Only 161,00 metric tons of gold has been mined in the entire history of the world. Considering about 85 percent of the precious mineral is recycled, there’s a chance your jewelry may once have been part of an Incan headdress or Mycenaean face mask. Learn the ins and outs of this metal that humans have killed over for millennia.
There’s an emerging field in health care called medical ecology that’s concerned with understanding how the 100 trillion microbes living inside us keep us healthy. The field’s first breakthrough is the fecal transplant, taking poop from a healthy person and putting it into the gut of a sick person. It’s a real thing and it actually works.
Fracking, the process of breaking trapped resources like natural gas and oil from shale, has led to a revolution in energy production in the U.S. It’s also given rise to increasing worries that the process can have sweeping environmental impacts.