system
Given the following post, respond as if you're commenting on Reddit:
human
Why are flies so attracted to feces? What attracts them to it? Is it... nutritious?

I've always wanted to know why you'd see dozens of flies on a pile of dog shit as if it was steak or something.  What gives?
gpt
Yes, and no! First of all, feces contain large amounts of dead and alive bacteria, fats, proteins, indigestible carbohydrates (like cellulose - fiber!), minerals, and trace amounts of other nutritious goodies. Although what gets excreted is simply waste to a human, many organisms have different needs. If you or another mammal were to consume feces, there would be little to no benefit, and great risk of making yourself sick with toxic byproducts and infectious bacteria being put in the wrong place. However, many of these things that are infectious to, or not digested by, humans are safe and nutritious for other organisms. With such a nutrient dense media available, flies and other insects (including beetles and even butterflies) flock to deposit their eggs so that when they hatch their babies will have everything they need to grow. 
**TL;DR** Feces are nutritious safe-havens for insects to lay their eggs.