As many dentists know, overbites are rather commonplace today. However, even the dental profession’s keenest historians may be unaware that our Stone Age ancestors once sported much straighter smiles, with top and bottom teeth that didn’t overlap. And only recently have researchers begun to consider why overbites are currently so prevalent.
The theory of evolution was famously outlined by British naturalist Charles Darwin in his epochal 1859 work On the Origin of Species. In the book, Darwin suggested that life forms change over long periods of time as a result of natural selection. And owing to this process, organisms that are well adapted to their environments live for longer and pass on more of their genetic traits to the next generation than those that fail to acclimatize to their surroundings.
Eventually, then, and with enough changes, natural selection is able to create a whole new species. This process is called macroevolution, and it’s thought to be responsible for a number of animals that we know today. Yes, macroevolution is said to have been key in creating birds from dinosaurs, whales from amphibious mammals and humans from ancient apes.