The Chinese pond mussel Sinanodonta woodiana (Lea, 1834) is a large freshwater bivalve species of the family Unionidae and a known invasive alien species. Proper verification of its identity as well ...as its source population is crucial for the control of its spread. However, its high plastic shell morphology that resembles other non-invasive species of unionids can be an obstacle. The distribution and ecological impact of this invasive unionid is not fully understood and should be further investigated to prevent further spread in the Philippines. In this study, we used the cytochrome oxidase I (cox1) gene to verify the identity of putative S. woodiana samples collected from Bato Creek in Oriental Mindoro and Lake Danao in Leyte, Philippines and elucidate their source populations. Eighteen cytochrome oxidase subunit 1 (cox1) barcodes were generated from samples collected from Lake Danao, Leyte (n=13) and Bato Creek, Oriental Mindoro (n=5). These barcodes were subjected to Basic Local Alignment Search Tool (BLAST) analysis, which showed that the cox1 sequences from the Philippine samples matched with those of S. woodiana (>94%) found in GenBank. The sequences were then aligned with cox1 sequences of S. woodiana and other unionid representatives from GenBank. Phylogenetic and haplotype network analyses also showed three haplotypes (Hap 1, 2, and 4) of S. woodiana samples from Lake Danao and Bato Creek. Hap 1 and 2 are distinct haplotypes observed in Lake Danao samples while Hap 4 is shared between Lake Danao and Bato Creek samples and have clustered with conspecific specimens from Malaysia and Indonesia, suggesting their potential Island Southeast Asian origin.
Front Cover Lutz, James A.; Furniss, Tucker J.; Johnson, Daniel J. ...
Global ecology and biogeography,
07/2018, Letnik:
27, Številka:
7
Journal Article
DNA barcoding of fishes of Laguna de Bay, Philippines Aquino, Luis Miguel G.; Tango, Jazzlyn M.; Canoy, Reynand Jay C. ...
Mitochondrial DNA,
2011-August, 8/1/2011, 2011-Aug, 2011-08-00, 20110801, Letnik:
22, Številka:
4
Journal Article
Laguna de Bay, the largest lake in the Philippines, is an important part of the country's fisheries industry. It is also home to a number of endemic fishes including Gobiopterus lacustris (Herre ...1927) of family Gobiidae, Leiopotherapon plumbeus (Kner 1864) of family Terapontidae, Zenarchopterus philippinus (Peters 1868) of family Hemiramphidae and Arius manillensis Valenciennes 1840 of family Ariidae. Over the years, a steady decline has been observed in the abundance and diversity of native fishes in the lake due to anthropogenic disturbances. In this study, a total of 71 specimens of 18 different species belonging to 18 genera, 16 families, and seven orders were DNA barcoded using the mitochondrial cytochrome c oxidase subunit I (COI) gene. All of the fish species were discriminated by their COI sequences and one endemic species G. lacustris, showing deep genetic divergence, was highlighted for further taxonomic investigation. Average Kimura 2-parameter genetic distances within species, family, and order were 1.33%, 18.91%, and 24.22%, respectively. These values show that COI divergence increases as taxa become less exclusive. All of the COI sequences obtained were grouped together according to their species designation in the Neighbor-joining tree that was constructed. This study demonstrated that DNA barcoding has great potential as a tool for fast and accurate species identification and also for highlighting species that warrant further taxonomic investigation.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Sardinella tawilis (Herre, 1927), the only freshwater sardine in the world, is endemic to Taal Lake, Philippines. It is a major fishery resource in the area. In this study, DNA barcoding using ...cytochrone c oxidase subunit (COI) gene was performed on Sardinella tawilis and its marine relatives S. fimbriata, S. jussieu, S. lemuru and Nematalosa nasus. Additional sequences from S. albella, S. atricauda, S. gibbosa, S. jussieu, S. lemuru, S. longiceps and S. melanura were obtained from GenBank. A total of 54 sequences were analyzed. The Kimura 2-parameter (K2P) distance model was used to compute the divergences of sequences within and between species and to generate a Neighbour-joining (NJ) tree. The mean in transpacific genetic distance was 0.3%, whereas the mean interspecific genetic distance was 15.2%. The genetic distance of S. tawilis from other Sardinella species ranged from 16.4% to 19.3%. S. tawilis also formed a distinct cluster in the NJ tree that is well-separated from the other species. These findings contrast with the suggestion in previous studies that S. tawilis and S. albella are ecomorphs of the same species and are not truly differentiated species based on mitochondrial control region sequence and multivariate analysis of morphological characters. This study is the first to report the occurrence of S. jussieu in the Philippines. Out of the five S. jussieu COI sequences generated in this study, two clustered with S. fimbriata, while the other three clustered with S. jussieu sequences from GenBank. Although S. fimbriata and S. jussieu are morphologically distinct based on gill raker counts, the clustering of two specimens of S. jussieu with S. fimbriata could be due to introgressive hybridization. COI sequences of S. atricauda and S. melanura from GenBank are identical. Interspecific genetic distances between some pairs of marine Sardinella are very low (0-1.6%). Further taxonomic studies using other mitochondrial and nuclear regions should be done to differentiate one species from the other and to establish their evolution relationships.
The Philippine Eagle Pithecophaga jefferyi is a diurnal raptor endemic to the Philippines. Its distribution is restricted to remaining forests on the islands of Luzon, Samar, Leyte and Mindanao. The ...Philippine Eagle is classified as a Critically Endangered species under the IUCN Red List, with a high end estimated population of only 500 breeding pairs in the wild. Population decline has been attributed to continuing deforestation, particularly since the mid-1900s, and hunting. This study aimed to identify the effects of population decline on the genetic structure of the present population of the Philippine Eagle by sequencing 1132bp of the mitochondrial control region from 22 individuals. Control region haplotype diversity (h = 0.8960±0.05590) and nucleotide diversity (π = 0.006194±0.003372) are comparable with other accipitrid species. Maximum likelihood trees and network analysis show that the Luzon and Samar individuals come from different lineages, but both shared a common ancestral population with the Mindanao population. The genetic diversity, multimodal mismatch distribution for the control region and high frequency of lower class modes all indicate a recent bottleneck for the Philippine Eagle population. Possible strategies for conservation are discussed.
An inventory of the terrestrial vertebrate species of wildlife on the campuses of the University of the Philippines (UP) Diliman and the Ateneo de Manila University in Quezon City, Metro Manila, was ...conducted between October 1997 through August 1998. The land area of the UP Diliman campus is 493 hectares while that of the Ateneo de Manila University campus is 83 hectares.A total of 76 vertebrate species was recorded in the campuses of UP Diliman and Ateneo de Manila University. This diverse assemblage of wildlife in the study sites consists of 6 species of amphibians (1 endemic), 13 species of reptiles (2 endemic), 47 species of birds (7 endemic) and 10 species of mammals (I endemic).More than 61 % of wildlife species found in the study areas were birds. Historical records of the assemblage of bird species in the UP Diliman area and its environs indicate that six species of birds used to be found in the study sites, are now no longer present.
"Collider bias" (also referred to as the "reversal paradox")1 describes the artificial association created between two exposures (A and B) when a shared outcome (X) is included in the model as a ...covariate (Figure 1). A recent paper by Aschard et al. described the potential for collider bias when adjusting for heritable covariates in genetic association studies.2 However, in their examples, the authors acknowledged that they could not exclude the possibility of a true biological explanation for the genetic association seen only in the adjusted model.
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