Ever wonder what fleas feed on or how long they can live? Well, wonder more. Here are 10 curious facts about those pesky fleas. 1. Fleas have four life stages: egg, larva, pupa, biting adult. 2. Fleas feed on the blood of their host -- humans, birds, reptiles, and wild and domestic animals. 3. The female flea can lay 2,000 eggs in her lifetime. 4. A flea can live more than 100 days without a blood meal. 5. The female flea consumes 15 times her own body weight in blood daily.