An overview to the investigative approach to species testing in wildlife forensic science

Abstract

The extent of wildlife crime is unknown but it is on the increase and has observable effects with the dramatic decline in many species of flora and fauna. The growing awareness of this area of criminal activity is reflected in the increase in research papers on animal DNA testing, either for the identification of species or for the genetic linkage of a sample to a particular organism. This review focuses on the use of species testing in wildlife crime investigations. Species identification relies primarily on genetic loci within the mitochondrial genome; focusing on the cytochrome b and cytochrome oxidase 1 genes. The use of cytochrome b gained early prominence in species identification through its use in taxonomic and phylogenetic studies, while the gene sequence for cytochrome oxidase was adopted by the Barcode for Life research group. This review compares how these two loci are used in species identification with respect to wildlife crime investigations. As more forensic science laboratories undertake work in the wildlife area, it is important that the quality of work is of the highest standard and that the conclusions reached are based on scientific principles. A key issue in reporting on the identification of a particular species is a knowledge of both the intraspecies variation and the possible overlap of sequence variation from one species to that of a closely related species. Recent data showing this degree of genetic separation in mammalian species will allow greater confidence when preparing a report on an alleged event where the identification of the species is of prime importance. The aim of this review is to illustrate aspects of species testing in wildlife forensic science and to explain how a knowledge of genetic variation at the genus and species level can aid in the reporting of results.

Egg forensics: An appraisal of DNA sequencing to assist in species identification of illegally smuggled eggs

“…Ultimately, the ability to make accurate species assignments based on mtDNA sequences is underpinned by the coverage and quality of DNA reference databases, together with the accuracy of the taxonomic framework. Without a comprehensive knowledge of intra-and inter-species variation for the mtDNA loci used for species identification, regardless of percentage sequence similarity, there still may be doubt as to the accuracy of taxonomic assignments [39]. Importantly, if mtDNA sequence data are to be used in a legal context it is vital that reference sequences are fit for purpose and have passed the scrutiny of peer review.…”

Dna Barcoding as a Wildlife Forensic Tool (Wft) for Species Identification: A Case Study on Blackbuck (Antilope Cervicapra) in India.

“…The introduction of DNA barcoding highlighted the expanding use of mitochondrial COI gene as a genetic marker, considered that the barcode sequence ideal for effective species identification (Iyengar, 2014;Hebert et al, 2003;Dawnay et. al., 2007;Linacre and Tobe, 2011). In the present study, mitochondrial COI…”

A Pioneer Case Study on Identification of Infant Rhinoceros Horn

“…Morphology and microscopy are the natural starting points in identification [8]. However, the morphological examination has some limitations especially when material is present as powders, potions, oils [3], examination from old, degraded [9], partial, small parts [7] or processed, tanned, finished wildlife products [10]. Currently, DNA sequencing analysis is the proven and most reliable method used for species identification from confiscated biological samples [7].…”

“…But accurate identification of the species from confiscated biological material is of paramount importance to the investigation of crime in forensics [5], fixing the accurate wildlife offence [6] and so as to prove the conviction of crime by offenders [7]. The test employed depends on the material seized and the available techniques [3]. Morphology and microscopy are the natural starting points in identification [8].…”

“…Illegal poaching are threats to a wide range of endangered species around the world [2]. Many species are protected both at a national and international level and their conservation requires control of illegal poaching [3]. Concept of "species" is perhaps the most debated subject in evolutionary biology [4].…”