Humans have not evolved to be taller in the last three hundred years. While the average adult height has indeed increased in many countries over the last few hundred years, this increase was not caused by evolution. Additionally, the average height gain over the last few hundred years has not been very large. If you have ever taken a tour of a commoner's house that has been preserved in its original state since the 1700's or 1800's, you may have been struck by the uncomfortably low ceilings. You may have concluded, or have been told by a tour guide, that people were generally much shorter hundreds of years ago and didn't need high ceilings. However, this conclusion is misleading. Let's look at this subject more closely.