On their sophomore album Powerplant, Girlpool’s Cleo Tucker and Harmony Tividad age more gracefully than most acts garnering breathless praise while still in high school. While the themes of their self-titled EP and debut LP Before the World Was Big could be easily distilled into single phrases (“what it feels like for a girl” and “growing up,” respectively), *Powerplant *is something subtler. Its 12 tracks run a gamut of difficult-to-articulate emotions, all conveyed through the vividly imagistic lyrics that have always distinguished Girlpool’s songwriting. They also embrace a more complex rock sound, with the addition of drummer Miles Wintner. Originally known for singing in plaintive unison, Tucker and Tividad have become sophisticated architects of vocal texture and harmony.

This evolution situates Girlpool within a decades-old tradition of women (and those who don't ID as male) blending their voices to make rock music that passes a sort of aural Bechdel test. Although they may not seem so revolutionary now, successful bands whose lineups included more than one non-male were astoundingly rare until the punk era, nearly a quarter-century after the birth of rock. While vocal-driven girl groups dominated the pre-Beatles pop scene, the sound of multiple women playing guitars, pounding drums, and singing songs they’d written together had a different effect. Within an industry that usually prefers to set women up as rivals, these harmonies served as a resounding testament to the power of female collaboration.

As such, we’ve compiled a 16-song history of the female alt-rock vocal harmony, from the Shaggs to Sleater-Kinney to Haim. This album’s worth of touchstones and rarities is by no means comprehensive. It’s intended, instead, as a mere introduction to the radical possibilities of women’s intertwined voices.

(Editor’s note: It came to our attention after the publishing of this piece that Girlpool’s Cleo Tucker has come out as gender non-binary in recent weeks. Pronouns have been adjusted herein.)

Prototypes

The Shaggs — “Philosophy of the World” (1969)

All-female rock bands (or, really, rock bands with more than one woman in them) weren’t entirely unheard of before the ’70s, but even if they weren’t the first, the Shaggs were certainly the strangest. In the mid-’60s, inspired by a prophecy from his fortune-telling mother (really), Austin Wiggin organized his daughters Helen, Betty, Dot, and sometimes Rachel into an act that was to rock what outsider art is to the masterpieces that hang in museums. You can hear the seeds of lo-fi ’80s twee-pop on cult-classic tracks like “Philosophy of the World,” which layers the girls’ voices in messy yet effective choruses.

The Runaways — “Cherry Bomb” (1976)

The Runaways story is, in large part, a tale of five teenage girls’ exploitation and sexual abuse at the hands of their amoral svengali, Kim Fowley. But the L.A. band’s brief mid-’70s discography remains a great early example of female rock musicians playing instruments and singing together—work that launched the careers of Joan Jett and Lita Ford, who would go on to become rock icons in their own right. On the Runaways’ flagship single, when the entire band grabs a mic to scream “cherry bomb!” along with lead vocalist Cherie Currie, the effect is terrifying in the best way possible.

The Slits — “Typical Girls” (1979)

In the second half of the ’70s, British punk and post-punk brought an unprecedented number of female-fronted rock bands into the spotlight, from Siouxsie and the Banshees and X-Ray Spex to the Au Pairs and Essential Logic. All-women groups—like the classic Slits lineup of Ari Up, Viv Albertine, Tessa Pollitt, and Palmolive—were rarer, though. Their defining hit, “Typical Girls,” is a call-and-response indictment of society’s boring and oppressive standards for their gender.

The Raincoats — “Lola” (1979)

The Slits’ contemporaries, the Raincoats, had two captivating singers in guitarist Ana da Silva and bassist Gina Birch. Sometimes they alternated lead vocal duties; sometimes they sang simultaneously, backed up by other female band members. Da Silva and Birch’s shared lead vocals on an ingenious cover of the Kinks classic “Lola” introduce another thrilling layer of gender confusion to a song that thrives on subverting the binary.

“Hits”

Go-Go’s — “We Got the Beat” (1981)

Formed just a few years after the Runaways, in the same city, the Go-Go’s made the transition from ’70s punk to ’80s new wave with their massively popular 1981 debut, Beauty and the Beat. Its signature single, “We Got the Beat,” exemplifies the band’s winning formula: angular surf riffs + exuberant vocal harmonies + an unlimited supply of rock attitude. Their success helped propel a raft of women-powered new wave groups to fame, from the Bangles to Bananarama.

Throwing Muses — “Dizzy” (1989)

Like Girlpool, Throwing Muses began with a pair of BFF teenage prodigies who shared singing and songwriting duties: stepsisters Kristin Hersh and Tanya Donelly. The band came up amid the New England indie boom of the mid-’80s and scored its first and biggest hit with “Dizzy,” from 1989’s Hunkpapa. A romantic Acid Western of a song, its choruses showcase the way Donelly’s airy harmonies complement Hersh’s throaty lead vocals.

The Breeders — “Cannonball” (1993)

In the early ’90s, the rising tide of grunge lifted… well, not all, but many indie boats. Suddenly, sisters Kim and Kelley Deal were working their way up the Billboard Hot 100 with “Cannonball,” a bigger hit than Kim’s former band, Pixies, ever released. (Throwing Muses’ Tanya Donelly was a founding member of the Breeders, too, but left before they achieved mainstream success.) Along with a sly bassline, it’s the Deals’ dual lead vocals that makes the song so alluring. There’s some kind of sibling magic in the way their voices slide over and around each other, adding contrast and echo that could actually be replicated in a live setting.

Veruca Salt — “Volcano Girls” (1997)

Veruca Salt emerged as the grunge era was winding down and so-called “angry women,” like Alanis Morissette and the Lilith Fair set, began occupying rock’s frustratingly narrow “woman as trend” fixation. The band featured two hardy sets of lungs in frontwoman Nina Gordon and guitarist/co-vocalist Louise Post. “Volcano Girls” pairs up their voices in a gesture of quasi-supernatural solidarity, with a chorus that will make you believe they really did just fight their way out of a pool of lava.

Sleater-Kinney — “Words and Guitar” (1997)

It’s a testament to Sleater-Kinney’s unparalleled discography (and, honestly, their lack of a standout chart hit) that just about any of their songs could’ve made it onto this list. But it feels fitting to celebrate the interplay between Corin Tucker’s emotive wail and Carrie Brownstein’s grounded murmur with “Words and Guitar”—a passionate love song to rock itself—from their third (and greatest) album, Dig Me Out.

Hidden Gems

Delta 5 — “Mind Your Own Business” (1979)

To the extent that this radical Leeds post-punk quintet is still remembered in 2017, it’s for this debut single—a brutal, monotone kiss-off that has bassists Bethan Peters and Ros Allen singing in militant lockstep with frontwoman Julz Sale. No wonder this timeless tale of a woman who just wants to be left alone became a sort of standard for female-dominated bands, with everyone from Dum Dum Girls to Chicks on Speed releasing covers.

LiLiPUT — “Split” (1980)

Switzerland’s LiLiPUT (originally known as Kleenex) never earned quite the same following as their late-’70s/early-’80s contemporaries in America and the UK. And that’s a shame, because the mostly female post-punk act had a unique way of spinning vibrant, kinetic chaos out of overlapping and contrasting shouts on singles like “Split.”

Excuse 17 — “Watchmaker” (1995)

Fans of Sleater-Kinney owe it to themselves to get into Excuse 17, Carrie Brownstein’s early-’90s queercore act. Like S-K, the band split vocal duties between Brownstein and a champion screamer—in this case, Becca Albee. On “Watchmaker,” their ahead-of-its-time rejoinder to mansplainers, Brownstein dispenses deadpan verses, then passes the mic to Albee for the song’s blistering choruses.

All Girl Summer Fun Band — “Later Operator” (2002)

This unjustly forgotten mid-’00s indie-pop supergroup—featuring Jen Sbragia of the Softies and Kathy Foster of the Thermals, among other Portland music-scene fixtures—sounds just as warm and breezy as its name implies. “Later Operator” has the women trading goofy boyfriend stories and harmonizing in vintage girl group-style choruses so catchy, they’re fit to be reprised around a campfire.

The New Class

Haim — “The Wire” (2013)

Yet another sister act, Danielle, Este, and Alana Haim started playing together in a family cover band called Rockinhaim when they were just kids. Irresistible hooks and sisterly magnetism aside, the secret to Haim’s success is harmonies that blur the line between jaunty ’80s pop-rock and sultry R&B—as seen on the single that vaulted them into the mainstream, “The Wire.”

Ex Hex — “Don’t Wanna Lose” (2014)

Helium, Autoclave, Wild Flag—has any musician of the past three decades been in more great bands than Mary Timony? Her latest trio, Ex Hex, is an all-woman tribute to the larger-than-life riffs of ’70s glam and power pop. Their single “Don’t Wanna Lose,” a self-assured ultimatum to a fickle lover, doubles its swagger when bassist Betsy Wright backs up Timony on the chorus.

Girlpool — “123” (2017)

When Tucker and Tividad sing in unison, the full force of their voices lends a rare urgency to the vivid imagery that suffuse their lyrics. On the first single from Powerplant, those bold choruses are interspersed with whispered verses to haunting effect—but there’s also an anthemic quality to the song, with riffs that bring Girlpool further than ever from their folky roots.