A scene from the 2014 movie "Nightcrawler," which tells the story of a local TV news station that becomes ever-more desperate for gory real-life video footage. Nightcrawler / Bold Films Over the last three days we saw a really clear example of the new world of news that Facebook is creating, whether you like it or not.

On Thursday, Mark Zuckerberg defended his decision to show a video of Philando Castile — a black man who was shot by the police at a routine traffic stop in Minnesota — on the Facebook Live video platform. It shows Castile covered in blood, dying next to his distraught girlfriend and her baby daughter. Facebook sometimes takes down videos that are overly graphic. But not in this case, Zuckerberg said:

The images we've seen this week are graphic and heartbreaking, and they shine a light on the fear that millions of members of our community live with every day. While I hope we never have to see another video like Diamond's, it reminds us why coming together to build a more open and connected world is so important -- and how far we still have to go.

Clearly, Zuckerberg believes it is important for everyone to see how the police behave when they draw their weapons on civilians.

The video — along with a stream of others showing white police officers killing unarmed or unresisting black Americans — has animated a widespread movement against police brutality in the US. It spurred a peaceful march in Dallas Thursday night that ended in bloodshed when a gang of maniacs began shooting at police officers, killing five.

It is not true to say that the Castile Facebook Live video caused the march that became a target for the Dallas snipers. But the extra exposure that Facebook gave that video certainly contributed support for the march, and the anger behind it. That's a good thing — people should protest when they see injustice.

The problem for news publishers — and anyone who wants their news served with a reasonable effort to rank stories by importance, not format — is that Facebook's preference for video is biasing the news in favor of stories with dramatic video and against those that do not have moving pictures.

This is not a neutral bias.

There are plenty of incredibly important stories that Facebook is downplaying in your news feed because the algorithm that controls it favours video over text or photos. These are some examples of stories where the available information is largely or exclusively in text-only format:

Each of these stories has potentially much further-reaching consequences than a police shooting. After all, the 2007-2008 global financial crisis was triggered by these same issues a decade ago, and they're (maybe) happening again now.

But you can't see them on Facebook Live.

Facebook has paid 140 publishers a total of $50 million to produce a guaranteed number of Facebook Live video posts, according to the Wall Street Journal. (Disclosure: Business Insider is one of the publishers.) In order to speed up adoption of Facebook Live, Facebook has altered its news feed ranking to downplay the reach of text and photo posts, and to extend the reach of native video and Facebook Live events.

That is why your news feed might suddenly feel like it's full of video.

Nicola Mendelsohn, Facebook's vice president for Europe, the Middle East and Africa, recently said she expected to see an historic "decline" of text as a medium for delivering information:

"We’re seeing a year-on-year decline of text … If I was having a bet I’d say: video, video, video. ... The best way to tell stories in this world— where so much information is coming at us—actually is video. It commands so much information in a much quicker period so actually the trend helps us digest more of the information in a quicker way."

Facebook's daily video views have gone from 1 billion to 8 billion over the course of a year. Text posts, meanwhile, are declining year-on-year, Mendelsohn said.

Katharine Viner, the editor of The Guardian, said she believes the news is becoming distorted by algorithm decisions at companies like Facebook:

"Social media companies have become overwhelmingly powerful in determining what we read and whether publishers make any money," she said. "The idea of challenging the wide-open worldwide web has been replaced by platforms and publishers who maximize the amount of time you spend with them and find clever ways to stop you leaving. That may be great news for advertisers and the platforms themselves, but it’s a real concern for the news industry."

On the one hand, these are merely the complaints of publishers who once enjoyed a firehose of free traffic pouring off Facebook. That firehose has been turned down in recent months as Facebook has shifted its emphasis toward posts from friends — and video. So take the complaints of media moguls with a pinch of salt.

Facebook was recently accused of biasing its "trending" section in favour of liberal news sources, and playing down news of interest to conservatives. That accusation has largely turned out to be false.

The video bias, however, is true. If Facebook continues to keep its thumb on the scale in favor of moving pictures you can expect to see a lot more visceral, live, compelling, and maybe even grueling human dramas in your news feed. There is no doubt that bloody mayhem goes viral more quickly than an analysis of central bank interest rate policy. And some of it — like the Castile shooting — will be incredibly important, because that video tells a story of police violence far more compelling than any description in words ever could.

But just remember: every live video in your feed is pushing down a non-video item simply because that item is not a video. Facebook's pro-video bias is real and deliberate, based on format not content. You won't know what you're missing — which is the worrying part.