The 'Ecosystem' is very similar to the Proximity options. However, the ecosystem works integrated with other scatter systems. This can be super useful when you have a lot of scattering layers and you don't want them to overlap. For example, if you're creating a forest biome, you don't want foliage to grow inside the trees, or sometimes even near them. By using the ecosystem you can make sure that your foliage keeps a certain distance from the trees. Alternatively you can also use attraction to make certain things grow near others. Repulsion pushes away. Attraction, well, attracts.

⚠️ If the system selection menu shows options that aren’t a scatter system, you may have accidentally added an object in the ‘Scatter Systems’ collection. Simply move that object to a new collection.