What does the directed-pollination hypothesis suggest?
1. Plants are only directly pollinated when other plants of the same species are nearby.
2. Plants that self-pollinate are directed (triggered) to do so by the absence of nearby plants of their species.
3. Natural selection has favored flower traits (scent, shape, color) that attract pollinating animals.
4. Pollination is a process that is directed (triggered) by key plant hormones.