Current Research
Sloths as a study system
Sloths are an interesting case study as they represent a combination of low extant diversity, extremely high levels of extinction, and debated phylogenetic interrelationships between fossil and extant taxa. Sloths possess unique morphological and physiological traits that depart from the typical mammalian bauplan. Their "weirdness" makes them the perfect system to test many truisms established on more "conventional" mammals. We are interested in different biological aspects of sloth evolution. Our work ranges from phylogenetic analyses to understand their evolutionary and biogeographic patterns, to controlled feeding experiments to assess physiological and ecological aspects of their biologies.
Sloths are an interesting case study as they represent a combination of low extant diversity, extremely high levels of extinction, and debated phylogenetic interrelationships between fossil and extant taxa. Sloths possess unique morphological and physiological traits that depart from the typical mammalian bauplan. Their "weirdness" makes them the perfect system to test many truisms established on more "conventional" mammals. We are interested in different biological aspects of sloth evolution. Our work ranges from phylogenetic analyses to understand their evolutionary and biogeographic patterns, to controlled feeding experiments to assess physiological and ecological aspects of their biologies.
Credit: Falco Rivera
Feeding and trophic ecology
Understanding the feeding ecology of both extinct and extant animals is crucial for assessing palaeoclimate, vegetation structure, habitat use, niche partitioning, and predator-prey interactions in fossil ecosystems. Stable isotope geochemistry is a powerful tool for reconstructing ancient ecologies and ecosystems because it is independent of morphology and reflects dietary ecology. However, information from stable isotope methods is limited by poorly experimentally constrained assumptions regarding diet-tissue fractionations across organisms. Through experimental analysis of Neotropical mammals never before assessed, my lab aims to identify and understand patterns of isotope fractionation across different taxonomic groups.
Understanding the feeding ecology of both extinct and extant animals is crucial for assessing palaeoclimate, vegetation structure, habitat use, niche partitioning, and predator-prey interactions in fossil ecosystems. Stable isotope geochemistry is a powerful tool for reconstructing ancient ecologies and ecosystems because it is independent of morphology and reflects dietary ecology. However, information from stable isotope methods is limited by poorly experimentally constrained assumptions regarding diet-tissue fractionations across organisms. Through experimental analysis of Neotropical mammals never before assessed, my lab aims to identify and understand patterns of isotope fractionation across different taxonomic groups.
Credit: Illustration: Jorge Blanco
Tropical Paleontology
Our different projects have led to the recovery of many new fossil faunas from poorly known regions in South America (from the Andean highlands to tropical lowlands), with numerous publications and research projects mostly centered on the evolution of pan- and proto-Amazon ecosystems and the Andean plateau from both biological and geological perspectives (see list of publications).
Our different projects have led to the recovery of many new fossil faunas from poorly known regions in South America (from the Andean highlands to tropical lowlands), with numerous publications and research projects mostly centered on the evolution of pan- and proto-Amazon ecosystems and the Andean plateau from both biological and geological perspectives (see list of publications).
Credit: J. Tejada
Evolutionary Ecology
My lab aims to understand how biological, climatic, and geological processes have influenced and shaped the ecological evolution of mammals and other vertebrates in the Amazon. Despite the Amazon rainforest hosting the world's highest mammalian species richness, we have limited knowledge about niche structure and ecological roles of Amazonian mammalian communities over time. This knowledge gap extends to other organisms awaiting study in the region. Existing generalizations about closed-canopy rainforest mammalian communities have primarily been based on African ecosystems. Through our research in western Amazonia, a region that has been severely understudied, we have identified differences in the ecological structure of mammals compared to analogous closed-canopy rainforests.
My lab aims to understand how biological, climatic, and geological processes have influenced and shaped the ecological evolution of mammals and other vertebrates in the Amazon. Despite the Amazon rainforest hosting the world's highest mammalian species richness, we have limited knowledge about niche structure and ecological roles of Amazonian mammalian communities over time. This knowledge gap extends to other organisms awaiting study in the region. Existing generalizations about closed-canopy rainforest mammalian communities have primarily been based on African ecosystems. Through our research in western Amazonia, a region that has been severely understudied, we have identified differences in the ecological structure of mammals compared to analogous closed-canopy rainforests.
Credit: P.-O. Antoine
Comparative physiology and paleophysiology
Understanding the physiological processes underlying the isotopic variability observed in modern organisms is the first necessary step to attempt a thorough and cautious interpretation of the geochemical signals preserved in the fossil record. We address this topic by conducting controlled feeding experiments with zoological animals and analyses with museum specimens with detailed accession information.
Understanding the physiological processes underlying the isotopic variability observed in modern organisms is the first necessary step to attempt a thorough and cautious interpretation of the geochemical signals preserved in the fossil record. We address this topic by conducting controlled feeding experiments with zoological animals and analyses with museum specimens with detailed accession information.
Credit: J. Tejada