Scanning electron microscopy: a potential forensic tool to identify a piece of rhinoceros horn
Keywords:Rhinoceros horn, Scanning electron microscopy, Forensic
Background: Illegal trade of rhinoceros horn in the global market has posed a serious threat to the long-term survival and the conservation of endangered one horn rhinoceros. Presence of fake horns imitating rhinoceros horn makes the situation graver. Thus, to curb the trade it is very important to scientifically identify the horns used in trade to support and strengthen the enforcement agencies. The presence of fake items makes the identification task much more difficult thus, a project entitled “Characterization of species from bone, tusk, rhino horn and antler to deal wildlife offence cases” was developed to identify rhinoceros (Rhinoceros unicornis) horn in complete to pulverized form.
Methods: Various bio-scientific techniques like morphological, analytical and molecular were applied to identify the rhinoceros horn. Most of these techniques are promising in identifying rhinoceros horn in different forms. In present paper, we discuss on identification of a piece of rhinoceros horn using Scanning Electron Microscope and total nine horns were examined. The required micrographs were saved using software Digital Image Scanning System (DISS 5, Point Electronics, Germany). Scanned images for both rhinoceros horn from wild and zoo were similar. To find the specific signature, the micrographs of the rhinoceros horn were compared with buffalo and fake horns.
Results: Differences were noted on both dorsal and ventral surfaces of rhinoceros horns examined under scanning electron microscope. On ventral surface numerous uniformly placed circular pores with mean diameter of 320 µm and had characteristic “sub pores within a pore”. Instead, in fake horn only few non-uniform pores were visible without any sub pores. The ventral portion of buffalo horn does not indicate presence of any such pores.
Conclusions: The characteristic “sub pores within a pore” signature of the ventral portion of rhinoceros horn has high potential for forensic identification and consequently, proving offences and convicting offenders.
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