Those seeking proof of the famous biologist's theory on adaptation or survival of the fittest need look no further than the petri dish that is SEC football.
With seven of 12 schools replacing starting quarterbacks, offenses in the SEC are undergoing a shift toward the running game rarely seen in the 12 years since the conference expanded by adding Arkansas and South Carolina in 1992.
The percentage of total offense from the pass was an even 50-50 split with rushing in 1992 before passing rose to 55 percent in 1994.
The percent of offensive yards from the pass has been 58 percent or greater every year but one since 1994 and was 60 percent or greater from 1997-2001, reaching a high of 63.5 in 1999.
The two teams bucking this ground trend in 2004 have been setting the rushing standard for years and meet this Saturday on the Plains when Arkansas (3-2, 2-2 in SEC) visits No. 4 Auburn (6-0, 3-0).
Arkansas led the SEC the last two years in rushing with a 62-38 percentage split in 2002 and a 56-44 difference in favor of the rush last year while Auburn was close to even at 49 rush, 51 pass in 2003.
This year, Arkansas and Auburn have both shifted to 55 percent pass, 45 rush and now sit atop the conference's offensive categories.
After its 22-point swing from the run to the pass and with 10 new starters, Arkansas leads in both total offense (459.2 yards per game) and scoring (37.8 points per game) with Auburn ranked next at 435.2 and 33.8.
But as a whole across the SEC in 2004, rushing attempts and yards are up while passing attempts and yards are down.
Teams attempted an average of 38 runs and 30 passes per game in 2003 with 58 percent of their yards coming from the pass and 42 from the run.
Through seven weeks of play, SEC offenses are now attempting 40 runs per game to 28 passes.
The yardage ratio has narrowed back to 55-45, the closest the gap has been since the 2002 and 1994 seasons.
"I do think there is a trend back toward running the football and the physical approach to the game," said South Carolina coach Lou Holtz, whose Gamecocks have an SEC-leading 273 rushing attempts but are sixth in rushing yards with 993 (3.9 per attempt).
The SEC has four teams -- Alabama (13), Arkansas (16), Tennessee (17) and Auburn (21) -- ranked as top-21 rushing offenses in the country, easily the most since the conference expanded.
Conversely, the SEC has no teams in the top 20 in passing for the first time over the same period.
Tennessee, Ole Miss, Mississippi State, South Carolina and LSU have rotated quarterbacks who more than ever are rushing threats.
Three teams have their quarterback as their leading or second-leading rusher and five have their QBs among their top-five rushers.
Is the adaptation working?
Look no further than last weekend when Tennessee (4-1, 2-1) went on the road to then-No. 3 Georgia, got 107 yards from Gerald Riggs and freshman Erik Ainge outplayed four-year starter David Greene at quarterback to lead a 19-14 win.
Ole Miss used three quarterbacks on its first three plays and eventually won at South Carolina helped by 97 yards rushing from Vashon Pearson and Ethan Flatt throwing for 217 yards plus the game-winning touchdown after being the third quarterback to take the field.
LSU (4-2, 2-2) started JaMarcus Russell and brought Marcus Randall off the bench to lead the comeback win at then-No. 12 Florida. Joseph Addai rushed for 93 yards while Randall threw for 199 and rushed for 46, hitting Addai for the game-winning touchdown.
Tennessee is leading the Eastern Division with wins against Florida and Georgia, South Carolina (4-2, 2-2) is on the cusp of bowl eligibility yet again and Ole Miss (3-3, 2-1) has rebounded from a 1-2 start to hold the second spot in the West.
SEC offenses have absorbed the quarterback losses with an abundance of talent at running back a year after Casey Clausen (Tennessee), Jared Lorenzen (Kentucky) and Eli Manning (Ole Miss) departed the quarterback ranks, taking 30,180 yards and 234 touchdowns with them.
Florida coach Ron Zook, who has the SEC's most balanced attack with 172 rushes and 173 passes, said it's natural selection for coaches to adapt their offenses based on personnel and experience.
"I think coaches are going to do what gives them the best opportunity to win," Zook said. "I'm sure it's just kind of worked out where teams feel like running the football gives them a little better opportunity to win."
OFF AND RUNNING
A great example of adaptation was the national champion Tennessee team of 1998.
A year after losing Peyton Manning, Tennessee went from 3,981 passing yards to 2,250 with Tee Martin during its title season.
Tennessee went from 1,813 rushing yards to 2,536 -- a 53-47 rush advantage -- led by the duo of current pros Jamal Lewis and Travis Henry. Martin also was a mobile threat and helped the Vols survive several close calls and finish the perfect season even Manning couldn't accomplish.
Just like in 1998, the Vols have changed gears quickly this season after losing Clausen. Tennessee has gone from a 138-yard rushing average last year to 204 led by tailbacks Riggs (80.6 ypg) and Cedric Houston (78.6).
Auburn, Arkansas, LSU and Ole Miss have also successfully rotated running backs this season.
Mississippi State coach Sylvester Croom may be taking lumps in his first season, but he knows a thing or two about running the ball after coaching Barry Sanders at Detroit and Ahman Green at Green Bay.
He said running the ball successfully is the easiest solution for a young quarterback or an inexperienced offense.
"It takes the pressure off him if you can run the football," Croom said. "It speeds the game up. It hopefully wears on teams, particularly if you've got a runner who not only can move the chains but who, when he gets out in the open, can score touchdowns.
"You have a chance to score points and still be safe. There's fewer bad things that can happen when you run as opposed to when you throw it."
And, as Arkansas senior quarterback Matt Jones demonstrated as a freshman in 2001, a running threat at quarterback can be the great equalizer for a stagnating offense.
"It creates a tremendous problem for the defense because the one guy you don't account for in coverage is the quarterback," Croom said. "If he pulls it down and runs, he has a tremendous chance of making a positive play."
Jones leads Arkansas with 313 rushing yards and South Carolina's second-leading rusher is quarterback Syvelle Newton, who has rushed for 177 yards and 4 touchdowns on 62 carries.
Ole Miss has used Robert Lane and Michael Spurlock as its running quarterbacks, Shane Boyd is Kentucky's second-leading rusher and Tennessee has done the same with Brent Schaeffer.
"You have to do what your quarterback's best talents are suited for," Holtz said.
ONE AND THREE
Arkansas was dead-last in passing a year ago (189.4 ypg) and Auburn was just two spots better (192.2).
All of a sudden, Arkansas is leading the conference with 253.2 passing yards per game while Auburn is third (237.2) in the first year of the West Coast offense led by senior Jason Campbell.
Razorbacks coach Houston Nutt and Auburn coach Tommy Tuberville were tired of defenses loading up against their run-oriented offenses and knew changes had to be made.
"I think both teams have seen a lot of eight-man fronts in this league, people trying to stack the box up and that creates better passing lanes and a chance to get the ball down the field," Tuberville said. "I know that's been our forte so far. We've been able to make plays, where last year we didn't."
Nutt echoed that thought and said Jones' maturation as a senior -- like Campbell's -- has had a lot to do with the Razorbacks' expanded passing attack.
"People tend to overpopulate the line of scrimmage with us," Nutt said. "That creates one-on-ones. Matt's gotten better seeing the field, he made a big commitment to throwing the ball all summer and he's more accurate. The offensive line is improving and protecting better than we thought we'd be at this time."
Though Arkansas and Auburn have improved in the pass, they've hardly abandoned the run.
Arkansas is second in SEC rushing (206 ypg) and Auburn is fourth (198.0).
"It still takes a good running game to win this league, to be able to have balance," Nutt said. "And you strive for that.
"This league makes it tough because they try to make you play left-handed."
Arkansas and Auburn have shown an ambidextrous offense is the best adaptation of all.
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