PubMed · 11396331
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G Musser. 2001. Galactic archaeology.. https://doi.org/10.1038/scientificamerican0601-21
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Since it has been reported that microorganisms can affect painting pigments, Paleolithic painting microbiology deserves attention. The present study is the first report on the bacterial colonization of the valuable Paleolithic paintings in the famous Altamira cave (Spain). One sample taken from a painting area in the Polychromes Hall was analyzed culture-independently. This was the first time microbiologists were allowed to take sample material directly from Altamira paintings. Identification methods included PCR amplification of 16S rRNA genes (16S rDNA) and community fingerprinting by denaturing gradient gel electrophoresis (DGGE). The applied approach gave insight into a great bacterial taxonomic diversity, and allowed the detection of unexpected and unknown bacteria with potential effects on the conservation of the painting. Regarding the number of 29 visible DGGE bands in the community fingerprint, the numbers of analyzed clones described about 72% of the phylogenetic diversity present in the sample. Thirty-eight percent of the sequences analyzed were phylogenetically most closely related to cultivated bacteria, while the majority (62%) were most closely related to environmental 16S rDNA clones. Bacteria identified in Altamira were related with sequence similarities between 84.8 and 99.4% to members of the cosmopolitan Proteobacteria (52.3%), to members of the Acidobacterium division (23.8%), Cytophaga/Flexibacter/Bacteroides phylum (9.5%), green non-sulfur bacteria (4.8%), Planctomycetales (4.8%) and Actinobacteria (4.8%). The high number of clones most closely related to environmental 16S rDNA clones showed the broad spectrum of unknown and yet to be cultivated bacteria in Altamira cave.
Phenotypic similarities between Australian Aboriginal People and some tribes of India were noted by T.H. Huxley during the voyage of the Rattlesnake (1846-1850). Anthropometric studies by Birdsell led to his suggestion that a migratory wave into Australia included populations with affinities to tribal Indians. Genetic evidence for an Indian contribution to the Australian gene pool is contradictory; most studies of autosomal markers have not supported this hypothesis (; and references therein). On the other hand, affinities between Australian Aboriginal People and southern Indians were suggested based on maternally inherited mitochondrial DNA. Here, we show additional DNA evidence in support of Huxley's hypothesis of an Indian-Australian connection using single-nucleotide polymorphisms (SNPs) and short tandem repeats (STRs) on the nonrecombining portion of the Y chromosome (NRY). Phylogenetic analyses of STR variation associated with a major Australian SNP lineage indicated tight clustering with southern Indian/Sri Lankan Y chromosomes. Estimates of the divergence time for these Indian and Australian chromosomes overlap with important changes in the archaeological and linguistic records in Australia. These results provide strong evidence for an influx of Y chromosomes from the Indian subcontinent to Australia that may have occurred during the Holocene.
Cladistics is widely used in biology and paleobiology to construct phylogenetic hypotheses, but rarely has it been applied outside those disciplines. There is, however, no reason to suppose that cladistics is not applicable to anything that evolves by cladogenesis and produces a nested hierarchy of taxa. This includes cultural phenomena such as languages and tools recovered from archaeological contexts. Two methodological issues assume primacy in attempts to extend cladistics to archaeological materials: the construction of analytical taxa and the selection of appropriate outgroups. In biology the species is the primary taxonomic unit used, irrespective of the debates that have arisen in phylogenetic theory over the nature of species. Also in biology the phylogenetic history of a group of taxa usually is well enough known that an appropriate taxon can be selected as an outgroup. No analytical unit parallel to the species exists in archaeology, and thus taxa have to be constructed specifically for phylogenetic analysis. One method of constructing taxa is paradigmatic classification, which defines classes (taxa) on the basis of co-occurring, unweighted character states. Once classes have been created, a form of occurrence seriation-an archaeological method based on the theory of cultural transmission and heritability-offers an objective basis for selecting an outgroup.