Then and Now: What has changed in MMA since 2005?

A long term dynamic develops in every sport that sticks around for a while. A section of the fan base will inevitably compare the play of today to their heroes from yesteryear.  Whether it is the baseball fan that longs for the day where they didn’t have to worry about someone using performance enhancing drugs after every home run, or the football fan that yearns for the era of hard hitting and less complaining in the NFL. One thing is a common factor; this group wishes things would go back to

The Greatest Champions of the Sport.

The sport of Mixed Martial Arts has seen many great fighters and champions come and go, but only a few have cemented a legacy for the ages. I have selected five fighters, from their own respective divisions, that have not only claimed a title but shaped the sport as well. I did not add the Featherweight or the Bantamweight divisions due to the fact that most casual fans are not aware of their existence, and the divisions are relativity new compared to the five major weight divisions.
Heavyweight: