Butterstick #2!!!! (National Zoo) After the euphoria of realizing that Mei Xiang gave birth to a new baby panda yesterday, the National Zoo made this announcement late last night, complete with the above photo: “We can confirm a second cub was born at 10:07. It appears healthy.” Indeed, there some speculation that Mei Xiang could have been pregnant with twins during yesterday’s afternoon press conference, with chief veterinarian Don Neiffer saying that they wouldn’t…