Scientists mark Earth Day with March for Science in DC (Photos)

A man stands by a sign that reads “Science and Revolution” at the March for Science event near the Washington Monument in Washington, Saturday, April 22, 2017. Scientists, students and research advocates rallied from the Brandenburg Gate to the Washington Monument on Earth Day, conveying a global message of scientific freedom without political interference and spending necessary to make future breakthroughs possible. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Ellen Taylor from Albany, N.Y., poses with an Albert Einstein mask for a portrait at the March for Science event in Washington, Saturday, April 22, 2017. Scientists, students and research advocates rallied from the Brandenburg Gate to the Washington Monument on Earth Day, conveying a global message of scientific freedom without political interference and spending necessary to make future breakthroughs possible. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

People arrive at the March for Science event near the Washington Monument in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Erin Greeson with the Planetary Society, center, and Bill Nye “The Science Guy” right, talk backstage at the March for Science event near the Washington Monument in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Mondrian Shumate, right, from Belfast, Maine, attends the March for Science event near the Washington Monument in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

A crowd gathers for the March for Science in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Erin Greeson with the Planetary Society and Bill Nye “The Science Guy” talk backstage at the March for Science event in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Conall Spaur from Howell, N.J., holds a sign while waiting in line for a teach-in on climate change at the March for Science event in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

A person hold up a sign that reads “Fund Climate Change Research Saving The Planet Is Not A Waste Of Money” during the March for Science in Washington, Saturday, April 22, 2017. Thousands of scientists worldwide left their labs to take to the streets Saturday along with students and research advocates in pushing back against what they say are mounting attacks on science. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Retired U.S. Army Corporal Amy Schienschang from Williamsburg, Va., poses for a portrait with a sign that reads “A Woman’s Place Is In The Lab” at the March for Science event in Washington, Saturday, April 22, 2017. Scientists, students and research advocates rallied from the Brandenburg Gate to the Washington Monument on Earth Day, conveying a global message of scientific freedom without political interference and spending necessary to make future breakthroughs possible. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Laura Allen poses for a portrait with her children Shabbir and Nadiya at the March for Science event in Washington, Saturday, April 22, 2017. Scientists, students and research advocates rallied from the Brandenburg Gate to the Washington Monument on Earth Day, conveying a global message of scientific freedom without political interference and spending necessary to make future breakthroughs possible. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

Ben Prickril poses for a portrait with a sign that reads “Vaccines Save Lives By The Millions” at the March for Science event in Washington, Saturday, April 22, 2017. Scientists, students and research advocates rallied from the Brandenburg Gate to the Washington Monument on Earth Day, conveying a global message of scientific freedom without political interference and spending necessary to make future breakthroughs possible. (AP Photo/Sait Serkan Gurbuz)

AP Photo/Sait Serkan Gurbuz

March for Science protesters hold signs at the National Mall. (WTOP/Kathy Stewart)

A March for Science button sits in the rain. (WTOP/Kathy Stewart)

Earth Day in D.C. was expected to draw crowds of over 100,000 (WTOP/Kathy Stewart)

Earth Day at the National Mall this year includes "March for Science." Scientists from the University of Penn sport their lab coats. (WTOP/Kathy Stewart) — Earth Day on Nat’ll Mall this year includes “March for Science.” Here are scientists from the University of Penn sporting their lab coats. (WTOP/Kathy Stewart)

Earth Day on National Mall also "March for Science." March will start at Washington Monument and head Capitol later this afternoon.@WTOP pic.twitter.com/SCy02vREUP
— Kathy Stewart (@KStewartWTOP) April 22, 2017

(WTOP/Kathy Stewart)

Environmental videos playing before official program gets underway by Washington Monument for Earth Day and #marchforscience. @WTOP pic.twitter.com/6SdSjN2YTH
— Kathy Stewart (@KStewartWTOP) April 22, 2017

(WTOP/Kathy Stewart)

Among the participants at the #marchforsciencedc

A post shared by Kate Ryan (@kateryanwtop) on Apr 22, 2017 at 8:05am PDT

(WTOP/Kathy Stewart)

Protest, rally, demonstration? In DC, you know it's a thing when the entrepreneurs show up with some topical merch. #marchforsciencedc

A post shared by Kate Ryan (@kateryanwtop) on Apr 22, 2017 at 8:08am PDT

(WTOP/Kathy Stewart)

Along with the buttons and tee shirts: plastic ponchos and umbrellas are hot sellers. #marchforsciencedc

A post shared by Kate Ryan (@kateryanwtop) on Apr 22, 2017 at 8:10am PDT

(WTOP/Kathy Stewart)

No, the Snowy Owl and Cardinal are not having a slap fight, they're just enjoying a breeze before heading to the #marchforsciencedc as part of the regional #Audubon Society delegation

A post shared by Kate Ryan (@kateryanwtop) on Apr 22, 2017 at 8:14am PDT

(WTOP/Kathy Stewart)