Tens of thousands of people took to the streets this Earth Day as part of March For Science rallies held in dozens of cities across the country. Inspired by the Women's March on Washington, organizers behind Saturday's March For Science are hoping to send lawmakers an important message about the importance of funding scientific research and making policies based on evidence rather than ideology. In many cities, the event has draw sizable crowds with photos from March For Science rallies show fact-loving science nerds have perhaps the best sense of humor.

"We're gathered here today to fight for science," the Washington Post reported science communicator Cara Santa Maria told the crowd gathered April 22 at the March for Science rally in Washington, D.C. "We're gathered to fight for education. To fight for knowledge. And to fight for Planet Earth."

Organizers behind the march have characterized it as "the first step of a global movement to defend the vital role science plays in our health, safety, economies, and governments." And although the event's website and mission statement don't explicitly mention President Donald Trump, his recent efforts to roll back Obama-era environmental regulations and slash funding for scientific research clearly helped inspire the creation of the march.

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"People who value science have remained silent for far too long in the face of policies that ignore scientific evidence and endanger both human life and the future of our world," organizers said in a statement about the march's mission. "New policies threaten to further restrict scientists' ability to research and communicate their findings. We face a possible future where people not only ignore scientific evidence, but seek to eliminate it entirely. Staying silent is a luxury that we can no longer afford."

But while the March For Science certainly has a political message, organizers have said it's not meant to be one of partisan criticism. "It's not about the current administration," Fox News reported co-organizer and public health researcher Caroline Weinberg said. "The truth is we should have been marching for science 30 years ago, 20 years, 10 years ago… The current [political] situation took us from kind of ignoring science to blatantly attacking it. And that seems to be galvanizing people in a way it never has before."

In Washington, the March for Science rally also included a slew of teach-ins organized by the Earth Day Network and geared at preparing participants for future political activism actions. Topics included "Protecting Wildlife in an Era of Climate Change," "How to Stop Your Climate Denialist Uncle in His Tracks," and "Communicating Science in a Politicized World." Organizers told the New York Times they hoped participants would be encouraged to continue advocating for science and evidence-based policymaking well beyond Earth Day.

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March for Science rallies were held in more than 500 cities around the world, including Los Angeles, New York, Reykjavik, and Rio De Janeiro.