Editor's note

As the world reels from the New Zealand mosque massacre, it’s worth remembering the many past incidents of murder, assault and other violence that were also streamed live on Facebook. In the past, social media researcher Jennifer Grygiel has called for a time-delay on livestreams to protect children from seeing online horrors. Now, though, Grygiel writes that it’s time for even stronger action.

Social movements from the Bolsheviks to #MeToo often seem to come out of nowhere – until all of a sudden they topple once-untouchable tsars and media titans. Harvard’s Cass Sunstein, who recently finished a book on social change, explains why they take us by surprise.

And, even as marijuana legalization widens, your pet on pot is not a good thing. Pets, particularly dogs, are attracted to the smell of marijuana edibles such as brownies and candies. It’s important to keep pot away from pets, writes veterinary toxicologist John Buchweitz of Michigan State University, because it can make them sick. And derivatives such as CBD can be a problem, too.

Jeff Inglis

Science + Technology Editor

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Facebook Live can be fun – or really scary. I'm friday/Shutterstock.com

Livestreamed massacre means it’s time to shut down Facebook Live

Jennifer Grygiel, Syracuse University

Children can't handle watching livestreamed massacres – and adults shouldn't have to.

Tarana Burke created #MeToo in 2006 but it didn’t emerge as a mass social movement until 2017. AP Photo/Damian Dovarganes

Why social movements like #MeToo seem to come out of nowhere

Cass Sunstein, Harvard University

From the French Revolution to #MeToo, social movements often burst into the mainstream with what seems like little warning. Cass Sunstein explains why.

Dogs don’t need pot or CBD or other marijuana derivatives. Harshad Rathod/Shutterstock.com

Your pet on pot, or even CBD: Not a good thing, a vet toxicologist explains

John P. Buchweitz, Michigan State University

As marijuana and its derivatives are sold legally in more states, pets are getting into pot, accidentally. And some owners are intentionally giving them CBD. A vet explains the dangers.

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