Why did Emma Stone (whose parents named her "Emily Jean") change her name?

As she revealed to Jimmy Fallon last night, it's all thanks to Emma Bunton, aka Baby Spice of the Spice Girls.

"I wanted to be called Emma because of Baby Spice and guess what, now I am," Stone said on "The Tonight Show." "It’s pretty messed up."

"This just changed your Wikipedia page right now," Fallon joked.

The fateful name change happened when she was in second grade. "It wasn’t necessarily because of [Emma Bunton] but yes, in second grade, did I go up to the teacher and ask her on the first day to call me Emma? Yes, I did," Stone admitted.

She was shocked -- shocked -- to find out that, according to a Buzzfeed quiz (which Fallon administered) she's actually been Posh Spice this whole time.

But yes, she is going to see the Spice Girls for the umpteenth time on their upcoming reunion tour.

Stone, a natural blond who went red for her breakout film "Easy A," is blond again (like Baby Spice!) in her Netflix series, "Maniac."

She's now out promoting her Oscar contender, "The Favourite."

[Via The Wrap]