Isso pode ser Um Dia de Danação , de David Gerrold. É o segundo livro de sua série A Guerra Contra o Chtorr .
Os Chtorr são alienígenas que se parecem com vermes gigantes e realmente se enterram no chão. Em A Day for Damnation, um dos Chtorr foi capturado e está sendo experimentado para ver como ele é inteligente. Um dos testes é verificar se o Chtorr pode resolver uma série de problemas para abrir uma gaiola com um coelho. Os cientistas apelidaram o Chtorr Tiny :
"For your information," Fletcher said, "Tiny has never seen this puzzle before. It is not the most complicated one we've assembled, but for the purposes of this demonstration we thought we'd keep it short. All of our puzzles are rigged to keep a record of Tiny's moves-and once Tiny goes to work the life-expectancy of the rabbit can be measured in minutes. The longest Tiny has ever taken was half an hour."
...
That means Tiny's solved the puzzle," said Fletcher. - the glass case popped open. Tiny grabbed the rabbit with one dark claw, lifted it up high, it squealed, I didn't know that rabbits could scream-and shoved the creature into its gaping maw. There was a wet slobbery crunching sound, and then Tiny uttered a soft trill of pleasure, and looked around for more.