Photos From the Science March, on Earth Day

"People are anxious about scientific integrity being eroded or diminished", said Valorie Aquino, co-chair of the national March for Science effort.

Thousands of protesters are expected to join scientists, researchers, engineers and mathematicians in demonstrations around the world on Saturday for the March for Science.

The promoters expressed some ambivalence about how much the scientific movement, which normally focuses on measurable facts and figures, should take on a more overtly political role. Triggered by concern over the rise of "alternative facts", marchers sought to present a united front, particularly against the roll back of environmental protection policies and apparent lack of support for climate change.

The "March for Science" festivities included "teach-ins" on the National Mall and parades in midtown Manhattan and hundreds of other cities and towns.

"Science protects the health of our communities, the safety of our families, the education of our children, the foundation of our economy and jobs, and the future we all want to live in and preserve for coming generations", organizers say on the March for Science website.

Threats to science are heightened in Turkey and elsewhere in Europe, said McEntee, who planned to march with geophysical scientists in Vienna, Austria.

Rallies and marches have become commonplace in Washington since the inauguration of President Donald Trump, but this one was unique. Marchers carried signs supporting sighs and some even carried dinosaur skeletons. "We speak up now because all of these values are currently at risk".

Brad Slocum, a materials engineer from Virginia, said he was anxious about funding for research.

Headlining the march was Bill Nye, who has been vocal in recent months since President Donald Trump has indicated that he will reverse most of his predecessor's pro-science agenda.

Trump's first budget proposed large funding cuts to the Environmental Protection Agency (EPA), National Institutes of Health (NIH), Department of Energy, National Oceanic and Atmospheric Administration (NOAA) and NASA's Earth science budget.

"We need to invest in people and the environment", he said.

Organisers said 11,000 people took part in an event in Berlin, which they said aimed to highlight the importance of science and evidence-based knowledge in democracies. "Every medical breakthrough, their food, clothing, our cellphones, our computers, all that is science-based", said Pati Vitt, a plant scientist at the Chicago Botanic Garden.

He said debates over climate change should not be based on ideology with disregard to economic growth.

"My administration is reducing unnecessary burdens on American workers and American companies, while being mindful that our actions must also protect the environment", Mr Trump said. "Science is truth, and it's the closest thing we have to truth", she said.

Doctor Who star Peter Capaldi and comedian Robin Ince were among those seen mingling with physicists, astronomers and biologists, numbering some 12,000 organisers said.

In London, demonstrators marched from the Science Museum to Parliament Square in Westminster, holding colourful placards supporting science.

Demonstrations are also scheduled in US cities including San Francisco, along with smaller towns like Dillingham, Alaska.

She says locally we should make good choices regarding the environmental and let California lawmakers know that supporting science and research is important to the community. And that seems to be galvanizing people in a way it never has before.

  • Carolyn Briggs