Radiographic analysis of Meinertzhagen's redpoll specimens: testing a purported case of fraud

Summary. Based on a detailed analysis of the external appearance of redpoll Acanthis skins, Knox (1993) explicitly accused the collector Richard Meinertzhagen of having stolen specimens from the Natural History Museum bird skin collection and re-labelling them. Here, I test Knox's results using independent evidence of the internal appearance of the specimens in question derived from radiography. Radiographic evidence strongly supported Knox's overall conclusion of fraud by Meinertzhagen but revealed limitations inherent in his attempt to determine the collection history of bird skins using external appearance alone. Although results in such investigations are inherently likely to be probabilistic rather than certain, a multi-factorial approach, taking a wide array of evidence into account, is most likely to engender confidence in the outcome.