Ancient DNA (aDNA) analysis of extinct ratite species is of considerable interest as it provides important insights into their origin, evolution, paleogeographical distribution and vicariant speciation in congruence with continental drift theory. In this study, DNA hotspots were detected in fossilized eggshell fragments of ratites (dated ≥25000 years B.P. by radiocarbon dating) using confocal laser scanning microscopy (CLSM). DNA was isolated from five eggshell fragments and a 43 base pair (bp) sequence of a 16S rRNA mitochondrial-conserved region was successfully amplified and sequenced from one of the samples. Phylogenetic analysis of the DNA sequence revealed a 92% identity of the fossil eggshells to Struthio camelus and their position basal to other palaeognaths, consistent with the vicariant speciation model. Our study provides the first molecular evidence for the presence of ostriches in India, complementing the continental drift theory of biogeographical movement of ostriches in India, and opening up a new window into the evolutionary history of ratites.
Summary1. Sex-linked type of defective colour vision among 608 unrelated students, including 251 males and 357 females belonging to different communities residing in Madhya Pradesh of India, was investigated. Males were found to have 3.19% defective colour vision; again, of the defectives the deutans were found to be exactly three times greater than the protans. Significantly, none of the females was colourblind.2. Brahmin of Madhya Pradesh displayed a comparatively low value of abnormal incidence being 2.88% among the other Brahmin samples. The occurrence of green-blind was found to be a little more than double of the red-blind in the sample, χ2 test for significance in respect of the total incidence of colour-blindness in various samples of Brahmin shows no heterogeneity (P>0.05). But, when certain Brahmin samples having a common origin are combined, some significant differences are brought out showing a clear statistical heterogeneity (P<0.02).
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