Answer:
Competition for food happens when there is a limited amount of food resources available. The members of a species that eat that food who are best adapted to access the food are more likely to reproduce and pass on their genes to the next generation.
For example, we have a bird feeder with a narrow opening for food. The small-headed birds can reach the food, the bigger-headed birds cannot. If this was the only food source for this area, then over time, there would be more smaller-headed birds than large-headed birds, due to the competition for food and success/lack of success.
Yes, I do think so. I believe the rain can break up the soil depending on the type of soil as well as rain amounts. If it doesn't rain much in California their soil might be dry and brittle, but id it rains in South Carolina theirs might by softer and moist.
All organisms have the ability to maintain homeostasis.