BECAS
HILEVSKI LORETO Samuel
congresos y reuniones científicas
Título:
Preliminary report: Discovering the ancestral origin of Crocodylus in South America: an expedition to the amazing and complex Orinoco Delta
Autor/es:
GUALBERTO PACHECO-SIERRA; PABLO SIROSKI; MATTHEW SHIRLEY; SAMUEL HILEVSKI; RAFAEL ANTELO; ALVARO VELASCO; MYRIAM VENEGAS-ANAYA
Lugar:
Chetumal
Reunión:
Congreso; 26th Working Meeting CSG-IUCN. Chetumal, Mexico.; 2022
Institución organizadora:
SSC/IUCN Crocodile Specialist Group
Resumen:
In 1801, Alexander von Humboldt carried out an expedition to the Orinoco Delta, identifying the presence of Crocodylus intermedius. Two centuries later, Medem (1983) mentions that the Orinoco Delta is an area of exchange or hybrid zone between Crocodylus intermedius and Crocodylus acutus. However, no formal expeditions have been made to the Orinoco Delta to confirm the presence of both, or either, species in this amazing and complex environmental system. Evolutionarily, this area is of great relevance because it may be the zone of primary divergence of the most ancestral species of Crocodylus in South America and a potential hybrid zone between thetwo species present in Venezuela. The phylogenetic origin of both species is still unknown, as well as the reason for their distributional divergence: C. intermedius is restricted to freshwater habitats of the Orinoco River, while C. acutus is a coastal and estuarine species of the Atlantic Ocean and Caribbean. Our principal aim was to explore the Orinoco Delta to discover C. intermedius and C. acutus and, ultimately, test their evolutionary origins and possible ancestral hybridization or incomplete lineage sorting using molecular, morphometric, and ecological tools. During this work,we will also seek to understand the ethnozoographic relationship that local people (Waraos) have with these crocodylian species. Generally the interaction between wild populations of crocodiles and local communities can set the stage for conservation interventions and help actions for these species in their different distribution areas. This project was funding by National Geographic and the first stage is already finished.
