See How Much the Cast of ‘Sesame Street’ Has Changed Since Their First Season

Though his teeth were removed by the time he appeared on Sesame Street, a more ferocious-looking Cookie Monster filmed a commercial a few years prior.

Sonia Manzano joined the cast as a 21-year-old in 1971. She's played Maria ever since, announcing her retirement in 2015.

Surprise! Oscar the Grouch wasn't always a green monster. Though he's lived in a garbage can since the show's debut in 1969, he used to be orange-y in color.

Eventually playing Maria's husband, Luis, Emilio Delgado became a series regular in 1971. He left the show in 2016.

When Big Bird made his debut in the very first episode in 1969, his head was as pointy as his beak! Even his feathers have changed.

Playing teacher Bob Johnson, Bob McGrath is one of only three performers who have been with the show since day one. He left the show in 2016.

During season 1 of Sesame Street, Grover was forest green, like "Gleep," as his original character was known on Ed Sullivan. Season 2 brought the blue Grover we know and love.

Roscoe Orman, who left the show in 2016, wasn't the original Gordon Robinson. Both Matt Robinson and Hal Miller preceded him in the friendly father role.

Frightening! Big Bird's pal Mr. Snuffleupagus used to have yellow eyes and eyelashes. Snuffy 2.0 is much more huggable.

Besides Bob McGrath, Susan Robinson is the only other human character who's still played by the original performer--in this case, Loretta Long.

Telly was initially addicted to TV (hence the name), so he had antennae on his head, plus eyes with an entranced swirl pattern.

Roscoe Orman's real-life son Miles played Gordon's adopted son, Miles Robinson, on Sesame Street. Now in his 30s, he's no longer acting. via Facebook

Maria and Luis welcomed Gabi, a girl, on Sesame Street in 1989. That newborn was actually 3-month-old Bryan Maitland, the SON of Dick Maitland in the show's sound department. Later, Sonia Manzano's real-life daughter, Gabriela Rose Reagan, played Maria's TV daughter. She left the show as a kid because "she hated being told what to do." Now both in their 20s, neither pursed performing. via <a href="https://www.facebook.com/photo.php?fbid=10153000676722751&set=pb.500372750.-2207520000.1452187242.&type=3&theater" target="blank">Bryan Maitland's Facebook page; via Gabriela Rose Reagan's Facebook page._

Source: Muppet.Wikia.com

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