Stevenson J.,Asia Pacific College |
Siringan F.,University of the Philippines at Diliman |
Finn J.,Asia Pacific College |
Madulid D.,National Museum of the Philippines |
Heijnis H.,Australian Nuclear Science and Technology Organisation
Global Change Biology | Year: 2010
The last 7000 years of environmental history for Paoay Lake and its surrounding landscape is examined through the analysis of pollen, diatoms, charcoal, mineral magnetics and AMS dating. Basal sediments contain shells of Cerithiidae and the saline-tolerant diatom Diploneis indicating that this was an estuarine environment before becoming a freshwater lake after 6000 bp. Pollen analysis shows that submontane forests, characterized by Pinus pollen, underwent a major disturbance around 5000 years ago, recovering to previous levels by 1000 years ago. Charcoal as an indicator of fire is abundant throughout record, although the highest levels occur in the earlier part of the record, between 6500 and 5000 years ago. An aspect of the project was to examine whether there is evidence of land clearance and agricultural development in the region during the late Holocene. While a clear signal of human impact in the record remains equivocal, there appears to be a correspondence between submontane forest decline and mid-Holocene ocean data that depict warmer and possibly drier conditions for the region. The study highlights the vulnerability of these montane forests to forecasts of a warmer and drier climate in the near future. © 2009 Blackwell Publishing Ltd.
Ding H.-H.,CAS South China Botanical Garden |
Ding H.-H.,University of Chinese Academy of Sciences |
Chao Y.-S.,Kaohsiung Medical University |
Callado J.R.,National Museum of the Philippines |
Dong S.-Y.,CAS South China Botanical Garden
Molecular Phylogenetics and Evolution | Year: 2014
In this study we provide a phylogeny for the pantropical fern genus Tectaria, with emphasis on the Old World species, based on sequences of five plastid regions (atpB, ndhF plus ndhF-trnL, rbcL, rps16-matK plus matK, and trnL-F). Maximum parsimony, maximum likelihood, and Bayesian inference are used to analyze 115 individuals, representing ca. 56 species of Tectaria s.l. and 36 species of ten related genera. The results strongly support the monophyly of Tectaria in a broad sense, in which Ctenitopsis, Hemigramma, Heterogonium, Psomiocarpa, Quercifilix, Stenosemia, and Tectaridium should be submerged. Such broadly circumscribed Tectaria is supported by the arising pattern of veinlets and the base chromosome number (x= 40). Four primary clades are well resolved within Tectaria, one from the Neotropic (T. trifoliata clade) and three from the Old World (T. subtriphylla clade, Ctenitopsis clade, and T. crenata clade). Tectaria crenata clade is the largest one including six subclades. Of the genera previously recognized as tectarioid ferns, Ctenitis, Lastreopsis, and Pleocnemia, are confirmed to be members in Dryopteridaceae; while Pteridrys and Triplophyllum are supported in Tectariaceae. To infer morphological evolution, 13 commonly used characters are optimized on the resulting phylogenetic trees and in result, are all homoplastic in Tectaria. © 2014 Elsevier Inc.
Detroit F.,French Natural History Museum |
Corny J.,French Natural History Museum |
Corny J.,University of Ferrara |
Dizon E.Z.,National Museum of the Philippines |
Mijares A.S.,University of the Philippines at Diliman
Human Biology | Year: 2013
"Pygmy populations" are recognized in several places over the world, especially in Western Africa and in Southeast Asia (Philippine "negritos," for instance). Broadly defined as "small-bodied Homo sapiens" (compared with neighboring populations), their origins and the nature of the processes involved in the maintenance of their phenotype over time are highly debated. Major results have been recently obtained from population genetics on present-day negrito populations, but their evolutionary history remains largely unresolved. We present and discuss the Upper Pleistocene human remains recovered from Tabon Cave and Callao Cave in the Philippines, which are potentially highly relevant to these research questions. Human fossils have been recovered in large numbers from Tabon Cave (Palawan Island) but mainly from reworked and mixed sediments from several archaeological layers. We review and synthesize the long and meticulous collaborative work done on the archives left from the 1960s excavations and on the field. The results demonstrate the long history of human occupations in the cave, since at least ~30,000 BP. The examination of the Tabon human remains shows a large variability: large and robust for one part of the sample, and small and gracile for the other part. The latter would fit quite comfortably within the range of variation of Philippine negritos. Farther north, on Luzon Island, the human third metatarsal recently recovered from Callao Cave and dated to ~66,000 BP is now the oldest direct evidence of human presence in the Philippines. Previous data show that, compared with H. sapiens (including Philippine negritos), this bone presents a very small size and several unusual morphological characteristics. We present a new analytical approach using three-dimensional geometric morphometrics for comparing the Callao fossil to a wide array of extant Asian mammals, including nonhuman primates and H. sapiens. The results demonstrate that the shape of the Callao metatarsal is definitely closer to humans than to any other groups. The fossil clearly belongs to the genus Homo; however, it remains at the margin of the variation range of H. sapiens. Because of its great antiquity and the presence of another diminutive species of the genus Homo in the Wallace area during this time period (H. floresiensis), we discuss here in detail the affinities and potential relatedness of the Callao fossil with negritos that are found today on Luzon Island. © 2013 Wayne State University Press.
Brown R.M.,University of Kansas |
Diesmos A.C.,National Museum of the Philippines |
Oliveros C.H.,University of Kansas
Journal of Herpetology | Year: 2011
We describe a new species of Luperosaurus from the Luzon faunal region, northern Philippines. The new species is most similar to, and has long been confused with, Luperosaurus cumingii from Luzon Island but differs from this and all other Luperosaurus by numerous characters of scalation, color pattern, and a suite of variables related to its small body size. The new species has been recorded at four localities along the eastern seaboard of Luzon and on Camiguin Norte, a small island just northeast of Luzon; it may also occur on Polillo and Lubang Islands. Data from our recent survey work suggest that some Luperosaurus species may be adapted to low elevation, coastal forest and that these species may now be encountered rarely now because this habitat type is so severely imperiled by centuries of deforestation and near complete development of virtually all Philippine coastlines. © 2011 Society for the Study of Amphibians and Reptiles.
Linkem C.W.,Biodiversity Research Center |
Hesed K.M.,Biodiversity Research Center |
Hesed K.M.,University of Maryland University College |
Diesmos A.C.,National Museum of the Philippines |
Brown R.M.,Biodiversity Research Center
Molecular Phylogenetics and Evolution | Year: 2010
In the megadiverse conservation hotspot of the Philippines, biodiversity is not uniformly distributed throughout the archipelago, but hierarchically partitioned into islands and island groups that were conjoined during the mid- to late-Pleistocene. Few species groups are widely distributed throughout the archipelago, but some exceptions exist, such as the common scincid lizards of the Sphenomorphus jagori complex (including S. jagori, S. coxi, and S. abdictus). Using mtDNA haplotype data we test biogeographic and taxonomic predictions in these abundant, large-bodied, forest floor lizards and arrive at conclusions that differ significantly from both past, and current, appraisals of species diversity. In contrast to expectations based on existing taxonomy (three species, each with two subspecies), we find evidence of at least eleven highly divergent species lineages diagnosed by haplotypic variation. Each lineage corresponds to a biogeographically circumscribed distribution (i.e., isolated islands or geological components of islands), suggesting lineage cohesion and allopatric differentiation. Parametric bootstrapping tests reject taxonomic and biogeographic hypotheses and suggest a complex pattern of unpredicted relationships. Only one of the former species (S. jagori) appears as a monophyletic entity (including four allopatric, highly divergent lineages that we suspect may represent evolutionary species), and the remaining species are paraphyletic, necessitating a comprehensive future taxonomic revision. The pattern of biogeographic provincialism and hidden cryptic species diversity detected here leads us to suspect that even the most common, presumably well-studied, and widespread species complexes in the Philippines are in need of thorough analysis with modern genetic and phylogenetic techniques. Such studies of speciation genetics in these common, widely distributed groups may lead to a better understanding of the genetic underpinnings of biodiversity, allow for an enhanced appreciation of the evolutionary history of this model island archipelago, and enable more informed conservation planning in a global biodiversity hotspot. © 2010 Elsevier Inc. All rights reserved.