TORONTO -- Extinction isn't just a threat for plants and animals 鈥� it's also a danger for bacteria.
By analyzing fossilized fecal matter from 1,000 to 2,000 years ago, American scientists were able to determine which species of bacteria were lurking in the human body all that time ago.
More than one-third of the species they found had never been seen in the modern world, meaning they'd been driven into extinction at some point in the past two millennia.
Scientists say that our improved nutrition and sanitation practices helped wiped out these species 鈥� but as 愛污传媒 Science and Technology Specialist Dan Riskin explains in this week's Riskin Report, the bacteria now living in our guts are plenty dangerous themselves.
