There is a species of sea slugs that have mini-brains when they are young. They use them as they voyage through the seas looking for a perch from which they can sieve food.  But once they’ve found their perch, they no longer need such an expensive piece of equipment so…they eat their brains.
                                    From Origin Story; A Big History of Everything by David Christian
 

Museum curators are hoarders by nature. But spitballs? Really? At Harvard they've got drawers full of ancient spit wads. The wads of chewed up yucca (I kid you not, you couldn't make that up)are called quids. Scientists think this was prehistoric chewing gum--or more likely for toothaches, because yucca tastes, well--yucky. The real question is, who saves this stuff?  I thought I had trouble throwing things out… ​

​King Louis XVI’s magnificent palace at Versailles stood 12 miles west of Paris, but even palaces have their icky bit side, especially in the 1700’s. The private bathroom is a relatively modern convenience. Most residents of Versailles used chamber pots for nighttime nature calls. And in the morning servants tossed the contents out of the windows. The raining excrement led to a wise recommendation to always carry a leather umbrella when strolling around Versailles. Queen Marie Antoinette was splattered more than once. 
Princess d’Harcourt relieved herself in her skirts as she strolled along the palace corridors and courtyards trailing a mess for the servants to mop up.  One foreign visitor commented with disgust at the, “people laying their nastiness in such quantities that it was equally offensive to the sight and smell.”
The palace’s only flush toilets, or “English places” as they were called, were installed in the King’s and Queen’s chambers. The height of luxury, the bowls were crafted from porcelain and the seats from mahogany. Servants kept them spotless. So immaculate, in fact, that the King’s cat often curled into a ball and slept in the cool, clean bowl. Once Louis XVI sat down to take care of business without noticing the cat.  No sooner had the purpose of the King’s mission begun than the terrified cat attacked the King from below, sending him leaping into the air and charging through his chamber yanking bell pulls all the way.

​Maggots love to munch on rotting flesh. The fact that they don’t care for healthy tissue makes them great for healing wounds. Doctors in Caesar's army used maggots to clean gashes, often saving gangrenous limbs from amputation. Maggot use went out of favor with the discovery of penicillin (really? who wouldn’t want a maggot-infested wound? jam-packed with writhing wormy little buggers?). Today, maggots are enjoying a comeback. Antibiotic-resistant bacteria are no match for the slimy diseased-flesh eaters. In 2004, the U.S. Food and Drug Administration approved maggot therapy.