> It's weird that we don't know what teeth were like before fluoride was invented. We have teeth from fossils that are a few thousand years old all the way to

> It's weird that we don't know what teeth were like before fluoride was invented. We have teeth from fossils that are a few thousand years old all the way to over a million years old. https://www.npr.org/templates/story/story.php?storyId=1295624 https://www.npr.org/templates/story/story.php?storyId=129562... https://www.smithsonianmag.com/science-nature/oldest-human-fossil-unearthed-ethiopia-180954470/ https://www.smithsonianmag.com/science-nature/oldest-human-f... https://www.nationalgeographic.com/news/2018/01/oldest-human-outside-africa-discovered-fossil-jaw-israel-science/ https://www.nationalgeographic.com/news/2018/01/oldest-human...