Some Plants Gave up the Ability to Get Energy from the Sun
Photosynthesis is one of the most unheralded superpowers possessed by any modern creature. It provides "food" for plants, and thereby becomes the most primary building block of entire ecosystems. We just spent 15 minutes making and eating a sandwich, whereas if we had photosynthetic superpowers, we could've just raised our window blinds.
Still, as amazing as photosynthesis is, there are members of the plant kingdom that have found it to be an inhibition to their survival. http://www.ftexploring.com/askdrg/askdrg6.html . Naturally, converting sunlight into food takes energy, and there are parasitic plants which have found that this energy could better be used spreading out all over a host. Myco-heterophytes attach themselves to trees, the trees use photosynthesis and transfer the nutrients to the parasitic plant, which uses the saved energy to cover even more of the tree.