Koalas and Bicycles

Koalas rely on special gut microbes passed from mothers to babies through a unique form of poop, but rising chlamydia cases threaten this delicate balance. In a surprising twist of history, the invention of the bicycle emerged as a response to climate change, stemming from the catastrophic effects of the 1815 Mount Tambora eruption, which led to a year without summer and a need for alternative transportation.