Yes, Organisms compete for the resources they need to survive like food, air, water, space. In areas where these are sufficient, organisms live in comfortable co-existence, and in areas where resources are abundant, the ecosystem boasts high species richness (diversity).
All 3 of them explain the reason why people wear the mask to stop HIV
Pelican is the answer to your question
True examples of human disruption could be us cutting down trees in forests (deforestation) for wood or use in other things
