RESUMO
Large skeleton specimens are often featured as iconic open displays in Natural History Museums, for example, the blue whale 'Hope' at the Natural History Museum, London. A study on Hope's bone surface was performed to assess the biodeterioration potential of fungi. Fungi were isolated, and a fungal internal transcribed spacer (ITS) clone library survey was performed on dust and bone material. Mineral particles derived from bone and dust were analysed using energy dispersive X-ray spectroscopy, variable pressure scanning electron microscopy (SEM) and high vacuum SEM. Results showed that bone material, although mainly mineral in nature, and therefore less susceptible than organic materials to biodeterioration phenomena in the indoor environments, offers niches for specialized fungi and is affected by unusual and yet not so well-documented mechanisms of alteration. Areas of bone surface were covered with a dense biofilm mostly composed of fungal hyphae, which produced tunnelling and extensive deposition of calcium and iron-containing secondary minerals. Airborne halophilic and xerophilic fungi including taxa grouping into Ascomycota and Basidiomycota, capable of displacing salts and overcome little water availability, were found to dominate the microbiome of the bone surface.
Assuntos
Osso e Ossos/microbiologia , Fungos/fisiologia , Minerais/metabolismo , Museus , Ascomicetos/fisiologia , Basidiomycota/fisiologia , Poeira/análise , Fungos/classificação , Fungos/ultraestrutura , Hifas/fisiologia , Microscopia Eletrônica de VarreduraRESUMO
Cut-marks on fossil bones and teeth are an important source of evidence in the reconstruction of ancient butchery practices. The analysis of butchery marks has allowed archaeologists to interpret aspects of past subsistence strategies and the behavior of early humans. Recent advances in optical scanning microscopy allow detailed measurements of cut-mark morphology to be undertaken. An example of this technology is the Alicona 3D InfiniteFocus imaging microscope, which has been applied recently to the study of surface modifications on bones and teeth. Three-dimensional models generated by the Alicona microscope have been used to identify cross-sectional features of experimental cut-marks that are characteristic for specific cutting actions (e.g., slicing, chopping, scraping) and different tool types (e.g., metal versus stone tools). More recently, this technology has been applied successfully to the analysis of â¼500,000 year-old cut-marked animal bones from Boxgrove (U.K.), as well as cannibalized 14,700 cal BP year-old human bones from Gough's Cave (U.K.). This article describes molding methods used to replicate fragile prehistoric bones and teeth, where image quality was adversely affected by specimen translucency and reflectivity. Alicona images generated from molds and casts are often of better quality than those of the original specimen.