by eating
No. Flies don't recognise margarine as food, because it is an industrially-processed food, not natural food.
Flies are a source of food for frogs.
Flies and bees will both sit on uncovered food. Food should always be covered especially when outside in the elements.
It was developed because people saw flies gather around their food, and their food turn moldy. The explanation was that the flies and the mold came from the food. This was later proved incorrect because when their food was sealed off (with a lid), there weren't any bacteria or flies around their food.
Yes
flies
Flies use any dead animals as food.
flies survive by eating different types of food eg. nectar from flowers, germ infested food from rubbish bins :)
Flies vomit on the food to coat it in enzymes which then break it down. they then slurp the resultant gloop up with their modified proboscis.
Animals themselves are not flies, but flies can be vectors for food poisoning. Certain species of flies, like houseflies, can carry pathogens on their bodies and in their feces, contaminating food and surfaces. When these contaminated items are consumed, they can lead to foodborne illnesses in humans. Proper food handling and hygiene practices can help mitigate this risk.
Flies
Flies and insects.