5 Most Incredible Discoveries of the Week Including a tip for worrywarts and how parchment DNA has something to say By Newser Editors, Newser Staff Posted Dec 13, 2014 12:57 AM CST Updated Dec 13, 2014 9:25 AM CST 1 comment Comments Old parchment can offer clues about the past, even if the words themselves can't be deciphered. (AP Photo / The Berkshire Eagle, Ben Garver) (Newser) – The mystery of skeletons found in shackles make the list this week: Scientists Near Creepy Ancient Arena Make Even Creepier Find: In France, there's an old Roman amphitheater that once hosted gladiator fights and had a "Door of the Dead" through which people would be carried to their burial. Now scientists have discovered some of the dead at a site near the arena, including five skeletons with iron chains around their ankles, wrists, or necks. The next mystery: how all of these people died. There's a Way to Stop Worrying So Much: It's pretty simple, too—go to bed earlier, according to new research. Scientists have long said that a good night's sleep is essential to overall health, but now they think that when we go to bed also matters. Old Parchment Offers Its Own Clues About the Past: We've always labored over the meaning behind the words scrawled on ancient pieces of parchment, but now researchers are starting to bypass the semantics and look directly at the parchment itself. Turns out the DNA from animal skins used to make writing material in years of yore is pretty useful to compare to DNA of today's animals. It's even providing clues about 18th-century agricultural practices. The Way You Walk Can Change Your Mood: John Cleese may have been onto something with his Monty Python silly walks ministry. New research suggests that if we purposefully walk with a spring in our step, we may be able to elevate our mood. Researchers put subjects on a treadmill, which doesn't sound like something that would necessarily induce throes of ecstasy—but they tested their theory in a fascinating way. There Once Was a Bunny-Sized Dino With Horns: Lots of horns. Little tiny ones all over its 3.5-pound body. And the recently named Aquilops americanus fossil discovered in Montana 17 years ago is so far the oldest horned dinosaur ever found in North America and has given scientists important clues about how dinosaurs migrated from Asia to here. Click to read about more discoveries, including a theory on when early humans mastered fire.