Kelly Robinson looked into the weird practice of women jumping out of cakes:

• The Ancient Romans were the first known people to mix food with entertainment. They would cook and stuff one animal – such as a roasted pig – inside another, such as a cow.
• They also staged animals to make them look like they were alive. Fish swam in seas of sauce, and medievals continued this practice by using alcohol to create fire-breathing effects.
• This is also around the time that having an apple in the mouth of a pig became a thing. The idea was probably to make it look like the pig was alive and munching.
• By the end of the Middle Ages having living things – such as birds – inside food to fly out once the food was cut open, became popular.
• Having living people inside was a natural evolution and one banquet host managed to fit 28 musicians inside a pie.
• By the 1800s it was usually women in the pastries as such entertainment was often presented at parties by the elite for the elite. Wives, of course, were unwelcome.
• A 1970s article indicates that a cake jumper could make $220 (in 2015 dollars) per event.
• By the end of the 1970s having live humans come with your meal became less common as the equal rights movement meant that more and more women were at party events.
• The practice lives on though during events such as bachelor parties and areas of extravagant excess such as Las Vegas.

Read about the murder that truly brought the practice into the mainstream, the role that The Sims played, and famous examples of humans jumping out of food over here.

Source: Today I Found Out