'Dancing With the Stars': Which stars (and not-quite-stars) will participate in season 21?

'Dancing With the Stars' debuts later this month, with a full lineup of reality TV stars, singers, and sports figures,

We now know the full list of celebrities participating in this season of “Dancing With the Stars.”

Actor Gary Busey, former Backstreet Boys singer Nick Carter, and chef Paula Deen will all take to the dance floor for the 21st season of ABC’s reality competition. Joining them will be Alek Skarlatos, an Army National Guard specialist who very recently helped stop an attack on a Belgian train; jockey Victor Espinoza, who recently earned the Triple Crown with horse American Pharaoh; “Honey, I’m Good” singer Andy Grammer; and Bindi Irwin, a conservationist who is also the daughter of Steve Irwin. 

Singer Chaka Khan, Vine star Hayes Grier, and singer and “Braxton Family Values” star Tamar Braxton will also be participating along with “Spy Kids” star Alexa PenaVega and her husband, “Big Time Rush” actor Carlos PenaVega. “Real Housewives of Atlanta” star Kim Zolciak Biermann will be competing on the show as well.

Pros Tony Dovolani, Valentin Chmerkovskiy, Sharna Burgess, Anna Trebunskaya, Louis van Amstel, Karina Smirnoff, Emma Slater, Allison Holker, Keo Motsepe, Derek Hough, Mark Ballas, Lindsey Arnold, and Witney Carson will partner the stars this season.

Actress Rumer Willis triumphed with Mr. Chmerkovskiy last season.

As “Dancing” has continued, certain kinds of contestants pop up frequently. Football players have often competed on the show and have often done well, with players such as Donald Driver of the Green Bay Packers taking the crown in the past. Other sports figures like gymnasts and ice dancers have also competed, with ice dancer Meryl Davis recently winning. This year, jockey Espinoza represents the sports world.

The show has seen its share of reality stars as well. Chris Soules, who appeared on ABC’s reality show ‘The Bachelor,” competed on the previous season of “Dancing,” and Sadie Robertson of “Duck Dynasty,” Jack Osbourne of “The Osbournes,” Kate Gosselin of “Jon and Kate Plus 8,” and Nicole Polizzi (better known as “Snooki”) of “Jersey Shore” have all appeared on recent seasons as well. This season, Ms. Biermann and Ms. Braxton come to “Dancing” from a reality show background.

Singers have often been part of the “Dancing” celebrity lineup as well. Last year, singer Patti LaBelle participated, as have Christina Milian, Kellie Pickler, and Joey Fatone. This year's songsters are Mr. Carter and Mr. Grammer.

Vine star Mr. Grier highlights the producers' efforts to bring in people who have found fame online, such as recent dancer Bethany Mota, a YouTube personality. Fox made a similar push for the Teen Choice Awards, which now include several categories for “Web star” such as comedy and best user of Vine. 

Another group of not-quite-celebrities who frequently appear on “Dancing” are military heroes or other inspirational figures. Last year, former soldier and amputee Noah Galloway participated on the show, as have Paralympian Amy Purdy and actress Valerie Harper, who had been diagnosed with cancer.

The variety of contestants who appear on the show reflect the tastes of viewers. The sheer number of entertainment genres in which the personalities appear – sports, music, TV, movies, even online entertainment – show how many forms of entertainment are available to the public. The choice to include reality stars and "Bachelor" contestants also hints at the networks' love of synergy – that is, bringing viewers from one show to another. And who doesn't love narratives of heroes triumphing over adversity?

The new season of “Dancing” is approaching quickly – the first episode airs on Sept. 14.