Geographical variation was examined morphologically in the common tree shrew (Tupaia glis) in some Indochinese and Malayan regions. Osteometrical examination and principal component analysis elucidated the morphological differences among various populations. The populations from southern and western Thailand were distinguished morphologically from the other populations. Variation in males from south Thailand and Kuala Lumpur suggests that the Isthmus of Kra may have an influence on the variation of skull morphology. However, the Isthmus of Kra was not completely considered as a factor of geographical separation in this species, because we could not confirm the separation in skull size and shape between the localities at least in females. While, the Kanchanaburi population in western Thailand was significantly smaller than the other population in skull size, and constituted the morphologically separable group in our study.
The distribution of lectin bindings in the testis of babirusa, Babyrousa babyrussa (Suidae) was studied histochemically using 10 biotinylated lectins, Peanut agglutinin (PNA), Ricinus communis agglutinin (RCA I), Dolichos biflorus agglutinin (DBA), Vicia villosa agglutinin (VVA), Soybean agglutinin (SBA), Wheat germ agglutinin (WGA), Lens culinaris agglutinin (LCA), Pisum sativum agglutinin (PSA), Concanavalin A(Con A) and Ulex europaeus agglutinin (UEA I). Nine of 10 lectins showed a variety of staining patterns in the seminiferous epithelium and interstitial cells. The acrosome of Golgi-, cap- and acrosome-phase spermatids displayed various PNA, RCA I, VVA, SBA and WGA bindings, indicating the presence of glycoconjugates with D-galactose, N-acetyl-D-galactosamine and N-acetyl-D-glucosamine sugar residues respectively. No affinity was detected in the acrosome of late spermatids. LCA, PSA and Con A which have affinity for D-mannose and D-glucose sugar residues were positive in the cytoplasm of spermatids and spermatocytes. DBA was positive only in spermatogonia. In addition to DBA, positive binding in spermatogonia was found for VVA, WGA and Con A, suggesting the distribution of glycoconjugates with N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, D-mannose and D-glucose sugar residues. Sertoli cells were stained intensely with RCA I, WGA and Con A. In Leydig cells, RCA I and Con A were strongly positive, while WGA, LCA and PSA reactions were weak to moderate. The present findings showed that the distribution pattern of lectin binding in the testis of babirusa is somewhat different from that of pig or other mammals reported previously.
This is the first publication on the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in riverine and coastal sediments in South East Asia where the rapid transfer of land-based pollutants into aquatic environments by heavy rainfall and runoff waters is of great concern. Twenty-nine Malaysian riverine and coastal sediments were analyzed for PAHs (3-7 rings) by gas chromatography mass spectrometry. Total PAHs concentrations in the sediment ranged from 4 to 924 ng/g. Alkylated homologues were abundant for all sediment samples. The ratio of the sum of methylphenanthrenes to phenanthrene (MP/P), an index of petrogenic PAHs contribution, was more than unity for 26 sediment samples and more than 3 for seven samples for urban rivers covering a broad range of locations. The MP/P ratio showed a strong correlation with the total PAHs concentrations, with an r2 value of 0.74. This ratio and all other compositional features indicated that Malaysian urban sediments are heavily impacted by petrogenic PAHs. This finding is in contrast to other studies reported in many industrialized countries where PAHs are mostly of pyrogenic origin. The MP/P ratio was also significantly correlated with higher molecular weight PAHs such as benzo[a]pyrene, suggesting unique PAHs source in Malaysia which contains both petrogenic PAHs and pyrogenic PAHs. PAHs and hopanes fingerprints indicated that used crankcase oil is one of the major contributors of the sedimentary PAHs. Two major routes of inputs to aquatic environments have been identified: (1) spillage and dumping of waste crankcase oil and (2) leakage of crankcase oils from vehicles onto road surfaces, with the subsequent washout by street runoff. N-Cyclohexyl-2-benzothiazolamine (NCBA), a molecular marker of street dust, was detected in the polluted sediments. NCBA and other biomarker profiles confirmed our hypothesis of the input from street dust contained the leaked crankcase oil. The fingerprints excluded crude oil, fresh lubricating oil, asphalt, and tire-particles as major contributors.
The geographical variation of the gray-bellied squirrel (Callosciurus caniceps) was examined using osteometry of skull in Southeast Asia. From the principal component analysis (PCA), the plots of the northern localities from Nan to Kanchanaburi and those of the southern localities from Narathiwat to Kuala Lumpur in male were completely separated. In female, the plots of the locality from Uttradit to Kanchanaburi and those of the locality from Pattani to Negri Sembilan were completely separated. We called these northern localities and southern localities which are distinguished by the PCA as N group and S group. The size and shape of the skulls of these squirrels indicated the differences between N group and S group from t-test and U-test. These results may be influenced by the two transitions of the phytogeography around the southernmost locality in N group and the northernmost locality in S group in the peninsular Thailand and Malay Peninsula. Localities which are located between N and S groups were called the Middle (M) group. From the PCA among N, S groups and each locality of M group, the plots of localities such as Prachuap Khiri Khan, Chumphon, Krabi, Nakhon Si Thammarat and Trang in both sexes of M group could not be separated from those of N and S groups. We suggest that the sympatric distribution of N and S groups and the hybrid of N and S populations may be seen in these localities of M group.