The Hawaiian silversword originated from a species of tarweed, which is a plant native to present-day California. This plant colonized the Hawaiian islands approximately 5 million years ago, and currently consists of 30 species that are monophyletic, rapidly speciated, and have diversified ecologically into many different niches. This type of colonization is referred to as a/an ____________.
A) adaptive radiation
B) convergent evolution
C) polytomy
D) synapomorphy