“The kangaroos were not notably reactive. No kangaroo obtained a score of greater than 6 to any objects, with the exception of the paper. The oldest male kangaroo began to devour this object and the test was discontinued after two minutes of steady chewing. The young male also chewed steadily upon the paper, although the test was completed as he made no attempts to swallow the material. Both female kangaroos showed no reaction to the paper, aside from an initial sniff in the adult subject. The youngest kangaroo (of unknown sex) grew progressively more upset as testing proceeded and we were unable to complete the last test (crumpled paper) as the animal was leaping blindly about the stall.”
Of the other species, primates were by far the most curious, whereas reptiles, as a whole, were largely indifferent – with the exception of one Orinoco crocodile “who lunged at, pushed and bit all of the test stimuli.”
A full copy of the paper may be found here.
*note: Improbable has not been able to find any online record of Richard W. Sroges, except, possibly, ‘Development of Edible Mouth Coolants’. (paperback, 1967)