My research is collaborative, integrative, and covers a wide-range of subjects, such as hypothesis-testing on the origin of species and trait diversity, phylogenetic inference, taxonomy, biogeography, natural history, and conservation.
DISCOVERY AND DESCRIPTION OF GLOBAL BIODIVERSITY
Taxonomy and systematics are the foundation of all biological sciences, and a proper understanding of the natural world is necessarily linked to the advance of knowledge in classification and the discovery/description of biodiversity. One of the crucial elements of my research program is a continuous effort to conduct revisionary taxonomic work and the integrative use of genetic and phenotypic data to search for cryptic diversity within broadly distributed taxa . My current taxonomic work is focused primarily on Neotropical frogs with occasional contributions in other vertebrate groups, such as squamate reptiles (especially lizards in the Gymnophthalmidae family), fish, birds and insects.
Throughout my career I have participated in large expeditions to remote sites, which resulted in the collection of thousands of specimens and associated data (e.g., tissue samples, audiovisual material). These expeditions have also resulted in the discovery of dozens of new species of animals, many of which I have named or helped named throughout the years (see complete list of taxa named at end of Curriculum Vitae).
I will continue to study and document biodiversity in the Neotropics (with a focus in Amazonia), but I will also support and collaborate on initiatives to accelerate species discovery and taxonomic work in other critical areas of the globe.
New Species Discovered and Named
Espécie descoberta na Floresta Nacional de Pau Rosa, Amazonas, Brasil. Nomeada em homenagem ao lendário monstro amazônico "mapinguari"
COMPARATIVE BIOLOGY AND EVOLUTION
PHYLOGENETIC SYSTEMATICS: THEORY AND PRACTICE
I am broadly interested in practical and conceptual issues associated with phylogenetic inference of large and complex datasets, which often include the combination of genetic and phenotypic characters (Peloso et al. 2011, Amer. Mus. Novitat.; Orrico et al. 2020, Cladistics). For example, I use empirical analyses of data from non-model organisms to investigate how phylogenetic inference is influenced by the nuances of taxon and character sampling (e.g., Carvalho et al. 2016, Am. Mus. Novit; Peloso et al. 2016, Cladistics).
For my work on the systematics and evolution of the frog family Microhylidae, I used a NGS method (target enrichment) to obtain a large genetic dataset for a phylogenetic inference of the group. Microhylidae is globally distributed and one of the biggest and most diverse amphibian clades—although the monophyly of the family is broadly accepted, its internal relationships remain largely contentious. I have shown that even with a substantial genomic dataset, these problematic nodes remain volatile to variations in amount of data included, as well as to methods used for sequence alignment and phylogenetic inference (Peloso et al. 2016, Cladistics). I am currently working on a larger, combined genomic (including NGS data) and phenotypic (including CT data), dataset to infer how the use of anatomical and behavioral data will influence recovery and support for unstable nodes of the phylogeny.
Even with a considerable increase in genomic data some relationships remain uncertain, but preliminary data suggests that inclusion of a densely sampled phenotypic matrix is able to consistently solve some of these relationships with high statistical support. In another work, together with a M.Sc. student, we used a mix of DNA sequences and anatomical data (osteology characters obtained mostly from CT scans) to infer the impact of missing data and the role of implied character weighting in the phylogeny of a Neotropical lizard family (Alopoglossidae) (Morales et al. 2020, Cladistics). In both these studies, we documented empirically that analytical methods and source of evidence have a huge impact in the phylogeny, in its derived taxonomy, and in subsequent interpretation of biological phenomena, such as biogeography and trait evolution.
More recently, in collaboration with amphibian specialists from all over the world, we assembled a comprehensive genomic dataset to infer the phylogeny and divergence time estimates for the whole Amphibia (Hime et al. 2020, Syst. Biol.). Our results clarify several contentious relationships and, surprisingly, report younger origin and diversifications then previously reported for many lineages. We also provide some insights into the sources, magnitudes, and heterogeneity of support across loci in phylogenomic data sets.
I am interested in using phylogenies to test hypotheses in evolution and biogeography. I am particularly interested in understanding how landscape evolution and the appearance of key morphological or behavioral traits have shaped diversification in amphibians.
The question of how animals and plants have repeatedly “conquered” terrestrial environments has puzzled biologists for centuries. Amphibians are widely known for a stereotyped dependence on water for reproduction (aquatic eggs and tadpoles). However, many lineages evolved some independence from water bodies, culminating in total liberty from an aquatic environment for breeding and development (i.e., terrestrial eggs and no larval phase). Concomitant to the adaptations in reproductive biology are morphological adaptations to their lifestyle, such as loss of bones (due to miniaturization), multiple appearances of finger disks and bone elongation (for arboreality), and development of vertebral crests (possibly related to fossoriality). I have long been interested in investigating correlations between phylogeny, reproductive mode evolution and morphology in amphibians. I have studied this correlation in the microhylid genus Chiasmocleis (broadly distributed in South America), and recovered a strong association between miniaturization and terrestriality in this clade (Peloso et al. 2014, Bul. Amer. Mus. Nat. Hist.). We later showed that miniaturization is also correlated with a range of anatomical specializations in the group (De Sá et al. 2019, Mol. Phyl. Evol.).
I continue to study phenotypic evolution in Microhylidae, in the last few years have compiled a large genomic dataset together with representative CT-scans of several species in the group to infer correlates between phylogenetic diversity and ecological and phenotypic disparity. A part of this dataset was recently analyzed with collaborator Dr. Antoine Fouquet, where we found phylogenetically correlated phenotypes that emerged concomitantly with dispersals during the Miocene, and possibly represent adaptations to different habitats, such as soils with different physical properties.
Biogeography and Phylogeography
In recent years, I have become more interested in investigating geological and ecological processes driving amphibian and reptile diversification in the Neotropics. To achieve this, I use a combination of biogeography and statistical phylogeography methods to address the timing and mode of diversification in these groups. Initial findings suggest that some common patterns of diversification found in other Neotropical vertebrate groups do not widely apply to the amphibian groups we investigated. For example, in two unrelated amphibian genera with disjunct populations in the Amazon and Atlantic rainforests, our time estimate suggests that past connections between the two biomes is considerably older (early Miocene) than ages estimated for connections in birds and mammals (usually late Miocene to Pleistocene) (Pirani, Peloso et al. 2019, Mol. Phyl. Evol.; De Sá et al. 2019, Mol. Phyl. Evol.). Another important result, obtained in a comparative analysis of effectiveness of major Amazonian rivers in creating barriers to geneflow in amphibians and reptiles, is that not all major rivers are definite vicariant barriers, and that the divergence process indeed varies across time, space and species (Pirani et al. 2019, J. Biog.).
Despite a promising career in evolutionary biology, I did not feel entirely fulfilled professionally until I got more engaged with hands-on conservation initiatives, about five years ago. I have long been aware of the importance of conservation biology and how it is interlinked with field biology and taxonomy. Even before I started my PhD, I was already involved in conservation initiatives, and in 2010 I published a single authored essay/paper about the conservation of amphibians in the Brazilian Amazonia. Back then, taxonomic knowledge on Amazonian amphibians was a lot more incipient, and this reflected in the fact that very few (only three) amphibians were considered threatened with extinction. At the occasion, I highlighted the importance of concentrated efforts in taxonomy to promote a better overview of conservation status of amphibian populations:
“We cannot assess the true status of conservation of the amphibian biota in Amazonia
with our current taxonomic and biogeographic knowledge fir this mysterious, yet fascinating region”
(Peloso 2010, Papéis Avulsos de Zoologia.)
Since then, dozens of new amphibians were described in Amazonia and biogeographic knowledge within the region advanced enormously. Consequentially, a lot more taxa have been properly evaluated and multiple species are now considered threatened with extinction, including potential cases of actual extinction. My experience with this topic is very personal—three of the species I discovered and named, after that 2010 article was published, were considered threatened with extinction (two from Amazonia, and one, from the Atlantic Rainforest. Over the years I felt more and more compelled to get involved with hands-on/action-based conservation.
In 2018 I founded the ‘Documenting Threatened Species’ project (DoTS, www.projetodots.org), together with conservation geneticist Gui Becker (Penn State University) and conservationist Ibere Machado (IUCN’s Amphibian Specialist Group, Red List Authority-Brazil). DoTS is a bold initiative to study, document and generate awareness about endangered species in Brazil. It’s first phase focused on highly endangered amphibian species and was highlighted over multiple media channels (e.g., National Geographic and BBC), consequently introducing several of these extremely rare species to a global audience. Our team collected images, natural history data, and skin swab samples from threatened taxa we found over the course of seven expeditions across Brazilian biomes. This work will provide the first screening of the frog killing fungus Batrachochytrium dendrobatidis in natural populations of multiple endangered species.
As additional examples of my involvement in spearheading conservation initiatives, I am the Director of Strategic Planning for a Brazilian non-profit (Instituto Boitatá) and member of the Atelopus Survival Initiative (ASI).
Instituto Boitatá is focused on animal conservation and education, and we develop hands-on and field-based projects, and education initiatives in schools and public parks throughout Brazil. My role in the institute is to identify and develop strategic partnerships, to apply for grants, and oversee ongoing conservation projects.
On the other hand ASI is a collaborative effort of individuals and institutions from different countries dedicated to the conservation of Harlequin Toads (genus Atelopus). Atelopus are among the most endangered groups of vertebrates in the World, over 75% of its species threatened with extinction, with at least 40 species have not been seen since the early 2000 (although only four are considered formally extinct). As a member of ASI, I helped secure funding from National Geographic Society that will allow a large group of scientists, artists, and storytellers to meet in the field in Colombia to discuss and develop conservation strategies for Harlequin Toads.
I also collaborate with the International Conservation Fund of Canada in one of their flagship programs, the Kayapó Project, which focuses in empowering the Kayapo indigenous people of Amazonian Brazil to continue to protect over nine million hectares of their lands. Within the project, I co-teach an international field course hosted by a mixture of Brazilian, Canadian and U.S. partners, and conducted inside Kayapo territory (see details on Teaching Statement).
My involvement in conservation is rapidly expanding, and with each new accomplishment and partnership I feel even more eager to pursue a career in the field. The opportunity to be on a tenure track position in conservation biology is, therefore, a very welcomed challenge.