Demonstrators hold placards during the "March for Science Stockholm" manifestation at Medborgarplatsen square in Stockholm, Sweden. TT News Agency/Marc Femenia/via REUTERS

Demonstrators march to the U.S. Capitol during the March For Science in Washington, U.S., April 22, 2017. REUTERS/Aaron P. Bernstein

Demonstrators attend the March for Science rally on Earth Day, in Santiago, April 22, 2017. REUTERS/Ivan Alvarado

Mary Devine of Levittown, Long Island looks on during the Earth Day 'March For Science NYC' demonstration to coincide with similar marches globally in Manhattan, New York, U.S., April 22, 2017. REUTERS/Andrew Kelly

Demonstrators gather at the Washington Monument before marching to the U.S. Capitol during the March for Science in Washington, U.S., April 22, 2017. REUTERS/Aaron P. Bernstein

Demonstrators gather as they participate in the March for Science rally on Earth Day, in Santiago, April 22, 2017. REUTERS/Ivan Alvarado

A demonstrator rides the carousel at the March for Science rally on the Common in Boston, Massachusetts, U.S., April 22, 2017. REUTERS/Brian Snyder

Demonstrators march to the U.S. Capitol during the March for Science in Washington, U.S., April 22, 2017. REUTERS/Aaron P. Bernstein

A protester dressed as U.S. president Donald Trump pretends to play golf with the Earth during the Earth Day 'March For Science NYC' demonstration to coincide with similar marches globally in Manhattan, New York, U.S., April 22, 2017. REUTERS/Andrew Kelly

Demonstrators march down Commonwealth Avenue from Massachusetts Institute of Technology (MIT) to the March for Science rally on the Common in Boston, Massachusetts, U.S., April 22, 2017. REUTERS/Brian Snyder

A demonstrator wears an Albert Einstein image at the March for Science rally on Earth Day, in Santiago, April 22, 2017. REUTERS/Ivan Alvarado

Volunteers hold their fists in the air during the March For Science in Seattle, Washington, U.S. April 22, 2017. REUTERS/David Ryder

Women dressed as witches join the March for Science rally on the Common in Boston, Massachusetts, U.S., April 22, 2017. REUTERS/Brian Snyder

Bill Nye leads demonstrators on a march to the U.S. Capitol during the March for Science in Washington, U.S., April 22, 2017. REUTERS/Aaron P. Bernstein

A protestor holds a sign in support of science during the March For Science in Seattle, Washington, U.S. April 22, 2017. REUTERS/David Ryder

Demonstrators gather for the March for Science rally on the Common in Boston, Massachusetts, U.S., April 22, 2017. REUTERS/Brian Snyder

A protestor, who attempted to disrupt the official rally program, is detained by police officers during the March For Science in Seattle, Washington, U.S. April 22, 2017. REUTERS/David Ryder