5 Most Incredible Discoveries of the Week A sad discovery ... along with a more hellish one By Newser Editors, Newser Staff Posted Jul 4, 2015 5:26 AM CDT 1 comment Comments The Wall isn't doing so hot. (Shutterstock) (Newser) – An eye color linked to hitting the bottle and bad news about the Great Wall of China make the list: Sniff Test May Help Diagnose Autism: A simple sniff test shows promise in detecting autism in kids—perhaps even in those who aren't yet toddlers because it doesn't involve responding to questions. Instead, it involves how kids respond to strong odors, even pleasant ones. One Eye Color Is Linked to Alcoholism: A study out of the University of Vermont suggests a genetic link between alcoholism and people with blue eyes. Scientists aren't sure why, but it might have something to do with where the genes linked to both traits are found. Great Wall of China Is Disappearing: Meaning 1,219 miles of the wall have come down, with another 736 miles in a sorry state, per the country's State Administration of Cultural Heritage. That former figure is about 30% of the wall's artificial length—and these numbers may not even be a true reflection of how bad things truly are. 'Centipede From Hell' Lurking in Caves: Meet Geophilus hadesi—or "Hades," named for the Greek god of the underworld—a subterranean centipede discovered in the Velebit mountain range. The carnivore eats other invertebrates and has jaws filled with poison. But there's something that really makes this "centipede from hell" unique. Scientists Tell You How to Pet Your Cat: Yes, it turns out there is a right and wrong way to pet a cat, per researchers from UK's University of Lincoln. Kitties seem to like being stroked between their eyes and ears, but there's one particular area that "is sort of a cat erogenous zone, and petting may overstimulate it." Click to read about more discoveries, including how a new test can precisely determine a person's time of death.