system
Given the following post, respond as if you're commenting on Reddit:
human
If Cacti are known for growing in the harshest of environments, Why don't we see them in non-harsh environments?

They protect themselves from predators, don't need a lot of water. So why don't they dominate vegetation in other places?
gpt
Cacti are incredibly competitive in their environment, meaning they have adaptations to make efficient use of resources in a resource poor environment. However, other species that evolved in higher resource environments are similarly adapted to use more resources effectively, allowing them to out compete cacti which may uptake nutrients more slowly due to their adaptation to extreme environments.