primarily what do mushrooms eat? specific examples would be appreciated also.
Mushrooms are the fruiting bodies of certain fungi. The fungus that puts forth the fruiting body (i.e. the mushroom) consists of mycelium, which is basically a fungal growth within a medium that the fungus feeds on. That can be something like leaf litter, compost, tree bark, whatever the particular fungus prefers. Thus, certain mushrooms are apt to be found under conifers, for instance. I have mushrooms growing at the edge of my backyard compost pile. I have a suspicion of the species but I would not eat it without a positive identification, but I haven't bothered. I have a nice big book that's really good for identifying mushroom species (
Mushrooms Demystified). I used to go into the hills here and collect mushrooms after the rains, bring them home and identify them. It's fun. They are so varied and often quite beautiful.
The mushroom itself, being a fruiting body, produces spores, which are like tiny microscopic seeds that fall from the underside of the mushroom (in most species) and float in the air and settle eventually. If one of those spores settles in a place conducive to the fungus growing, a new area of mycelium is formed and if conditions are right, more mushrooms are produced. Such is the life cycle of these fungi.
As explained previously in this thread, mushroom mycelium can form symbiotic relationships with other plant species.
Yes,
Psilocybe cubensis, a famous and rather large psychedelic mushroom does grow out of cow-pies.