By Chrös McDougall | Oct. 20, 2015, 2:10 p.m. (ET)
Top row (L-R) Gabby Douglas, Simone Biles, Aly Raisman; bottom row (L-R) Maggie Nichols, Brenna Dowell, Madison Kocian, MyKayla Skinner.

Any discussion of the U.S. women’s gymnastics team must start with Simone Biles, the reigning two-time world all-around champion.

But as a seven-woman squad heads to the FIG World Artistic Gymnastics Championships beginning this week in Glasgow, Scotland, it’s impossible to ignore Gabby Douglas and Aly Raisman, both double-gold medalists from the London 2012 Olympic Games.

And the other four team members — Brenna Dowell, Madison Kocian, Maggie Nichols and MyKayla Skinner — are hardly roster fillers. Kocian and Skinner helped Team USA win last year’s world team title, while Dowell and Nichols have strong résumés as well.

U.S. National Team Coordinator Martha Karolyi will have no shortage of tough decisions as she finalizes the six-person lineup and decides who will be the alternate.

No matter what Karolyi decides, however, the U.S. team will enter the competition as the favorite to cap off a half-decade of dominance of women’s team gymnastics: 2011 world champions, 2012 Olympic gold medalists and 2014 world champs (there was no team competition in the 2013 world championships). The usual suspects of China, Romania and Russia are expected to be Team USA’s biggest competition in Glasgow.

With less than one year out from the Rio de Janeiro 2016 Olympic Games, this year’s world championships inevitably are viewed as an Olympic preview. After all, the American women walked away with the 2011 world team title before running away with the 2012 Olympic team title. All four age-eligible gymnasts on the Olympic team were part of that worlds team.

If there’s one gymnast you can bet on seeing in Rio, it’s Biles, the favorite to win an unprecedented third world all-around title in Glasgow after three-peating as U.S. champion in August.

After that, though, write the names in pencil this time around.

In women’s gymnastics, young athletes tend to have an advantage.

As such, history shows that defending an individual Olympic gold medal will be hard for Douglas (all-around) and Raisman (floor exercise), but even making a second Olympic team is hard in this deep gymnastics country. In the six Olympic Games since 1992, only four of the 31 U.S. women’s gymnasts made more the one Games, with none doing so since 2000. And it’s not for a lack of trying. Five of the six 2008 U.S. Olympians began the 2012 season with hopes of making that year’s Olympic team. Three made it to Olympic Trials. None made it to London.

Age will be a factor not just for the Olympians, though. All seven worlds team members are at least 18 years old. Conversely, Raisman was the oldest member of the 2012 Olympic team at 18.

Meanwhile, promising young gymnasts such as U.S. junior champion Laurie Hernandez and Jazmyn Foberg would have at least merited consideration for this worlds team had they not fallen short of the 16-year-old age limit. But come next season, they’ll be seniors and eligible for the Olympic team — just as Kyla Ross debuted as a senior in 2012 and went on to make that year’s Olympic team.

History, of course, doesn’t have to be the rule, especially in a fickle sport such as gymnastics. Douglas and Raisman are already ahead of many of the 2008 Olympians who stagnated in their 2012 comebacks. And Biles is already setting her own precedents.

As the U.S. women first take the podium on Saturday for the qualifying rounds, here’s a look at the seven gymnasts and how they might factor.

At the world championships, each team has six gymnasts. Five compete in each event during the qualifying rounds with the top four scores counting; three compete and three scores count in each event for the team finals. Meanwhile, from qualifying, the top eight teams make the team final, and the top 24 all-arounders and top eight in each event move onto those finals, though only two per country can advance in each final.

Simone Biles
Age: 18
Hometown: Spring, Texas
How She Can Help: Considering she won 2014 world titles in balance beam and floor exercise while finishing second in vault — one year after medaling in all three events — while winning both all-around titles, the better question is where can’t she help?

Gabby Douglas
Age: 19
Hometown: Virginia Beach, Virginia
How She Can Help: The 2012 Olympic all-around champion showed some rust when she returned to competition this year, following a two-and-a-half year break. But she’s shown flashes of the gymnast who rose from unknown to Olympic champion in 2012. Strong in all four events, Douglas stands out on the uneven bars, typically the U.S. women’s weakest event.

Brenna Dowell
Age: 19
Hometown: Odessa, Missouri
How She Can Help: Long a top bridesmaid in the U.S. program, Dowell traveled to the 2013 world championships but didn’t make the cut to compete for Team USA and was the non-traveling alternate on the 2014 team. Should she make the cut in Glasgow, Dowell could help in floor exercise or uneven bars. The Oklahoma Sooner is taking a year off from college to continue her elite gymnastics career.

Madison Kocian
Age: 18
Hometown: Dallas
How She Can Help: An uneven bars star, Kocian won the U.S. title in the event this summer after finishing second in 2014. She represented Team USA in uneven bars during the team final at last year’s world championships.

MyKayla Skinner
Age: 18
Hometown: Gilbert, Arizona
How She Can Help: Undisputedly world class in two events, Skinner finished third in vault and fourth in floor exercise at last year’s world championships. Those routines will again be key in this year’s team competition. Yet with only two per country allowed in event finals, there could easily be a top-eight American who can’t compete for floor or vault gold.

Maggie Nichols
Age: 18
Hometown: Little Canada, Minnesota
How She Can Help: Though a rookie to the world stage, Nichols has shined at the U.S. championships. She moved up to second place in the all-around after finishing third last year (and missing worlds due to injury). While not dominant in any one event, Nichols was top-seven in balance beam, floor exercise and uneven bars in the last two U.S. championships.

Aly Raisman
Age: 21
Hometown: Needham, Massachusetts
How She Can Help: The rock of the 2012 U.S. Olympic Team won the gold medal in floor exercise and the bronze medal in balance beam. She remains one of the strongest U.S. gymnasts in both events, particularly floor exercise, where she upset two-time defending world champion Biles to claim the national title earlier this summer.

Chrös McDougall has been a reporter and editor for since 2009 on behalf of Red Line Editorial, Inc. He is based in Minneapolis-St. Paul.