Royal Incest: Week's 5 Most Incredible Discoveries Including an expectation-defying fish By Jenn Gidman, Newser Staff Posted May 16, 2015 5:37 AM CDT 0 comments Comments In this undated photo released by the Egyptian Supreme Council of Antiquities the 3,000-year-old red granite head believed to be that of 19th Dynasty pharaoh Ramses II is seen. (AP Photo/Egyptian Supreme Council of Antiquities, HO) (Newser) – Chalky chocolate, a most unusual fish, and proof of incest make this week's list of incredible discoveries: Scientists Find Proof of Pharaohs' Incest: A new study has found that "pharaohs varied less in height than men of the common population," as a researcher explains—a rather plain statement with some pretty gossipy implications. Swiss researcher Frank Rühli and his colleagues examined the height of 259 mummies—a group that included rulers and common folk—in a search for proof of incest, and they say they've found it. Meet the World's First Warm-Blooded Fish: Your science teacher was wrong: It turns out that not all fish are cold-blooded. Scientists have discovered that the opah, a deep-sea dweller also known as the moonfish, is, in fact, a warm-blooded creature and the first such fish ever found. Here's how that's possible. What Happens When a Working Couple Has a Kid: Ohio State University researchers took a look at dual-earner straight couples on the path to parenthood. Pre-baby, the men and women tended to work just over 40 hours a week and log a pretty equal 15 hours of household work. "These are the couples you would expect to have the most egalitarian relationships," is how a researcher put it. That's not what happened post-baby. Song Stuck in Your Head? Do This: Getting a song stuck in your head is no modern conundrum, with even Edgar Allan Poe complaining in 1845 that it is "quite a common thing" to be "annoyed" or even "tormented" by "the burthen of some ordinary song." Now researchers at the University of Reading report that doing this simple thing might help alleviate said burden. X-Ray Solves Mystery of Chalky Chocolate: Have you ever thrown out old chocolate that had taken on a chalky, white hue, unsure if it was still edible? You're not the only one. Food scientists say the harmless change, known as fat blooming, is a major source of complaints and actually costs the confectionary industry millions. The process was also largely a mystery until German scientists decided to take a closer look. Click to read about more discoveries.