Hyenas may be using bacteria to communicateS  We all have
bacteria that live in our bodies, helping us by breaking down
food, flushing out toxins, and regulating our weight. But for
hyenas and other animals with specialized scent glands, bacteria
may have an additional, important role: They could be allowing
hyenas to communicate with each other.  Top image via Chris
Eason/Flickr.  The Birth of the Fermentation Hypothesis  Back in
the mid-1970s, two groups of researchers were analyzing the anal
scent glands of different animals, including small Asian
mongooses, red foxes and lions, when they stumbled upon
something interesting. They found that a prominent component of
the animals' communicative scents were short-chain fatty acids,
a type of molecule produced by fermenting bacteria.  This
discovery birthed the "fermentation hypothesis," said Kevin
Theis, an ecologist at Michigan State University. The hypothesis
proposes that the scented components in many mammalian chemical
signals are the byproducts of the fe