What is it about animals that lead fans of sports teams to believe they possess some sort of rallying power? That with a simple video of a monkey dancing on a screen, or an octopus sliding across the ice, a team will suddenly be empowered with a mystical momentum conjured from nothing?

Such is the power of St. Louis' rally squirrel, which appeared during an NLDS win over the Phillies. Ever since, it's been squirrel fever in St. Louis, and the furry rodent has even got its own MLB promo and T-shirt.

The rally squirrel is hardly the first animal to factor in a team's playoff pathos. It's not even the first "rally" mascot. But here's a look at all animals that have made their marks in the postseason.

Follow us on Facebook and Twitter to read them first!

Rally Monkey

Anaheim Angels: The 2000 season was a wild one for the Angels, and you could argue that it started with the Rally Monkey. The little jumper made his first appearance with the Angels trailing the San Francisco Giants in interleague play and developed a cult-like following. It continued in subsequent seasons and came into national prominence in 2002 when the Angels won the World Series against those same Giants.

Octopus

Detroit Red Wings: Red Wing fans have been chucking octopus on the ice since the 1952 playoffs, when local fish market owner Peter Cusimano winged one of his own. The eight legs were said to symbolically represent the eight wins it took to win the cup back then, and the tradition has stuck, despite many attempts by the NHL to end it.

Rat

Florida Panthers: During the 1995-96 NHL season, Florida winger Scott Mellanby used his stick to kill a rat that was scurrying around the Panthers locker room before a game. Mellanby went on to score two goals in the game, and goalie John Vanbiesbrouck coined the term "rat trick." It stuck through the Panthers' run to the Stanley Cup Final, during which fans showered the ice with thousands of plastic rats to celebrate goals. The NHL followed with an off-season rule the penalized home teams if fans disrupted games by throwing things on the ice.

Billy Goat

Chicago Cubs: Oh sure, the Curse of the Billy Goat isn't exactly welcome when the Cubs make the playoffs, but that goat is as present as any of the other animals on this list. When Billy Goat Tavern owner Billy Sianis and his goat were asked to leave a 1945 World Series game because the goat's odor, Sianis supposedly cursed the team. And now we're all cursed to hear about the goat anytime the Cubs make the playoffs.

Rally Squirrel

St. Louis Cardinals: And we're back to the critter that kick-started this list. You can't deny the power of the squirrel, whose Cardinals have marched all the way to the World Series since its appearance. Now we're just waiting to see what the Rangers come up with as a counter. Oh sure, they've got the "antlers" and "claw," but that's not quite the same. Here's hoping for an "Onslaught Armadillo" or something armadillo-related, at least.

Popular Videos On ThePostGame:
-- Adorable Jack Russell Learns To Play Catch With Himself
-- Kayaker's Controversial Swim With Blue Whale
-- Monkeys As Jockeys On Dogs