#1. Why is our poop brown in color?
Our poop (stool, or dung) is brown color mostly comes from bilirubin, formed by the breakdown of dead red blood cells, which our bodies try to get rid of as waste.
As you may notice our stool may not be brown all the time. For example, green stool can result from rapid transit of feces through the intestines, as in diarrhea. The color can also come from pigments, like a blue-color ice-cream or red chili.
If we get black stool, we have to be careful, because it indicates digested blood in the stool and thus a possible problem in the intestines.
We may be able to find seeds, nuts, corn and beans in the stools as well! These goods have high fiber content and remains undigested.
#2. Why does my stool smell so bad?
Stool stinks because the bacteria that help digest our food produce smelly organic compounds rich in sulfur and nitrogen, same compounds that give fart its "unique" odor.
Meat is richer in sulfides, so yeah, that's probably why your dad's fart is smellier. That's why dogs and cats poop are also smellier than those of cows and goats.