Bats!

Yesterday on campus I was on my way downstairs to the lab. I walked down the hall to the elevators and there were two guys standing and pointing up by the ceiling in the corner. To my surprise two bats were hanging there in their usual upside down pose. I had not even a second to think "How in the world did bats get inside this building?" before another one buzzed right past my head. This third bat clearly was feeling bolder than the two hiding from the world, because it repeatedly flew up and down the entire length of the hallway, swerving around people's heads and generally flying about frantically like bats usually do. How's that for unexpected addition to an otherwise normal Thursday?