Research

Thematic Project2015-Current: Post-doc abroad
Unveiling the hidden limits of species clusters: a cross-methodological approach to identify bioregions of Neotropical snakes

 

The identification of natural biogeographical regions is fundamental for comparisons in broad-scale ecological and evolutionary studies, and constitutes an essential tool for conservation planning. Several recent ecological and biogeographical studies have attempted to delimit bioregions at both global and local scales, and there is a long history of regionalization schemes proposed for the Neotropical region throughout the last 150 years. However, despite recent advances and proposals, there is no consensus on what kind of data are most adequate, what are the best methods for delimitating and mapping bioregions cartographically, nor which terminological system should be used for referring to the areas identified. This lack of consensus, as well as its insufficient analytical development, is surprising given that these natural units form the basis for the study of evolutionary, ecological, and geological process that spatially structure biotas. Thus, the aim of this study is to test methods and proposals of regionalization in Neotropics using real and reliable data on the geographical distribution of snakes as a model, and to compare the results with previously published proposals for other animals, plants, and abiotic features. We aim to answer the following questions: i) How do different bioregionalisation methods perform on the distributional data of Neotropical snakes? ii) How congruent are commonly recognized “Brazilian biomes” with bioregions delimited by distributional data of snakes? iii) What are the main limitations of currently available methods used in regionalization analyses for biogeography? 

Funding: University of Gothenburg and FAPESP

 

 

 

Thematic Project2015-Current: Biota Rio
Herpetofauna of the Atlantic Forest in Nova Friburgo region, state of Rio de Janeiro, Brazil (Coordinador: Msc. Breno Hamdan)

 

The aim of this project is to improve the knowledge about the biodiversity within the center of diversity and endemism of the highlands of the state of Rio de Janeiro, in the basin of Macacu river sub-basin of the river Guapiaçu. We will characterize the herpetofauna in a remnant of Atlantic forest, in the region of Nova Friburgo, state of Rio de Janeiro, contributing to the knowledge about biological diversity in the Atlantic Forest Domain. We intend to inventory and characterize the biota, and also to collect tissue samples to be used in molecular studies. We expected to increase knowledge about the diversity of the biota in the Atlantic Forest and after publish our results to scientific community and society. It will be organized a photographic catalog of these animals to be performed in the Vital Brazil Institute website (http://www.vitalbrazil.rj.gov.br). Additionally, we intend to use the data of richness and composition of herpetofauna plus environmental studies, to indicate the study area as priority for conservation.  

Funding: Vital Brazil Institute and SOS Pro-Mata Atlântica

 



 

Thematic Project2012-Current: Thematic project
Origin and evolution of snakes and their diversification in Neotropical region: A multidisciplinary approach
(Coordinator: Dr. Hussam Zaher)

Subproject: Biogeography and phylogeography of Neotropical snakes (Principal Investigator: Dr. Ricardo Jannini Sawaya)

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Funding: Museu de Zoologia da Universidade de São Paulo and FAPESP

 

     

 

Postdoctoral2012-Current: Postdoctoral researcher
Historical biogeography of snakes in the South American dry diagonal

The organisms show individual geographic distribution patterns that do not result by chance. Several past and current events are responsible for the presence of sets of taxa in a given area. The accumulation of events over time makes the reconstruction of the history of the spatial distribution of the biota a complex activity that can be explored in the light of historical biogeography. This approach looks for the correspondence between the phylogenetic relationships of taxa, their geographic distribution, and the Earth’s history. In South America, the dry diagonal form a wide band that stretches from northeastern Brazil to northwestern Argentina including at least Caatinga, Cerrado, and Chaco. Despite some similarities already detected between these sub-units of the dry diagonal, there is no consensus about its relations, stressing the importance of the historical biogeography studies in these areas. Thus, this project proposes the analysis of the historical relations between the sub-units of the dry diagonal in South America through geographical data and information on the phylogenetic relationships of snakes. We propose the following specific issues: 1) Do the Caatinga, Cerrado, and Chaco make a biogeographical unit?; 2) What are the historical relationships between these three sub-units in South America?; 3) What are the possible geological events and/or modifications of the landscape related to the historical connections found between these areas? From these questions, we will test the following hypothesis: common vicariant events between each of the three open areas of South America, Caatinga, Cerrado, and Chaco, and other forested areas, make the dry diagonal a composed area, i.e., we expect the Caatinga, Cerrado, and Chaco will not form a natural biogeographical unit. Studies that addressed the historical biogeography of the open areas of South America represent a key step towards understanding the evolutionary history of Neotropical biota.

Funding: Universidade Federal de São Paulo, Museu de Zoologia da Universidade de São Paulo and FAPESP

 


  

Snakes of the caatinga2008-2012: Doctorate degree
Snakes of the Caatinga: Diversity, natural history, biogeography, and conservation

Studies on taxonomy, richness, and geographic distribution are imperative in the Caatinga, the third most degraded Brazilian natural region and the most neglected in conservation, with a small portion of legally protected areas. Moreover, the Caatinga is one of least studied natural Brazilian regions, and this lack of data hinders the implementation of conservational measures. The scarcity of data for the Caatinga also hinders a more comprehensive knowledge in biodiversity and biogeography of the Neotropics. Herein, we provide an extensive study about richness, natural history, geographic distribution, and biogeography of the Caatinga snake fauna. This is the first study focusing on the more comprehensive Caatinga region, based on information collected from the direct analysis of 7,102 specimens housed in 17 collections of natural history, plus 250 records obtained from literature. The Caatinga harbors 112 snake species (nine families), of which 22 species (20%) are endemics. Detailed maps are provided for all species that occur in the Caatinga. The richness values double the known values for the area, and the snake endemic list is the first provided in the region. Our data shows that the Caatinga snake fauna is complex, sharing species with other Brazilian natural regions, but also harboring a unique biota of regionalized endemics. The richest areas, which host the most endemic species, are highlands (altitudes upper to 500m), and the São Francisco Dunes. Generally, the Caatinga snake species predominantly use the ground as substrate, they prey on vertebrates, and they are diurnal. The Caatinga snake fauna is not homogeneous, with major distribution patterns corroborating central predictions of the vicariance model. The snakes showed significantly clustered ranges, forming eight biotic elements inside the Caatinga. Distribution patterns corroborate major topographical, pedological, and vegetational divisions known to the Caatinga. Based on diversity data, geographic distribution, and biogeography provided here, the conservation of the snakes and the Caatinga is discussed.

Funding: Universidade Estadual Paulista “Júlio de Mesquita Filho, Instituto Butantan, FAPESP and INCTTox

 

 

Master's degree2004-2006: Master’s degree
Community structure of snakes from the Caatinga area in Northeast Brazil

The aim of this work is to describe the composition, diversity of species, and regulating factors of the community structure of the snakes from Seridó Ecological Station (Caatinga, Serra Negra do Norte county, State of Rio Grande do Norte, Brazil). The community was composed by 13 species (2 Boidae, 1 Viperidae, 1 Elapidae, and 9 Colubridae) with a diversity index of 1.98; the meeting rate was independent from climactic factors. Six of the collected species were terrestrial, three were arboreal, three were terrestrial-arboreal, and one was terrestrial-fossorial; four species were diurnal, five were nocturnal, and four were diurnal/nocturnal. The use of space and time was analyzed for those species from which five or more specimens were collected: Philodryas nattereri, Oxybelis aeneus, Leptodeira annulata, Boa constrictor, Erythrolamprus dilepis, and Micrurus aff. ibiboboca. A high degree of overlapping in the use of space by pairs of species was verified. Food was a scarce factor. Differences in the activity period may constitute the niche axis that makes coexistence of species possible. Twenty-six specimens from the two most abundant species also were dissected: 13 from Philodryas nattereri and 13 from Oxybelis aeneus. After anatomical dissection and laboratorial examination of the respiratory tract of the P. nattereri, it was found to be parasitized by two species of pentastomids: Cephalobaena tetrapoda, which had a prevalence of 30.8% and an average intensity of infection of 51.5 ± 32.7 (range 3-147), and Raillietiella furcocerca, which had a prevalence of 7.7% and an average intensity of infection of 1.0. Only one female of O. aeneus was found to be infected by C. tetrapoda, which had a prevalence of 7.7% and an average intensity of infection of 2.0. There was no significant relationship between the size of snout-vent length (SVL) and infection intensity in the specimens investigated here. The two individuals of P. nattereri, infected by more than 40 specimens of pentastomids, had their lungs completely infected by these parasites including the pulmonary peritoneum and trachea. The contrasting rates of infection estimated here may be related to foraging strategies, diet, and habitat selection performed by individuals of P. nattereri and O. aeneus. The scarcity of food can factor to high levels of infection by pentastomids and may be harmful to the community structure.

Funding: Universidade Federal do Rio Grande do Norte and CAPES

 

Snake Bite2000-2004: Monography
Study of the accidents caused by snake genus Bothrops (Viperidae) notified in the state of Paraíba, Brazil.

The ophidian accident is the group of factors related to snake bites. In the state of Paraíba, the data is scarce, which is harmful to the treatment of the poisoning victims. This work sought to trace the clinic-epidemic profile of proved accidents caused by snakes of Bothrops genus, notified in the period between January 1995 and December 2003. In the present study, 1,098 of the notifications of accidents in Paraíba were caused by Bothrops and recorded by the Regional Nucleus of Health (3° RNH), Division of Vigilance Epidemiologic (DVE) of the Municipal Secretary of Health from Campina Grande, on Assistance Center of Toxicology (ACT) from João Pessoa and Campina Grande, and the State Secretary of Health (SSH). This data allowed us to conclude that the accidents happened especially in the districts of João Pessoa (4.6%), Rio Tinto (1.5%), and Alhandra (1.2%). The accidents happened mainly in August (11.9%), July (11.7%), and March (9.7%); predominantly in rural zones (12.8%), in the diurnal period (3.5%), to males (17.9%), often rural workers (4.6%), when they were developing their work (4.4%) and with those aged between 10 and 39 (13.9%). The anatomic areas frequently attained were the inferior members (11.8%). The time between the moment of being bit and medical aid was bellow six hours in 10.4% of cases and the time between the bite and the discharge from hospital was more than 6 hours in 3.7% of the cases. The accidents by Bothrops are characterized by pain (15.3%), edema (13.8%), and erythema (3.1%) like local disturbances; alteration on coagulation (2.9%) and bleeding gums (0.9%); Myalgia and anuria in 0.8% and 0.5% of cases, respectively; palpebral ptosis in 0.2% of cases, like neurologic alterations. There was a higher frequency on moderated cases (6.6%) and 12.1% of the cases resulted in cure; 2.7% got better with sequelae (27 amputations) and 0,5% resulted in death. The high indication of ignored and/or non-notified cases suggests that it is not possible to make a clinic-epidemic coherent profile of accidents caused by Bothrops, which happened between January of 1995 and December of 2003, in Paraíba.

Funding: Universidade Estadual da Paraíba