Peter Kovalik
Well-known member
Díaz Campo, Oscar Alexis (2024) Using physiological and molecular approaches to study micro- and macro-evolutionary patterns of selected waterbirds of the High Andes. Ph.D. dissertation, University of Miami.
Research Portal
Abstract
Waterbirds, a diverse group of habitat-specialist birds, are distributed unevenly across environmental gradients, including elevation. High-altitude environments present a range of challenges for vertebrate life, including cold, low humidity and decreased air pressure. Yet, many waterbirds thrive along steep elevational gradients along the Andes Mountains. Population trends of waterbirds are linked to the health and sustainable use of wetland ecosystems, and many species are currently threatened by human-driven and climate related impacts. So, unraveling spatial and temporal patterns of species evolution is crucial for understanding population dynamics, species success, and habitat conservation. In my dissertation, I studied micro- and macro-evolutionary patterns to explore the physiological and genetic responses to high altitude of the Andean endemic slate-colored coot (Fulica ardesiaca), as well as the diversification process of all modern flamingos (Phoenicopteridae), three of which are also endemic to the Andean region. For my first two chapters, I collected the most comprehensive morphometric and hematological data, as well as mitochondrial control region and partial autosomal genome sequencing data, to assess the phenotypic and genotypic divergence between low- and high-altitude populations of F. ardesiaca along the Peruvian Andes. My study found support for Bergmann’s and Allen’s rules in relation to variation in body size and culmen size across elevational and latitudinal gradients. It also revealed that polycythemia is not a necessary response to hypoxia for this species. Moreover, both genetic markers revealed spatial genetic structure between low- and high-altitude populations likely governed by genetic drift. Autosomal loci also revealed a high-altitude origin for Fulica ardesiaca populations in Peru (0.25 Mya), with secondary, recent colonization of coastal wetlands. For my last chapter, which concerns the study of the diversification of modern flamingos, using for the first time, whole genome sequencing data from relatively modern museum samples, I confirmed the existence of two main clades within the flamingo species tree: the deep-keeled clade (Phoenicopterus roseus, Phoenicopterus ruber, and Phoenicopterus chilensis) and the shallow-keeled clade (Phoenicoparrus andinus, Phoenicoparrus jamesi and Phoeniconaias minor), as previously proposed based on mandibular morphology. I also inferred the origin of modern flamingos to be more recent than previously recognized during the Pliocene period (3.7-4.1 Mya) and observed varying degrees of introgression across flamingo species. Finally, analyses of contemporary genomic diversity and demographic history in both F. ardesiaca and South American flamingos suggest that the increasing temperatures of the current interglacial period may not bode well for the evolutionary potential of these waterbirds inhabiting the high Andes.
Research Portal
Abstract
Waterbirds, a diverse group of habitat-specialist birds, are distributed unevenly across environmental gradients, including elevation. High-altitude environments present a range of challenges for vertebrate life, including cold, low humidity and decreased air pressure. Yet, many waterbirds thrive along steep elevational gradients along the Andes Mountains. Population trends of waterbirds are linked to the health and sustainable use of wetland ecosystems, and many species are currently threatened by human-driven and climate related impacts. So, unraveling spatial and temporal patterns of species evolution is crucial for understanding population dynamics, species success, and habitat conservation. In my dissertation, I studied micro- and macro-evolutionary patterns to explore the physiological and genetic responses to high altitude of the Andean endemic slate-colored coot (Fulica ardesiaca), as well as the diversification process of all modern flamingos (Phoenicopteridae), three of which are also endemic to the Andean region. For my first two chapters, I collected the most comprehensive morphometric and hematological data, as well as mitochondrial control region and partial autosomal genome sequencing data, to assess the phenotypic and genotypic divergence between low- and high-altitude populations of F. ardesiaca along the Peruvian Andes. My study found support for Bergmann’s and Allen’s rules in relation to variation in body size and culmen size across elevational and latitudinal gradients. It also revealed that polycythemia is not a necessary response to hypoxia for this species. Moreover, both genetic markers revealed spatial genetic structure between low- and high-altitude populations likely governed by genetic drift. Autosomal loci also revealed a high-altitude origin for Fulica ardesiaca populations in Peru (0.25 Mya), with secondary, recent colonization of coastal wetlands. For my last chapter, which concerns the study of the diversification of modern flamingos, using for the first time, whole genome sequencing data from relatively modern museum samples, I confirmed the existence of two main clades within the flamingo species tree: the deep-keeled clade (Phoenicopterus roseus, Phoenicopterus ruber, and Phoenicopterus chilensis) and the shallow-keeled clade (Phoenicoparrus andinus, Phoenicoparrus jamesi and Phoeniconaias minor), as previously proposed based on mandibular morphology. I also inferred the origin of modern flamingos to be more recent than previously recognized during the Pliocene period (3.7-4.1 Mya) and observed varying degrees of introgression across flamingo species. Finally, analyses of contemporary genomic diversity and demographic history in both F. ardesiaca and South American flamingos suggest that the increasing temperatures of the current interglacial period may not bode well for the evolutionary potential of these waterbirds inhabiting the high Andes.
