When the Beastie Boys rose to fame with the release of “Licensed to Ill,” it would have been inconceivable that three bratty rappers who spit rhymes about beer and women would grow into ambassadors of peace and love. The catalyst was Adam Yauch, better known as MCA, who died Friday, May 4, after a three-year fight with cancer.

The Beastie Boys evolved musically and spiritually over the years. The group’s early sound featured classic rock riffs and was credited for winning over an audience that had been slow to embrace rap. Its debut album was the first rap album to reach No. 1 on the Billboard chart in 1986, due to the crossover appeal of the hit single, “(You Gotta) Fight for Your Right (to Party)” and its video parodying drunken frat-boy behavior.

According to Yauch, the song was “a joke that went too far … the strangest part about it was that after a short time I think we actually became just what it was that we’d set out to make fun of.”

The Beastie Boys rejected the sound and image associated with its first record, re-emerging with “Paul’s Boutique.” The album was not a hit but became a critical favorite, helping popularize the process of sampling; Rolling Stone commented that it “ambitiously stitches together song fragments in a way rarely seen before or since.”

During a snowboarding trip through Nepal, Yauch discovered Buddhism, and this influence seeped into his music. Most Beastie Boys lyrics had been composed of jokes and pop culture references. These were soon supplemented with rhymes about respect and spiritual awakening. The next two records, “Check Your Head” and “Ill Communication,” featured songs like “Namaste” and “Boddhisatva Vow,” reflecting Buddhist beliefs. The single “Sure Shot” showed evidence of Yauch’s remarkable transformation.

While early songs featured misogynistic lyrics, he now rapped, “I want to say a little something that’s long overdue/ The disrespect to women has got to be through/To all the mothers and the sisters and the wives and friends/I want to offer my love and respect to the end.”

Continuing its evolution, the group now played instruments on many songs, with Yauch on bass. The band incorporated funk, jazz and hardcore punk into its signature sound, finding a new alternative- rock audience.

MCA began the next chapter of his life as a philanthropist and activist. He organized the Tibetan Freedom Concerts, which raised millions of dollars for the Free Tibet movement. Yauch made headlines for his statements at MTV’s 1998 Video Music Awards, condemning the bombing of Iraq and American racism toward Arabs. Last fall, though weakened by cancer treatments, Yauch was seen marching with protesters at Occupy Wall Street.

Yauch continued to make music, even after being diagnosed with a cancerous parotid gland in 2009, and the Beastie Boys was inducted into the Rock and Roll Hall of Fame last month. MCA was too sick to attend the ceremony and died just a few weeks later. But, his legacy lives on with all the fans he entertained and enlightened over the years.