Feces
[1][2] Feces contain a relatively small amount of metabolic waste products such as bacterially-altered bilirubin and dead epithelial cells from the lining of the gut.
The distinctive odor of feces is due to skatole, and thiols (sulfur-containing compounds), as well as amines and carboxylic acids.
[3][4] The perceived bad odor of feces has been hypothesized to be a deterrent for humans, as consuming or touching it may result in sickness or infection.
[8] This means that of all food eaten, a significant amount of energy remains for the decomposers of ecosystems.
Many organisms feed on feces, from bacteria to fungi to insects such as dung beetles, who can sense odors from long distances.
A combination of bile and bilirubin, which comes from dead red blood cells, gives feces the typical brown color.
[1][2] After the meconium, the first stool expelled, a newborn's feces contains only bile, which gives it a yellow-green color.
Breast feeding babies expel soft, pale yellowish, and not quite malodorous matter; but once the baby begins to eat, and the body starts expelling bilirubin from dead red blood cells, its matter acquires the familiar brown color.
[13] Animals such as the giant panda[14] and zebra[15] possess gut bacteria capable of producing biofuel.
The bacterium in question, Brocadia anammoxidans, can be used to synthesize the rocket fuel hydrazine.
They serve a valuable purpose in paleontology because they provide direct evidence of the predation and diet of extinct organisms.
Intact paleofeces of ancient people may be found in caves in arid climates and in other locations with suitable preservation conditions.
These are studied to determine the diet and health of the people who produced them through the analysis of seeds, small bones, and parasite eggs found inside.
To extract and analyze the information contained within, researchers generally have to freeze the feces and grind it up into powder for analysis.
[25] In Malaysia, tea is made from the droppings of stick insects fed on guava leaves.
Collected dog feces, known as "pure", "puer", or "pewer",[26] were mixed with water to form a substance known as "bate", because proteolytic enzymes in the dog feces helped to relax the fibrous structure of the hide before the final stages of tanning.
[28] Elephants, hippos, koalas and pandas are born with sterile intestines, and require bacteria obtained from eating the feces of their mothers to digest vegetation.
Many are euphemistic, colloquial, or both; some are profane (such as shit), whereas most belong chiefly to child-directed speech) or to crude humor (such as crap, dump, load and turd).
