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Human migration in response to past climate change has been recorded globally. The pastoralist Todas are believed to have colonised the higher elevations (>2000 m asl) of the Nilgiris, Western Ghats, India, after ∼2000 cal. yr BP. During the late Quaternary, climate-induced vegetation shifts in tropical montane forest-grassland mosaic of the Nilgiris have been well-documented using stable carbon isotopes and pollen, but there have been no corresponding investigations of human activity. We used several proxies to infer the human ecology of this region. Radiocarbon-dated (∼22,000 cal. yr BP to the present) peat from Sandynallah (2200 m asl) was used to reconstruct fire history, animal abundance, and human presence since the Last Glacial Maximum (LGM). While macro-charcoal records fires at the LGM, macro- and micro-charcoal indicate intense fire at ∼3500 cal. yr BP, coprophilous fungal spores indicate abundant herbivorous mammals, n-alkane signatures point to arid grassland vegetation, and steroid biomarkers show human faecal remains for the first time. We infer that a pastoralist people, most likely the Todas, migrated to the montane Nilgiris along with their buffaloes in response to prolonged or abrupt climate change in peninsular India ∼3500 cal yr BP or ~1500 years prior to what historical accounts assume. [ABSTRACT FROM AUTHOR]

Abstract: The primary objective of this study was to assess the expression profile and levels of toll-like receptor (TLR) mRNAs in the spleen, lung, mediastinal lymph node (MLN), jejunum, rectum, skin and peripheral blood mononuclear cells (PBMC) of Toda and Murrah buffalos. Spleen and PBMC had increased expression of TLR mRNAs 2, 4, 5, 6, 8, 9 and 10; lung had increased expression of TLR mRNAs 2, 4, 5, 6 and 8, MLN TLR mRNA 6, 9, 10 and decrease in TLR 3 and 7 mRNAs in skin. No significant differences were observed in the expression levels of any of the TLR mRNA in jejunum and rectum. Toda buffaloes showed significantly higher expression levels of TLR 9 mRNA in MLN, TLR mRNAs 1, 5, 6, 9 and 10 in skin and TLR mRNAs 2, 4, 7 and 9 in PBMC than Murrah buffaloes living in the vicinity. Toda and Murrah buffaloes were inoculated with TLR5 (flagellin) and TLR9 (CpG ODN) ligands in vivo and expression levels of the respective TLRs analyzed 12h later. Following CpG inoculation, Toda buffaloes had significantly higher levels of TLR 9 mRNA expression but not in Murrah. However, flagellin induction did not increase TLR 5 mRNA expression in both these breeds. Histological sections of the skin were made and infiltrating cell clusters were graded and quantified. Following CpG inoculation, Toda buffaloes showed higher numbers of infiltrating grade 1 and grade 3 cell clusters while Murrah showed lower numbers of infiltrating grade 1 cells as compared to mock-inoculated skin sections. Flagellin treatment revealed no significant differences in infiltrating cell clusters in both the breeds. The results have shown differential expression of TLR mRNAs in various tissues between two divergent buffalo breeds with the highest difference in TLR expression profile seen in the skin, the largest portal of entry of pathogens, of Toda. [Copyright &y& Elsevier]