Please, admit this. We are gross. We like to turn everything beautiful into totally shitty, like literally. We can have a really nice dinner in a top restaurant of the town but next day we will pull out that dinner from our bottom in a stinky small room. Even you eat a $200 Turkish delight, you would turn that into some yucky colored mass next morning. And we hate that. We hate the poo. That is obvious I guess. And not only us, many other species share our concern. Disgust is one of the eight rasas of the Indian dance system called Natyashastra and is also a basic emotion according to Charles Darwin. This emotion recognized by wrinkling of the nose with a standard frown is universal across cultures. Disgust also lowers our blood pressure, reduce skin conductance and cause nausea. However doctors should prescribe med and not shit.
We are not the only species that try to stay away from exposure to excrement and there is a good reason for that. Our disgust response reduces the likelihood of ingesting diseases causing micro organism. Such organism can come many stuffs like decayed meat, vomit blood and of course poo. Disgust may reflect an intuitive understanding of microbiology. Even animals like cows, horses , reindeer like to stay away from poo. It is found that they cannot differentiate between parasitic and non-parasitic faces. So to avoid any disease they have “avoid all poo” rule
On the other hand some animals like the white footed wild mice would explicitly seek faeces. They like to play it dirty. The reason could be that the presence of faeces from other mice at the potential nesting location or near food suggests safety from predators. Infection from contaminated food is of lesser concern. Which is consistent to the fact that domesticated rodents which are generally at a much lowers risk from predators than their wild counterpart ,do avoid faeces like us
Perhaps, we human can afford to be disgusted by poo because we have no natural predators. We are indeed pretty lucky to have the luxury of not selecting which way we would like to die. Evolution have made us stay away from any kind of contamination which could kill us. So next time you get disgusted by public toilets think about the evolutionary science behind it and wash your hands for the sake of humanity.