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I thought it was going to be a wonderful day. My high school, Marjory Stoneman Douglas, was full of cheerful students -- many of whom were celebrating Valentine's Day with one another. Even those who didn't have a Valentine seemed like they could find reasons to smile.  283

If you're interested in fish who are scary-looking, poisonous and chock-full of elaborate defense mechanisms, look no further than the stonefish, a genus of fish that populate coastal waters of the Indo-Pacific region.As if their deadly venom and spiny exteriors weren't enough, scientists at the University of Kansas have found that stonefish also have a hidden switchblade on their face that they can flick out whenever they feel like they're in danger.Scientists call the bony, blade-like protrusion a "lachrymal saber," because it is located on a bone under the fish's eyes. Also, "lachrymal saber" is just a really metal-sounding name.William Leo Smith, associate curator and associate professor of ecology & evolutionary biology at KU, first started to understand how the lachrymal saber worked 15 years ago, when he was dissecting a stonefish he kept as a pet.This is a game-changerHe tells CNN the mechanism isn't just a cool new discovery (although it's that, too). It also changes the scientific understandings and classifications of this particular type of fish."It opens up these ideas of ecological questions. Muscular systems, bone systems, nervous systems all came together to form this. What led to its evolution or use?In other words, he says, "Why do we see this accumulation of so many horrible things on one fish?"The lachrymal saber is housed inside the fish's head, and they use their cheek muscles to deploy it. Though some stonefish are venomous, the saber is not.It could be a sex thing, tooSmith says he and his fellow researchers have reason to believe the saber isn't just for warding off predators: It could be a sex thing, too."There is evidence pushing towards that," he says. "They may use this in battles with other members of their species, like ram horns. It may also be involved in courtship behaviors."Oh, and the sabers glow."It's fluorescent green," Smith says. Since stonefish rely on camouflage for both protection and hunting prey, Smith doesn't think the fluorescence has a defensive purpose like, say, warning off predators.There are 134 described species of stonefish, and by Smith's observation, all of them have some form of lachrymal saber.  2202

If Marjory Stoneman Douglas High School were like any other school, you wouldn't think much of the freshly-painted burgundy hallways or the newly-installed 20-foot tall fences around the freshman building.If this were a normal student body, the eyes of the nation wouldn't be trained on their every move, and their summer break stories wouldn't include a tally of rallies, summits, nationwide tours and TV appearances.In any other place, in any other new school year, things would be as they were.But when your school is also the site of one of the deadliest school shootings in American history, nothing is ever really normal.Those fences, covered with "MSD Strong" and "Parkland Strong" banners, surround the shuttered building where a former student opened fire almost exactly six months ago. Those hallways are the same ones students rushed through on Valentine's Day as the gunshots rang out across campus.There are other changes, too.The school's swimming coach is now the athletic director, because the former AD was among those killed that day. There are now two principals at MSD, because the basic demands of running a school are now joined by the demands of managing a community in crisis.It's the little things like this; a change in paint color or a change in command, that reverberate outward like strange ripples, hinting at something bigger under the surface. 1383

I’m happy to report that Jill and I have tested negative for COVID. Thank you to everyone for your messages of concern. I hope this serves as a reminder: wear a mask, keep social distance, and wash your hands.— Joe Biden (@JoeBiden) October 2, 2020 256

In a season full of historic moments, the Vegas Golden Knights are moving on to the Stanley Cup Final.With a final score of 2-1, the Knights were able to hold off the Winnipeg Jets in Game 5 of the series.  219