when you always take pictures of your herps, and bring them to work to show people, even when they don't want to see them!!
when you are talking to friends and family as say things like "oh and yesterday Cleo did the CUTEST thing"
When your record log book is neater and more comprehensive than you homework!
If toast always lands butter-side down, and cats always land on their feet, what happens if you strap toast on the back of a cat and drop it?"