In Porto Velho, capital of a Brazilian state ravaged por recent fires, residents are on edge and falling ill from the pervasive smoke. A hymn describes the city's sky as forever blue, but now it's grey with smoke.
added by lilyZ
Fossils are echoes of an ancient past. Find out about the two major categories of fossils, how fossilization occurs, and how fossils can help paint a picture of the planet's history.