In troubling times, some people may wonder about the idea of multiverses–where other versions of us and our reality are playing out, but perhaps differently–and whether we’re in a particularly bad iteration. The real question, writes George Musser, author and contributing editor of Scientific American, is not whether there are other so-called timelines: according to quantum physics, there almost certainly are. The real question is why we experience only one reality (for better or worse). 

On the nature of our reality: Human comprehension–and perhaps life itself–could not accommodate the knowledge of every possible outcome of existence, Musser speculates, especially considering their infinitudes.  

What the experts say: One of the key insights of physicist Hugh Everett, originator of the multiverse-spawning "many worlds" interpretation of quantum mechanics, concerned the consequences of humans being part of the reality we hope to observe. Because we are embedded in the system, Everett argued, we can never observe other branches of reality firsthand. "Rather than holding open all possibilities, a mind must settle—at least tentatively—on one," writes Musser. "The effort required to make that choice—and, from there, to act upon it—may be key to giving us at least the subjective feeling of free will." 

Researchers took a close look at the Komodo dragon’s 60 serrated teeth, each up to an inch long. They observed an orange discoloration on the outer layer of the teeth. Using chemical and structural imaging the scientists discovered that the orange coating is iron. It’s the first confirmed finding of iron on reptilian teeth. (Some fish and salamanders, as well as a handful of mammals—most notably beavers—are also known to include iron in their teeth.)

How it works: The tip of each pointed Komodo dragon tooth curves back into the animal’s mouth, which lets the animal tear off and swallow chunks of meat (*shudder*). The iron reinforces this structure and runs down the front and back of each tooth.

What the experts say: “Now that we’re starting to actually take a closer look at different reptiles, we’re finding all of these really cool adaptations,” says Kirstin Brink, a paleontologist at the University of Manitoba.