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| Author(s): |
Priscila Fernanda Mussi Gonçalves
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) |
| Defense date: | 2009-10-21 |
| Examining board members: |
Cristina Yumi Miyaki;
Ana Maria Lima de Azeredo Espin;
Silvia Nassif Del Lama
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| Advisor: | Cristina Yumi Miyaki |
| Abstract | |
The present study was organized in five chapters. The first one is a brief review of the literature on DNA barcode, pointing out its applications and limits. The results are presented in the three subsequent chapters. The second chapter aimed to evaluate the potential of the DNA barcoding method in the distinction of 783 samples of 228 different Neotropical birds species from 16 orders, based on the difference of values of intra- and interspecific distances. DNA barcode was able to diagnose most of the species using distance values and Neighbor-joining (NJ) trees. Thus, it is a useful tool for rapid identification of Neotropical birds and it can provide information that may be relevant to biogeography studies. Some closely related species, all psitaciformes, could not be identified. Thus, the following chapter attempted to identify diagnostic characters in the DNA barcode sequences of sister species pairs of Neotropical parrots (genera Amazona, Ara, Aratinga, Brotogeris and Graydidascalus) and groups of species that could not be identified due to low interspecific distances or lack of monophyly in NJ trees (species of the genera Amazona, Aratinga, Myiopsitta, Pionites, Pyrrhura, Rhynchopsitta). The pairs of sister species had four to 39 pure diagnostic sites and closely related species had one to 11 diagnostic sites. Only the pair of species Rhynchopsitta pachyrhyncha and R. terrisi, and Amazona aestiva and A. ochrochephala did not have exclusive characters and therefore could not be identified with this method. The results showed that it is possible to identify the majority of the closely related species of this avian group using DNA barcode characters. The next chapter intended to identify the species of bird embryos apprehended from the illegal animal trade using DNA barcodes. From the total of 58 samples, 93% were identified as: three Ara ararauna, two Triclaria malachitacea and 49 Alipiopsitta xanthops. The four remaining samples (7%) were identified as Amazona aestiva and/or A. ochrochephala. These species form a complex that was already suggested in previous molecular phylogeny studies. Thus, it seems to be impossible to distinguish them based on molecular markers. DNA barcoding seems to be efficient in the identification of species of birds and is especially useful in cases where morphological data is not accessible, as the present example. Finally the main conclusions are described in the last chapter. (AU) | |