A new study suggests that evolution was slowed due to low oxygen levels more than a billion years ago, according to a BBC news report. The idea has been around for years, and the researchers put it to the test by analyzing very old rocks’ chromium levels to determine prehistoric oxygen levels.
They discovered oxygen levels of only 0.1 percent of modern levels. The rocks’ chemical makeup changed around 800 million B.C. in tandem with rapidly increasing oxygen levels. The researchers say that although the cause for slow evolution is far from being determined, they believe that their study can lead to further research which could lead to more answers.
Top image: Ammonite of the genus “Hoploscaphites.” (Credit: BetacommandBot via Wikimedia Commons / CC BY 3.0)