Three days later, Rory died of sepsis after bacteria from the scrape infiltrated his blood and triggered organ ... an extra set of eyes and ears—and help them make better decisions.

But during they day when they're resting, they can make their skin and muscles transparent. New research has shown that they do this by removing red blood cells from circulation, and hiding those ...

"If you really want to be transparent, you need to hide your red blood cells," study co-author Sönke Johnsen, a professor of biology at Duke University in North Carolina, told Live Science.