Microbe or Mineral?

Over the past couple years, a few pounds of rock from Australia have been the subject of a fierce scientific battle between geologists and paleontologists. Some paleontologists have claimed that microscopic marks in the 3.5 billion year old rocks are the oldest fossils of life yet found. Some geologists have recently argued that the marks are just odd mineral formations that could have been created without the help of life. Today in Science, the geologists have struck again. A team from Spain and Australia mixed up some silica, carbonate, barium, and other compounds that can be found in the Australian rocks. With a little lab cooking (which they argue is akin to how the rocks formed) they were able to create little lumpy chains. When UCLA's William Schopf discovered similar little lumpy chains in 1993, he declared that he had found fossils of cyanobacteria (also known as blue-green algae). Not ...