Teses em Zoologia (Doutorado) - PPGZOOL/ICB
URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/3419
O Doutorado Acadêmico foi criado em 1999 e pertence ao Programa de Pós-Graduação em Zoologia (PPGZOOL) do Instituto de Ciências Biológicas (ICB) foi consolidado como um convênio entre Universidade Federal do Pará (UFPA) e Museu Paraense Emílio Goeldi (MPEG).
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Item Acesso aberto (Open Access) Estudos cromossômicos em anuros das famílias Hylidae rafinesque, 1815 e Leptodactylidae werner, 1896 (Amphibia: Anura)(Universidade Federal do Pará, 2010) SUAREZ, Pablo; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351Although there exists a large variety of chromosomal complements in Leptodactylidae (2n = 18 to 2n = 26) and Hylidae (2n = 20 to 2n = 32), the high fragmentation of data limits the access to the information about the origins and underlying mechanisms of its diversity. This, probably, had influence on the use of cytogenetic data on the characterization of species status more than been widely included in phylogenetic analyses. This work approaches, through cytogenetic data, some evolutionary aspects of three maior groups of anurans widely distributed in the Neotropical region. The genus Leptodactylus is clustered with Hydrolaetare, Paratelmatobius and Scythrophrys in the family Leptodactylidae. The chromosomal background in the genus indicates variation of the diploid numbers from 2n = 18 to 2n = 26, as well as, variation on the fundamental numbers (number of autosomic arms, FN) and on the position of Nucleolus Organizer Regions (NOR). Results of the analysis of 26 species of Leptodactylus, using several techniques, probably represents the most inclusive cytogenetic analyses on the genus Leptodactylus until now and its results provides appropriate bases to establish consistent relationships of chromosomal evolution on the genus Leptodactylus. Actually the Lophyiohylini tribe cluster 81 species distributed in 10 genera. The cytogenetic information is scarce and restrict to only 12 species. In the present study, are presented, comparatively, cytogenetic data of species from Argenteohyla, Itapotihyla, Phyllodytes, Trachycephalus and Osteocephalus genera. With exception of O. buckleyi (2n = 26; NF = 50) and P. edelmoi (2n = 22; NF = 44), the results indicate that all the others analyzed species coincide with cytogenetic data available, that indicates 2n = 24 (NF = 48) on the majority of karyotyped species, with NOR and secondary constrictions (SC) located on the 11 pair. However, in Phyllodytes edelmoi and Argentohyla siemersi pederseni, these regions are located on pairs 2 and 5, respectively. Heterochromatic blocks were associated to additional SC (fragile sites) in Osteocephalus, but not in Trachycephalus. Cytogenetic data on the Nyctimantis and Tepuihyla genera, techniques with techniques with higher resolution and more inclusive studies are necessary to better comprehend the chromosomal evolution of the tribe. The Dendropsophini tribe actually clusters the Scinax, Pseudis, Scarthyla, Sphaenorhynchus, Xenohyla and Dendropsophus genera. The registered cytogenetic data of all the genera revealed high karyotype diversity with great variation on the diploid numbers (2n = 22 in Scarthyla; 2n = 24 in Scinax and Xenohyla; 2n = 24, 24 +1- 2B e 26 in Sphaenorhynchus; 2n = 24 and 28 in Pseudis; and, 2n = 30 in Dendropsophus). The 2n=24 observed in X. truncata indicates that 2n=30 constitute a synapomorphy of the Dendropsophus genus. The NOR localization on the pair 7 is a characteristic shared by species of Scarthyla, Xenohyla, Pseudis and Sphenorhynchus, with some exceptions in the last two genera (P. caraya and S. carneus). However, the Dendropsophus genus displays an interesting diversity related to the number and its localization. On the other hand, the heterochromatin distribution presented standard variables, particularly on genus Pseudis. Although there is an exceptional chromosome variation in this group, fragmentary information in some genera made difficult to formulate consistent hypotheses about the role of chromosomes in the evolution of the group.Item Acesso aberto (Open Access) Turnover de anuros da Amazônia, perspectivas em multi escalas e habitats(Universidade Federal do Pará, 2015-03-31) BITAR, Youszef Oliveira da Cunha; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029; COSTA, Maria Cristina dos Santos; http://lattes.cnpq.br/1580962389416378Understanding the processes involved in the species spatial distribution and the reasons leading to compositional dissimilarities among sites (turnover) have been studied on different scales and habitats. In the present study, we investigated the factors affecting frogs turnover from three different perspectives. In our first chapter of this thesis, entitled "Anuran beta diversity in the mosaic anthropogenic landscape in transitional Amazon", we tested how five environments, classified according to their human pressure, can structure frogs turnover. Sampling units (SU) on this first chapter are located in a ecotone between the Amazon and Cerrado biomes, also known as "Arc of deforestation". We observed that the conversion of forested areas (riparian forests) in open environments (monoculture of grains and rubber tree) result substitution of the original species and low turnover rates, something we can call faunal homogenization. However, the concept that turnover may change over structurally different environments is not new, specially if they have a strong degradation gradient, as found in the study area. Thus, in the second chapter of this thesis, "Species turnover in Amazonian frogs: Low predictability and large differences among terra firme forests", we seek to identify how environmental and spatial variation contribute to structure communities in well preserved terra-firme forests in Amazonia. The SU for this second chapter are located over three conservation units (National Forests of Amapá, Caxiuanã and Tapajós). We observed that, despite considered within the same class (terra firme), each community responds to a singular set of environmental variables. Testing the factors influencing species turnover over different scales, we observed that both the portion explained by environment and space had greater explanatory power (r2) in regional scales when compared within each of the areas (local scale). Another interesting result was that the spatial component showed no significant influence on Caxiuanã community, where only 3% of turnover was accounted for by any of the measured environmental factors. Finally, on third chapter titled "How differences in anuran reproductive modes can affect their turnover: Comparing scales and habitats", we discusses how frogs with different reproductive modes respond to environmental and spatial variations, comparing these processes in terra firme and varzea forests. Additionally, we evaluated species probability of occurrence along measured environmental gradients. The SU in this chapter are located in three areas of terra firme 12 forest (the same as in Chapter 2) and two areas of varzea (Sustainable Development Reserve Mamirauá and Amana). Species with aquatic oviposition were prevalent in varzea, while there was a higher proportion species laying on the vegetation in Caxiuanã and more species with terrestrial reproduction in Amapá and Tapajós when compared to the other areas. By dividing the species according to their reproductive modes, clearer response patterns were observed. Also, we can assert that changes in environmental characteristics appear as major turnover driver and are important in all scales, while the spatial distance is more evident at larger scales. Thus, we can conclude that in disturbed areas faunal homogenization decreases species turnover, due to the conversion of forests into open and less heterogeneous areas. Moreover, we also observed that even in areas within the same classification and without human disturbances, there are great differences in turnover partitioning patterns, which can be assigned to a specific set spatial and environmental factors inherent to each area, in addition to species with different reproductive modes.