When thinking about reality show hosts, there are really only a handful of names that immediately come to mind as the most prominent among them: Ryan Seacrest, Jeff Probst, Phil Keoghan, Nick Cannon, Tom Bergeron, Chris Harrison, and even Temptation Island's Mark L. Walberg are some of the best-known names.
Many other personalities have taken on hosting gigs as well, and some have been short-lived. In some cases, it wasn't that the person was fired from the gig, but they might have simply decided to move on. Or, they were just one in a rotating list of many hosts.
Often times with reality shows, it's not one but two co-hosts who help lead and narrate the series. They might have, in that instance, left together. But that isn't always the case.
Brian Dunkleman: American Idol
Dunkleman has sadly become known as being the co-host who didn't think American Idol would amount to much and decided to leave the show after season one. He ended up not getting replaced at all, as it was clear that Ryan Seacrest could hold down the fort on his own. Idol became a roaring success, launching the careers of some of today's biggest superstars, like Kelly Clarkson, Carrie Underwood, and Jennifer Hudson.
Seacrest, meanwhile, has gone on to become a massive success in virtually every area of the entertainment business. For his part, Dunkleman has expressed that he didn't feel he did a good enough job and didn't get along well with Seacrest. So, he wasn't confident he would have been asked back anyway.
Regis Philbin: America's Got Talent
The late Regis Philbin was one of the best and most versatile television hosts of this generation, having done everything from talk shows to game shows, and even the first season of this mega-hit reality competition series.
He hosted season one of America's Got Talent back in 2006 but flying back and forth between Los Angeles and New York City where he was filming Live with Regis and Kelly at the same time became too much. He was replaced in 2007 by Jerry Springer, who served as host for the following two seasons, after which Nick Cannon took over through to season 11. Tyra Banks was host for seasons 12 and 13 and was replaced by Terry Crews, who remains the current host.
Fred Willard: Market Warriors
Very similar to Antiques Roadshow and produced by the same company with the same appraisers participating, this show saw professional antiquers buy items from the flea market on a budget then resell them at auction.
The late Fred Willard was the original host of the PBS series in 2012 but was actually replaced halfway through the season by Mark L. Walberg due to Willard's arrest for allegedly engaging in a lewd act in a movie theater. Walberg re-voiced parts of the show Willard had already done, and the series only lasted a single season.
Dan Levy And Julia Chan: The Great Canadian Baking Show
Fans know Dan Levy as David from smash Emmy-winning hit series Schitt's Creek, as well as the son of actor Eugene Levy. They also know that he is Canadian. But what many fans might not know is that he was co-host for not just the first, but also the second season of the Canadian version of The Great British Bake-off.
He co-hosted with Julia Chan, known from the Canadian medical drama Saving Hope. The pair could not continue for season three due to scheduling conflicts and were replaced by Aurora Browne and Carolyn Taylor from the Baroness von Sketch Show for season three. Season four is hosted by Ann Pornel and Alan Shane Lewis, both comedians and Second City alumni.
Anderson Cooper: The Mole
News reporter Anderson Cooper took the gig as host of this reality competition series, one of many from the past that fans think should be rebooted. He served for the first two seasons after being replaced by Ahmad Rashad. The series ended with Jon Kelley as host.
The idea of the show was to make players complete missions to collect money for a pot that will eventually go to one winner. But one person is a secret "mole" who must focus on sabotaging the efforts of the team. By the end of each episode, the players are given a quiz and the person who has the least amount of knowledge about the mole is sent home.
Blair Herter & Alison Haislip: American Ninja Warrior
It's tough to imagine American Ninja Warrior without the play-by-play commentary by the enthusiastic and passionate long-time hosts, Matt Iseman and Akbar Gbaja-Biamila. But they weren't the original hosts of the series.
When American Ninja Warrior premiered in 2009, it was hosted by Blair Herter and Alison Haislip from G4. Iseman took over for Herter in season two and MMA fighter Jimmy Smith was brought on board, while Haislip was relegated to a sideline reporter position. Smith was later replaced by Olympic medalist Jonny Moseley and Angela Sun, a sportscaster, took over for Haislip. Gbaja-Biamila didn't join Iseman until season 5 while the sideline reporter gig was taken over by Jenn Brown that same year. Iseman and Gbaja-Biamili proved to be the dream team as they continue to host to this day. Meanwhile, the sideline reporter job has been done by Kristine Leahy and then Zuri Hall.
Nicole Scherzinger & Steve Jones: The X Factor
When Simon Cowell brought his popular British series The X Factor to America, it needed a few big names attached to it to make a splash. Alongside Cowell, Paula Abdul, Cheryl Cole, and L.A. Reid were judges of the first season while Nicole Scherzinger and Steve Jones were co-hosts. Before the season was over, however, Scherzinger stepped down from her co-hosting role and replaced Cole on the judging panel. Demi Lovato replaced Abdul and Britney Spears replaced Scherzinger in season two as judges.
For season two, Khloe Kardashian and Mario Lopez became the new co-hosts, and for the third season, Lopez hosted on his own.
Eric Nies And Mark Long: The Challenge
This long-running reality competition series technically did not have a host at all for its first season. Rather, a former cast member would perform host-like duties. The Real World New York's Eric Nies and Road Rules' Mark Long took over in season two, but that was the first and last time they appeared.
Freestyle skier Jonny Moseley and BMX rider Dave Mirra took over for a few seasons before the regular host T.J. Lavin came on in season 11. Now in its 36 season, Lavin continues to host The Challenge.