University of Bologna

While we're used to seeing cigarette butts littering public roads, such butts may soon be making their way into those roads, strengthening them in the process. It's all part of a recycling effort, which should also reduce the need for road repairs.

Scientists have studied 50,000-year-old Neanderthal poop, and analyzed the DNA of microbes to determine their gut microbiome. Many species are still present in modern humans, revealing the "old friend" bacteria that may be most crucial to our health.