There is evidence of the DHARMA Initiative experimenting with animals on the Island. Specifically out of place are the polar bears. The blast door map mentions the genetic engineering of polar bears to survive tropical conditions. Another oddity that proves the DHARMA initiative is or was experimenting with animals was the shark that attacked the remains of the second raft.
Zoology was the topic of study at the Hydra station. In "", Tom makes mention of bears being locked in the cages in which Kate and Sawyer have been put. Also, Juliet refers to the room Jack was being kept in as an aquarium where dolphins and sharks were studied. There is also evidence of the DHARMA initiative using rabbits as test subjects, as seen in The Orchid video.