- On or near food: Many flies, such as house flies and fruit flies, lay their eggs on or near food sources. This is because the larvae that hatch from the eggs will feed on the food.
- In moist areas: Some flies, such as mosquitoes and black flies, lay their eggs in moist areas, such as near water or in damp soil. This is because the larvae that hatch from the eggs need moisture to survive.
- On animals: Some flies, such as botflies and horseflies, lay their eggs on animals. This is because the larvae that hatch from the eggs will feed on the animal's blood or tissue.
- In other protected areas: Some flies, such as blow flies and flesh flies, lay their eggs in other protected areas, such as under leaves or in cracks in wood. This is because the larvae that hatch from the eggs need a protected environment to survive.
The specific location where a fly lays its eggs is often determined by the fly's instinctual behavior and the type of environment that is most suitable for its larvae.