Tens of thousands of scientists and science supporters took to the streets Saturday for the March for Science, standing up for an intellectual framework that's done everything from measure the age of the universe to let you send a text message to your mom.

Marches and speeches took place across the US -- in Washington, New York, San Francisco, Seattle, Los Angeles and Chicago -- and elsewhere in the world, in cities including London, Paris and Sydney.

Organizers of the officially titled March for Science were careful to bill the event as nonpartisan, but many marchers clearly had President Donald Trump and his administration's priorities in mind. At the march in San Jose, California, one chant went, "Ho ho, hey hey, don't defund the EPA," a reference to a massive budget cut proposed for the nation's Environmental Protection Agency.

The Trump administration also has been openly skeptical of the scientific consensus about climate change and global warming.

Trump responded to the marches, which took place on Earth Day, with a statement: "Rigorous science is critical to my administration's efforts to achieve the twin goals of economic growth and environmental protection."

Marchers evidently felt science and the scientific method is under attack. But they argued that in the long run, reality wins out over unfounded opinions. At the San Jose march, one quote from astrophysicist and Cosmos TV show host Neil DeGrasse Tyson proved popular on signs and T-shirts: "The good thing about science is that it is true whether or not you believe in it."

And they embraced the principles of science, including the peer-review process by which researchers scrutinize and validate research before it's published in journals. Such reviews, though not perfect, are key to spotting mistakes or even fraud and thus zeroing in on the truth.

Went one chant at the San Jose march: "What do we want? Science! When do we want it? After peer review!"

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