Back in the mid-1980s, when Bill Parcells was head coach of the New York Giants, his Friday press conferences provided an education for beat reporters that covered the team. There were no television cameras, no radio microphones -- just familiar faces and informed conversation.

Parcells would offer insights on topics ranging from John Madden's football knowledge, Bill Walsh's intuitive offenses and, on several occasions, the virtues of the Samoan football player.

Samoans were built, Parcells generalized in his politically incorrect way, along the lines of his favorite football build -- big and boxy. In a word: squat. Physically, they were the perfect players for the trenches. Mentally, they were as tough as it got in the NFL, he insisted. Many in the league agree -- on and off the record.

"Certainly they have those characteristics," Indianapolis Colts president Bill Polian said. "Those I've seen play ball have the perfect physique. As a class of people in the NFL, they are exceptionally tough and exceptionally good athletes for their size."

In his book "Taboo: Why Black Athletes Dominate Sports and Why We Are Afraid to talk About It," published in 2000, author Jon Entine tackles the emotionally charged subject of genetic variation.

In it, he wrote: "Polynesians, especially the Samoans, are amongst the world's most mesomorphic (muscular) body types. A number of studies have shown that muscle bulk and the degree of muscularity, especially in the thigh and buttock, are important predictors of success in rugby players, whereas the opposite applies in such sports as distance running. This genetic admixture helps in part explain why athletes from this region are large, agile and fast."

The development of muscles in the thigh and buttocks area is very useful on the NFL field, particularly along the line of scrimmage, where strength, leverage and balance are important factors. It is worth noting that 21 of those 28 Samoans in the NFL play along the offensive or defensive line. Their strength, essentially, is their strength.

Dr. Kenneth Kidd, professor of genetics and psychiatry at Yale School of Medicine, studies genetic variation. He warned that stereotyping is dangerous, but allowed that different populations have slightly different body types.

"East African herders are generally tall and thin with long legs. It's not surprising that marathon runners come from there," Kidd explained. "The Japanese tend to have longer torsos and shorter legs. In a sense, that makes it easier to succeed as a Sumo wrestler.

"Not everybody in these populations is like that, but there is a tendency for a higher proportion of the population to be like that. That has underpinnings in terms of small genetic differences. The importance is in the small differences."

Kidd said that a number of Polynesians struggle with obesity, which suggests a different gene pool. And that difference, he added, is accentuated by the remoteness of the South Pacific islands.

"Polynesians in general have a reduced amount of genetic variation," Kidd said. "They are more homogeneous than, say, a European population because of their isolation."

Manu Tuiasosopo is not a geneticist, but he had a few ideas on the subject. He played in the league for eight seasons, and his son, Marques, is a backup quarterback heading into his second season with the Oakland Raiders.

"There's the high-protein diet," Manu Tuiasosopo said. "There's a lot of tuna, chicken, corned beef and then we have green bananas and taro root, which is sort of like a potato. Of course, now there's a McDonald's on the island -- the kids will probably start eating Happy Meals."

For Marques Tuiasosopo, the Samoan success is more related to an unwavering mindset.

"There's an attitude in our culture," he said. "I go back and look at pictures of great-great grandparents and they were wearing ceremonial clothes. They battled other cultures and maybe that's been passed down through the years.

	“	... In general, they're quiet, don't like to bring attention to themselves. But get into a competitive situation and it's like Jekyll and Hyde -- it's fierce. My dad would pat his chest and say, 'Son, you have to have a big heart and lay it on the line.' ”
		— Marques Tuiasosopo

"It's in the blood, an attitude when they go out there. Off the field -- I can't speak for a particular person -- but in general, they're quiet, don't like to bring attention to themselves. But get into a competitive situation and it's like Jekyll and Hyde -- it's fierce. My dad would pat his chest and say, 'Son, you have to have a big heart and lay it on the line.' "

And what of the dearth of skill-position players? Only nine of the 28 players -- three linebackers, two tights ends, two fullbacks, one halfback and one quarterback -- play the so-called "skill positions."

University of Hawaii coach June Jones has said he needs to visit the mainland for athletes who play off the line of scrimmage, but generally can stock both sides of the line with players from the surrounding islands. Is there a cultural bias against Samoans as there was once against African-Americans?

"I don't see that," Tuiasosopo said, referencing Jack Thompson and, of course, his son Marques. "The standards are being raised each year -- bigger, faster, stronger -- and these kids have every opportunity to succeed."

Greg Garber is a senior writer for ESPN.com