Singer and actress appears to have slimmed down over the years

Jennifer Lopez, ButtVinnie Zuffante, Douglas Gorenstein/NBC/Getty Images

Remember when Jennifer Lopez‘s bootylicious bottom was all anyone could ever talk about?! Yeah, we do too.

But lately it seems like her famous figure isn’t quite as curvy as it once was. What gives, J.Lo?

Don’t get us wrong, the mother of two hasn’t missed a beat throughout her career and has managed to look nothing short of flawless ever since she stepped onto the scene.

In fact, it has been more than 15 years since she first shook what her mama gave her onstage (Side note: you guys, On the 6 is almost two decades old?!), so it’s only natural that her derrière may have changed a bit.

If anything, this is just an excellent excuse for us to pore over old pictures of J.Lo’s ridiculously gifted rear. So let’s get to it, shall we?

PHOTOS: Jennifer Lopez’s best looks

Jennifer LopezJeffrey Mayer/WireImage.com

Flashback to the London Maid in Manhattan red carpet premiere back in 2003…J.Lo is sporting a skintight tan gown that highlights her sexy silhouette.

It may have seemed demure compared to her scandalous Versace Grammys gown years prior, but her killer bod was definitely on display. In other words, there was no denying that Jenny from the block was working with something serious.

Jennifer LopezInstagram

Then there was her performance at Jingle Ball that year…

The American Idol judge opted to wear high-waisted pants that hugged her every enviable curve.

And let’s not forget that over the years she’s been the focus of countless photo shoots, many of them with little to no clothing involved.

Jennifer LopezGrifoni-Sarmiento/Splash News

And just five years ago, the brunette beauty was vacationing with her then-hubby Marc Anthony in a teensy red string bikini that barely provided any coverage.

Cut to last night, when the “First Love” singer made an appearance on the Late Show with Jimmy Fallon in a white cocktail dress.

She may have tried to distract us with her ample cleavage in the low-cut frock, but all we could pay attention to was her backside as she danced with the host.

So was it just the dress? Or is J.Lo’s shape changing before our very eyes? We’ll let you decide!

Jennifer Lopez, Jimmy Fallon