She is known for playing passionate women who fight for their chosen cause, but in real life, Hollywood actress Sigourney Weaver is equally relentless in her work as a zoologist and  conservationist. From saving the gorillas to protecting our oceans, the actress is devoted to bringing about real change.

It is not unusual for actors to temporarily “become” the person whom they are portraying, but when Hollywood star Sigourney Weaver took on the role of murdered primatologist Dian Fossey, it launched the actress on a lifelong conservation mission that has continued long since the cameras stopped rolling. Twenty-eight years later, her environmental endeavors have gone beyond advocating for the protection of the mountain gorillas, though she still serves as Honorary Chairperson of the Diane Fossey Gorilla Fund International. She is now also committed to raising awareness about the threats faced by marine wildlife and empowering women in extreme poverty through the nonprofit organization Trickle Up.

“After spending so much time with the mountain gorillas in Rwanda and playing Dian, I felt that I had been given a gift. It’s appropriate that I try to do whatever I can to help protect them,” explains Weaver, describing how her environmental crusade began. The 1988 drama tells the true story of Dian Fossey, a naturalist who worked in Rwanda with mountain gorillas. Prior to her work in the Virunga Mountains, Fossey had spent time in the Congo studying the primates. Having become frustrated at her inability to get close to them, she eventually used her experience of working as an occupational therapist with autistic children, discovering that when she mimicked the primates and became submissive, they would respond better to her. By the time she began her work in Rwanda in 1967 and founded the Karisoke Research Centre, Fossey was entirely devoted to protecting the animals and was horrified by the practice of poaching in the area, despite it
being illegal. Over the next 18 years, Fossey would help arrest several poachers, who went on to serve lengthy jail sentences.

She even founded her own poaching patrols, and in 1978 tried to prevent two infant gorillas, Coco and Pucker, from being exported to a zoo in Cologne, Germany. Naturally, her incredible efforts caused tension among the local gangs and poachers, and in 1985 (aged 53) Fossey was found bludgeoned to death in her cabin on the outskirts of the camp. The story of Dian Fossey is so extraordinary that little embellishment was required. Even her relationship with National Geographic photographer Bob Campbell was based on fact. Weaver was dedicated to bringing to life the tale of the woman who essentially saved these mountain gorillas from extinction at the cost of her own life, even if, at times, the actress admits she felt utterly out of her comfort zone. “The truth is,” she explains, “I didn’t really know how I would react to the gorillas. I had no experience with wild animals. But I knew that in order to play the part [of Dian Fossey], which I wanted very much to do, and in order to get Dian’s message out, there was no time for me to worry about what was going to happen. I remember I was pretty excited when we finally reached a place with gorillas.”

The film seamlessly blended moments of actual gorillas in their live habitats with scenes of humans in costume. Even so, there were plenty of scenes where Weaver would interact with actual gorillas. Not only did this add authenticity to the film, it also helped Weaver understand Fossey’s own motives and commitment to helping them. “The first time you see the mountain gorillas, you feel so blessed; you feel like you’re in Eden. One of them, a little female named Josie, came right over and sat next to me. She kind of leaned on me and looked up at me. I was just captivated. I never looked back after that,” says Weaver wistfully. “I always felt that if I followed Dian’s basic rules of being submissive and quiet, not drawing attention to myself and being respectful, nothing would ever happen to me.”

It is a bitter irony that the real Dian Fossey spent so much among these wild – and presumed dangerous – creatures, and yet met her death at the hands of humans. Weaver admits that the time spent among the gorillas not only galvanized her desire to protect them but also triggered her own maternal instincts, saying: “Playing Dian, I would usually have several little baby gorillas jumping up and down on me, pulling my hair, urinating on me, grabbing my bag…. And I had so much fun with them, and I loved them so much; I remember thinking, ‘I would really like to be a mother!’ I got hooked on being a surrogate mother, roughing it in the hills of Rwanda, and I had my daughter pretty soon after that.” Over the past three decades, she has cemented her place among Hollywood’s elite and has garnered a reputation for playing and formidable females, especially in her most famous role as Ellen Ripley in the Alien franchise.

The planet Earth has its own life force – the oceans. Our oceans generate most of our oxygen, regulate our climate, and provide most of our population with sustenance.

However, it would be another film featuring extraterrestrials that would inspire Weaver to once again speak out on conservational matters, this time on behalf of our marine life. In CGI behemoth Avatar, she plays Dr. Grace Augustine, a scientist who has dedicated her life to analyzing the links between the alien Na’vi people and the peculiar environment on Pandora. Similarly, Weaver
is determined to compel lawmakers to enact legislation to save our oceans. “The planet Earth has its own life force – the oceans. Our oceans generate most of our oxygen, regulate our climate, and
provide most of our population with sustenance,” explains Weaver, who narrated the 2010 documentary ACID TEST: The Global Challenge of Ocean Acidification as part of her work on
behalf of the Natural Resources Defense Council.

“Marine ecosystems are essential to all life on earth,” Weaver says. “Yet our oceans face a threat as dangerous as any Pandora faced: ocean acidification.” The film explores the startling
phenomenon of the increasing acidity of our waters and the subsequent threat to marine life. Like global warming, ocean acidification stems from the increase of carbon dioxide levels
in the Earth’s atmosphere since the start of the Industrial Revolution.

Leading scientific experts on the problem – many of whom appear in the film – believe that it is possible to cut back on global warming pollution, improve the overall health and durability of our oceans, and prevent serious harm to our world, but only if action is taken quickly and decisively. Weaver insists that we simply cannot act fast enough. “One of the reasons that science fiction movies are becoming more and more popular is because we are actually in a world more and more like the worlds in science fiction. Our glaciers are melting and people are talking about colonizing Mars – so I think that not only will it become a very popular and beloved genre but also increasingly significant.”

The problem with ocean acidification is that while, individually, we can all do our part to lower our own carbon footprints, for the most part it is the lawmakers and politicians who need
to bring in legislation and devote money to monitoring and researching a problem that could prove devastating, not just for sea life but for our ecosystem in its entirety. By urging politicians to support America’s transition to a clean-energy economy, Weaver insists that America can increase its energy efficiency and invest in renewable power while cutting carbon pollution. By passing strong clean-energy and climate legislation, Congress has the power to move society toward clean energy, tackle climate change, and protect our seas from acidification.

“Small creatures in the ocean who are being affected by acidification are like the canaries in the mine. They’re singing, and we have to hear that and act,” insists the actor. “I, like a lot of concerned citizens, feel a kind of urgency about these climate questions. I don’t think I’ve ever felt more passionately about anything than this because I feel we’re already at a tipping point.” In 2011 Weaver received the prestigious Rachel Carson Award from the National Audubon Society. The award was established in honor of Rachel Carson – a monumental figure in the 20th century and founder of the modern environmental movement – and aims to honor American women whose work has greatly advanced conservation, locally and globally.

In Weaver’s acceptance speech, she credited her experience working with mountain gorillas in Rwanda for inspiring her environmental and conservation work, emphasizing that it taught her the
importance of preserving animal habitats. She also credited her role in Avatar as a botanist who champions the natural world for intensifying her commitment toward protecting the Earth. But surely it is us who should be thanking Weaver for her admirable efforts in striving to protect something that is arguably invaluable to each and every one of us.