Life On Earth: A Losing Game of Whack-A-Mole?

Beyond three billion years ago, the fossil record of life on Earth gets very patchy. At 3.4 billion years ago, there’s fairly good evidence of mats of microbes. At 3.5 billion years, there are little globules that have been proposed to be bacteria but which some researchers consider just blogs of minerals. Earlier still there are shadowy isotopic hints–ratios of light and heavy carbon atoms that seem biological rather than volcanic–dating back as far as 3.8 billion years. These, too, are the sub