Walnut and mahogany were prevalent between the years 1700 to 1800, and maple and cherry were common from 1800–1900.
Oak enjoyed another 100 years of popularity from 1900 to the turn of the 21st century.
Some popular antiques are quite well documented and may be tied to a specific time period in history making an age determination quite simple. Adding to the complexity is the proliferation of copycat builders and modern furniture craftsmen who do an admirable job of cloning authentic antique furniture right down to the tool marks and date stamps.
While it is possible that an owner replaced the knobs on an antique with more modern units, you'll most likely be able to tell.
Tool marks and obvious signs of rough cuts are fairly typical with pieces more than 150 years old.
That said, it is important to realize that skilled craftsmen are building furniture by hand even today so you'll want to continue to investigate the age of the piece using at least one other method.
A single piece of antique furniture is more than a collection of nails, boards, and wood stain.
Antique furnishings can tell a story one that may only exist in the imagination of the lucky person acquiring the piece.