Questions: Bromeliads and other tropical plants live in and on rainforest trees, obtaining food and living space from the trees but not helping or harming them. What type of association do trees and bromeliads have, and how much coevolution is occurring to maintain this relationship? Commensalism; significant coevolution Mutualism; little or no coevolution Mutualism: significant coevolution Commensalism: little or no coevolution

The answer is the last one: Commensalism; little or no coevolution.

Explanation for each option:

1. Commensalism; significant coevolution: This option is incorrect because commensalism is a type of relationship where one organism benefits while the other is neither helped nor harmed. Significant coevolution typically occurs in relationships where both species are affected, such as mutualism or parasitism.

2. Mutualism; little or no coevolution: This option is incorrect because mutualism involves a relationship where both species benefit, which is not the case here. Additionally, mutualistic relationships often involve some degree of coevolution.

3. Mutualism; significant coevolution: This option is incorrect for the same reasons as the previous one. The relationship described is not mutualistic, and significant coevolution is not expected in a commensal relationship.

4. Commensalism; little or no coevolution: This is the correct answer. In a commensal relationship, like that between bromeliads and rainforest trees, one species benefits (bromeliads) while the other (trees) is unaffected. There is typically little or no coevolution because the trees do not derive any benefit or harm from the bromeliads, so there is no evolutionary pressure for the trees to adapt in response to the bromeliads.