Bows and arrows and complex symbolic displays 48,000 years ago in the South Asian tropics

Authors: Michelle C. Langley, Noel Amano, Oshan Wedage, Siran Deraniyagala, M.M Pathmalal, Nimal Perera, Nicole Boivin, Michael D. Petraglia, Patrick Roberts
Journal: SCIENCE ADVANCES

Archaeologists contend that it was our aptitude for symbolic, technological, and social behaviors that was central to Homo sapiens rapidly expanding across the majority of Earth’s continents during the Late Pleistocene. This expansion included movement into extreme environments and appears to have resulted in the displacement of numerous archaic human populations across the Old World. Tropical rainforests are thought to have been particularly challenging and, until recently, impenetrable by early H. sapiens. Here, we describe evidence for bow-and-arrow hunting toolkits alongside a complex symbolic repertoire from 48,000 years before present at the Sri Lankan site of Fa-Hien Lena—the earliest bow-and-arrow technology outside of Africa. As one of the oldest H. sapiens rainforest sites outside of Africa, this exceptional assemblage provides the first detailed insights into how our species met the extreme adaptive challenges that were encountered in Asia during global expansion

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Gene Flow Patterns among Aedes aegypti (Diptera: Culicidae) Populations in Sri Lanka

Authors: H.S.D. Fernando, Menaka Hapugoda, Rushika Perera, William C. Black and B.G.D.N.K. De Silva

Journal: insects

In Sri Lanka, dengue is the most serious arboviral disease. Recent increases in dengue cases suggest a higher infection rate and spread of the disease to new areas. The present study explores gene flow patterns of Ae. aegypti, the main vector of dengue disease, among 10 collection sites including major ports and inland cities using variations at 11 microsatellite loci. Discriminant analysis of principal components (DAPC) and k-means clustering estimated eight genetic clusters. Analysis of Molecular Variance (AMOVA) estimated equal variances among cities and among collections in Colombo, Sri Lanka. Significant evidence, although weak, was detected for isolation by distance. Analysis of gene flow rates and directions using MIGRATE-n indicated that populations throughout the island served as a source of immigrants for Colombo with abundant gene flow among major commercial cities in Sri Lanka, which appear to receive migrant mosquitoes from throughout Sri Lanka. The observed patterns probably arise through human movement of Ae. aegypti during commerce from throughout Sri Lanka into Colombo increasing the risk of spread. The patterns uncovered in this study are significant for global health as Sri Lanka is situated along a key international shipping route

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Water quality and microbial contamination status of groundwater in Jaffna Peninsula, Sri Lanka

Authors: M.G.Y.L. Mahagamage, Pavithrani S. Manage, Pathmalal M Manage
Journal: JOURNAL OF WATER AND LAND DEVELOPMENT

In Sri Lanka, among 2588 Salmonella positive cases, the highest incidences were recorded from Jaffna peninsula during 2005 to 2013. Therefore, the present study aimed to identify the microbiological and chemical contamination status of groundwater (40 well water) sources in Jaffna during November 2016. The total coliform, E. coli, Salmonella spp. and Shigella spp. along with some physico-chemical parameters of groundwater were studied. The results revealed that entire peninsula was contaminated with total coliform and E. coli bacteria and the parameters recorded were not within the WHO and SLS (Sri Lanka Standards) drinking water quality standards

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Systematic revision of Microhyla (Microhylidae) frogs of South Asia: a molecular, morphological, and acoustic assessment

Authors: Sonali Garg, Robin Suyesh, Abhijit Das, JiaTang Li, Nayana Wijayathilaka, A. A. Thasun Amarasinghe, Farits Alhadi, Kumar K Vineeth, N.A. Aravind, Gayani Senevirathne, Madhava Meegaskumbura, SD Biju.

Journal: Vertebrate Zoology

This study presents a systematic revision of South Asian members of the taxonomically challenging genus Microhyla Tschudi, 1838. Species relationships and diagnostic characters are determined by integrating molecular, morphological, and acoustic approaches, through which we also recognize six groups of closely related species. In addition, a new species from the southern Western Ghats of India is formally described as Microhyla darreli sp. nov. Species accounts of all the 16 recognized members from South Asia include current taxonomic status, metric and meristic characters, divergence in mitochondrial DNA, phylogenetic relationships, acoustic characters, revised geographical distributions, and natural history notes.

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