Traditionally when a bird poops on you that's a sign of good luck. While it might sound strange to some, Catalonia an autonomous community of Spain, has taken this tradition to a whole other level, involving 18th Century customs that involve poo. Like the bird poop theory, Catalonians see poo "as a sign of good luck as it fertilizes the earth and ensures a good harvest for the coming year."

According to Barcelona -- Metropolitan, the "The Caganer" and the "Caga Tió" are two beloved Catalonian traditions. While they might make us laugh and be silly, it's interesting to learn the history of these Christmas traditions.

THE CAGANER

"The caganer is a small, defecating figure associated with Christmas. The caganer is a tradition not only in Catalunya but also in other areas of Spain, Italy and Portugal. The typical Catalan caganer is squatting with his trousers around his ankles; he wears a red barretina and is often reading a newspaper or smoking a pipe.

"The tradition of the caganer is believed to be 300 years old. An Iberian votive offering which depicts a holy warrior excreting has been discovered near Tornabous in the Urgell and can be dated back to the early 18th century. Originally, the caganer was a necessary figure in the nativity scene. He was thought to bring good luck and happiness to the family and his fecal droppings were a symbol of wealth and the promise of a productive new year.

"The caganer today is still often placed within the Catalan nativity scene. Local nativity scenes generally depict the entire town of Bethlehem and the caganer is usually found squatting in an obscure corner.

"The caganer is said to be one of the most popular figures in the Catalan nativity scene. In December 2010, a 19-Foot, 8.22-Inch caganer was placed in the Maremagnum Shopping Centre. This gargantuan figure grabbed the Guinness World Record for Largest Caganer."

According to TIME, "reasons for his existence vary. The BBC has done some serious digging with one local in Barcelona explaining that, "It's typical of Catalonia. Each house buys one for Christmas, I don't know why (we do it), it's just a tradition."

TIME found Joan Lliteras, a "caganer connoisseur," who owns a collection of some 600 caganers as well as being the founder of an association, explained the tradition in more detail.

"There was the legend that if a countryside man did not put a caganer in the nativity scene, he would have a very bad year collecting vegetables," he said, claiming that the figurine is a symbol of fertility and good fortune. "The caganer is never in the front of the nativity scene. That would be a lack of respect. He's always hidden in a corner, under a bridge or behind a tree and every morning the children play a game, hunting for the caganer."

Caganers have become a booming business with an "inevitable celebrity spin-off," TIME points out. Christmas markets sell the likes of politicians, soccer players, foreign presidents, rock stars and royalty. There's one of the Queen of England and another of Presiden Obama, among many others.

THE CAGA TIÓ

"Caga Tió is a much-loved Catalan tradition used to celebrate the Christmas season. It's a log which is often given human physical features, such as eyes, eyebrows, legs and a nose. It's wrapped in a blanket for warmth and is crowned with the traditional Catalan barretina. The whole family customarily comes together before the beginning of the Christmas season in order to create the Caga Tió.

"Caga Tió is cared for by Catalan children in the weeks leading up to Christmas. From December 8th his behind is wrapped in a blanket and he's fed orange peel and turrón (a type of Spanish nougat) every evening. It's thought that the more the Caga Tió is fed, the more presents or Christmas goodies he'll excrete from his behind come Christmas day.

"El Tió needs some persuasion to drop his load on Christmas day and the children of the household are given sticks in order to beat him into delivering his many and various festive offerings. While beating the Caga Tió, Catalan children traditionally sing a song -- the words may vary from town to town but the tune stays the same. A typical version goes like this: 'Caga tió, caga torró, avellanes i mató, si no cagues bé et daré un cop de bastó. Caga tió!' This translates literally as: 'Sh*t log, sh*t turron, hazelnuts and cottage cheese, if you don't sh*t well, I'll hit you with a stick. Sh*t log

Catalonia is an autonomous community of Spain, designated a "nationality" by its Statute of Autonomy. Catalonia comprises four provinces: Barcelona, Girona, Lleida, and Tarragona. The capital and largest city is Barcelona, the second largest city in Spain, and the center of one of the largest metropolitan areas in Europe. It borders France and Andorra to the north, the Mediterranean Sea to the east, and the Spanish regions of Aragon and the Valencian Community to west and south respectively. The official languages are Catalan, Spanish and Aranese (an Occitan dialect).

Catalonia, which is one of Spain's most developed regions with a population of 7.5 million, has been fighting to be an independent state from Spain. 

According to the BBC, the Catalan Government has set a date for when it plans to hold a vote in Catalonia with two questions, the second of which implies, if a majority of people vote "yes", that Catalonia would no longer be part of Spain.

"However, the Spanish Popular Party led-government, as well as the main opposition Socialist Party have already said this can not happen," the BBC reports. "Catalan pro-independence parties, which hold a majority of parliamentary seats in Catalonia, still sound determined to hold the vote, come what may."