It’s a no brainer that Lady Gaga and Pink are not the names found on their birth certificates… but you’d be surprised how many other celebrities are going by an alias, too. Like did you know Meryl Streep or Reese Witherspoon don’t go by her birth name? How about Jodie Foster or Dakota Fanning or Brad Pitt or Tyler Perry. We could go on. Click through our slideshow to see 30 surprising celebrity name changes.