From Will Sullivan at PBS Nova Next:
While the single-celled organisms that dominated early Earth’s oceans didn’t have much need for teeth, they did find some evolutionary advantage in making their own minerals. According to research published last week, life has been making its own hard parts for at least 810 million years, about 200 million years longer than previously thought. It’s the first occurrence of what scientists call biomineralization, and it could give us deeper insight into both the evolution of living things and Earth’s early climate. More.
It also reduces the time for purely Darwinian evolution to work.
See also: Stasis: Life goes on but evolution does not happen