When Mixed Martial Arts first started it was truly a style-against-style competition. Royce Gracie helped create the UFC in 1993 to pit his Brazilian Jiu-Jitsu against other martial artists and he was able to do just that.
MMA in its early phase featured fighter who only had one style of fighting and it provided a fairly pure martial art vs martial art contest.
Wrestlers were quick to join the mixed and together with submission grapplers the ground fighters dominated the strikers, but the first evolution of MMA would even the playing field.
Fighters began to expand their skill sets to help maximize their strengths. Strikers began to master the sprawl to help keep the fights standing and learn how to use the guard to protect themselves once on the ground.
Chuck Liddell burst on to the scene as an explosive puncher, but his legendary sprawl is what allowed him to become such a transcendent fighter. Wanderlei Silva earned a black belt in Brazilian Jiu-Jitsu but he only ever recorded one submission victory, so it seems clear the grappling was a path back to his feet to help use his outstanding Muay-Thai.
This allowed strikers to keep ground fighters standing until they were able to knock them out.
Ground fighters responded by working on their own striking. Randy Couture worked on his 'dirty boxing' and turned himself into one of the smartest fighters on his feet. Tito Ortiz worked hard on his boxing and ended his UFC career (maybe) with very good hands to go with his acclaimed ground skills.
While fighters were widening their skills sets, it was never more than a dabbling to maximize their primary skill set. And basically the styles can be broken into three basic groups.
Any martial art using the hands, feet, elbows, and knees to strike their opponent, it includes but is not confided to Boxing, Muay Thai, San Shou, Taekwondo and many other. It gives a fighters the ability to keep fighters at a distance, do serious damage and fight ending blows. All these techniques are rendered useless on the ground.
Ground fighting styles focused on take-downs and top position, including Grecco-Roman Wrestling, Steppe Wrestling, Grecco Wrestling and many others. It gives a fighter the ability to take the fight the ground with take-downs or keep the fight standing with sprawls.
While superb on the ground, wrestlers are very focused on staying off their back and will often panic if put on their back.
Ground fighting focused on the use of leverage, position, and locks to force a fighter to submit. Most chokes and joint locks have their roots in these disciplines. Brazilian Jiu-Jitsu is the most popular form but Sambo and Judo are also common.
These fighters are excellent on the ground, very comfortable on their backs, both able to defend themselves and go on offense. They tend to be less aggressive with take-downs and will often wait till their opponent to take them down.
MMA fighters were becoming more well rounded but the next step forward was about to be made and three fighters would emerge has the heralds of this next step.
B.J. Penn, Anderson Silva, and Georges St. Pierre all made their professional debuts in the early 2000s and from the start it was clear these were different kinds of fighters. They entered in with an outstanding grounding in one skill: B.J. was a BJJ prodigy, Anderson Silva was a Muay Thai ace, and GSP had a stroke Karate, BJJ, and Wrestling background.
These three added to their skill sets, but these were no mere secondary skills in their competitive natures they set out to master a whole new set of skills.
B.J. Penn has become an excellent boxer and has been able to out strike fighters in addition to dominate them on the ground. Anderson Silva earned a black belt in BJJ and has been very keen to show off his excellent ground skills submitting two excellent ground fighters in Travis Luther and Dan Henderson.
Both fighters have progressed their skills to dominate fights both on their feet and on the mat.
Georges St. Pierre represents the final step forward in this progression, athletic doesn't describe St. Pierre any more because it entails an undeveloped talent. His skills are now fully developed and he represents the new MMA fighter.
It is not enough to be excellent at one of the styles, to be a dominating fighter in modern MMA one must be outstanding at striking and at least one ground skill. Penn and Silva both have added one elite skill, Silva BJJ and Penn boxing.
But in St. Pierre's case he has practiced karate and boxing from a very young, he has a black belt in BJJ and has some of the best wrestling skills in the sport.
These three fighters represent the shift in MMA towards these dual-master fighters, new fighters have followed them in a similar mold including names like Lyoto Machida, Miguel Torres, Gegard Mousasi, Anthony Johnson and others all have come forward with a dual set of skills, both ground and standing.
It is the natural progression of the sport and it bodes an exciting and fast paced future in MMA matching true mixed martial artists against each other.