The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the age of the dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition from the pollen and shelter from the microsporophylls. Upon visiting megasporophylls, the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesise neurotoxins, especially in the seeds, that are effective against most animals, including humans.
-If the beetles survive by consuming cycad pollen, then whether the beetles should be considered mutualists with, or parasites of, the cycads depends upon the ________.

Question

Quizplus · Accepted Answer

Whether the beetles should be considered mutualists or parasites of the cycads depends on the extent to which their overall activities, including consuming cycad pollen, affect cycad reproduction. If the beetles effectively pollinate the cycads, then they would be considered mutualists, but if they negatively impact cycad reproduction, then they would be considered parasites. The other answer choices are not directly related to determining whether the beetles are mutualists or parasites.

The Cycads, a Mostly Tropical Phylum of Gymnosperms, Evolved About