Among the ambitious works staged at the 2016 edition of Toronto’s Luminato festival, Song of Extinction struck a particularly powerful and timely note, due in large part to the emotional musical journey through geological time created by composer Rose Bolton.

Described as an immersive visual and sonic exploration of the Anthropocene era (the newish buzzword many now use for our current epoch), the 50-minute, multi-media production encompassed many of the forms Bolton has been engaged with during her impressive, productive career: chamber music (performed by Music in the Barns Chamber Ensemble); vocal music (Tafelmusik Chamber Choir members, and VIVA! Youth Singers); pop music (“using a popular song format, with lyrics and vocals front and centre,” she explains); and live electronics (executed by Bolton).

Song of Extinction evolved out of a collaborative back-and-forth between documentary filmmaker Marc de Guerre, Order of Canada-inducted poet Don McKay, Music in the Barns director Carol Gimbel, and Bolton. It continues the exploratory method Bolton’s enjoyed since age nine, when she played every instrument she could get her hands on (from piano to violin to Salvation-Army brass instruments) and started to write music.

Awards and commissions came early to Bolton, who received a Bachelor of Music degree from the University of Western Ontario in the early 1990s, then took a couple of years off to study privately with Toronto composer Alexina Louie and write. She then earned her Masters in Composition at McGill University, which she completed in 1998. Bolton had relished her creative adventures in the electronic-music studios of Western and McGill, but she kept getting commissions for instrumental work and picking up accolades along the way, such as the Toronto Emerging Composer Award in 2001.

In 2005, after a busy year that included the world premiere of a major commission for Esprit Orchestra, she took a step back. “I started to look at my body of work up to that date and realized that I wanted to have control over the future of my own writing,” she recalls. “In those early years, I allowed commissions to guide me. I also got involved in traditional Irish and fiddle music, I played in a country band and folk ensembles, wrote orchestrations for pop bands. It was all about being part of a scene – playing gigs, then being a composer. It was great, it kept me busy. And I didn’t have to think about what I should be doing.

“But I wanted to be more like painters, who create a work and then it exists, and they don’t have to give it to someone who renders it,” she continues. “So I got serious in 2005 and started building my own studio. [Graphical modular software music studio] Reaktor started to happen, so all I needed was a better computer. I got an early version of Logic, and a digital recorder to collect samples. By 2007 I had a commission.”

Bolton now spends half the year composing score music for her partner Marc de Guerre’s artful social-history-themed docs, such as Who’s Sorry Now (CBC, 2012) and Life After Digital (TVO, 2014), and the other half writing concert music (both commissions and personal music). Her studio light is pretty much always switched on.

When she started working in film eight years ago, she would create early sketches. “But often you don’t know what the mood is going to be before the film is edited, you might only have a few minutes of footage,” she explains. “For the documentary genre, Marc likes electronic music, and I often end up blending in instruments. I’ve developed my skills of how to produce and mix – the whole process has really changed the way I think about music.

“As a concert composer, if you’re commissioned to write music for a string quartet, once you know who you’re writing for… that’s it,” she laughs. “But when I’m doing a documentary soundtrack, sometimes an instrument won’t work, so I try different sounds – try a horn, try a synth, try a sample, let’s try bells! But with a commission, well, you can’t fire your horn player!”

Bolton says de Guerre, who was a visual artist before turning to film, had the idea for Song of Extinction a few years before they met. As they began to discuss his ideas, Bolton knew she wanted to use a chamber choir and instruments, but the music didn’t take shape until she began working with McKay. “I had music sketches, he would write a poem and send it back – poetry and music were happening simultaneously,” she recalls. “Don would say, ‘You can do what you want with the words,’ so I would turn his poem into something more like song lyrics, boil it down to its essences, which he was fine with.”

The ideas for the instrumentation kept changing until Music In The Barns came on board, but Bolton always intended to use a chamber choir. “My idea was to have humans singing about extinction,” she says. “In the end, we had singers from Tafelmusik and 30 singers from a youth choir. So they would sing together, as opposed to having a soloist, and the two choirs would sing back and forth, similar to human discussion among friends or on the news.

“There’s always a back and forth,” she says. “It’s the way that ideas take shape.”