Loss of photoluminescence in wet-preserved rat and bandicoot specimens

Abstract

Museum specimens have been used as a convenient alternative to live or fresh animals in an increasing number of studies on fur photoluminescence. Although effects of chemical preservation on specimens have been noted, they have not been experimentally tested. I used a series of experiments to answer whether fixation and wet preservation, or tanning, alters the expression of fur photoluminescence in museum specimens. The photoluminescence of northern brown bandicoot, Isoodon macrourus, fur survived initial fixation, but the photoluminescence of both bandicoot and laboratory rat, Rattus norvegicus, fur was severely compromised by longer-term preservation in ethanol. Both chemical and alum tanning eliminated the blue-white photoluminescence of rat fur, but not the pink photoluminescence of bandicoot fur. The results of these small-scale tests indicate that museum-based studies using wet-preserved specimens are likely to be an underestimate of natural photoluminescence in live animals.