Document Type


Date of Award



College of Science, Engineering, and Technology (COSET)

Degree Name

MS in Biology

First Advisor

Hector Miranda


This study was conducted to test the utility of mitochondrial genes, specifically cytochrome-b, to show phylogenetic and evolutionary relationships among Southeast Asian hornbills. An interesting fact about mitochondria is that it composed of 37 genes of which 22 are tRNA, 2 rRNA, and 13 structural genes. Furthermore I have studied the phylogenetics of cytochrome-b in order to retrieve a confident evolutionary conclusion. My goal was to test the hypothesis suggesting that multiple invasion of the Philippine islands by the ancestral hornbills from mainland Asia, or the Sunda Shelf. The alternative hypothesis is that the diversity of hornbills within the Philippines was initiated by a single colonization event, followed by diversification. DNA isolation, followed by the application of the polymerase chain reaction was conducted. In addition, I ran a gel electrophoresis assay to separate on basis of size. Moreover, I underwent sequence alignment and phylogenetic analysis using maximum parsimony, distance method and maximum likelihood supported the hypothesis that the Philippine islands were colonized at least two times independently from mainland Sunda Shelf island of Borneo in the geological past; by Aceros and Buceros. One surprising result of this study is the revelation that the genus Penelopides might have evolved and diversified de novo within the Philippines.