of Patagonia and the hyperarid coastal Atacama Desert were colonized repeatedly since Pliocene by lineages with different growth forms. Multiple and bidirectional transitions between annual and perennial habits and between herbaceous and woody habits were detected. These shifts were not correlated with climate, suggesting that the different growth forms are alternative and successful strategies to survive unfavorable seasons of both desert and high Andes. Net diversification analysis indicated a constant rate of diversification, suggesting that the high species diversity of Adesmia that occur in Chile is due to a uniform speciation process rather than to accelerated episodes of speciation.