‘Ilie‘e (Plumbago zeylanica) — My Goto for the 3Ws.

    

    Whenever I'm with a group of students or volunteers, the sticky fruits of ‘ilie‘e are my goto to get them to imagine how Hawai‘i's native plants first arrived in the Islands, the most remote island chain in the world (more than 2,000 miles away from California and nearly 4,000 miles from Japan). If you don't already know, scientists believe the founder (i.e., first) plants (and animals too) to make it to Hawai‘i, arrived here via one of the 3Ws — wind, water, or wings — a powerful mnemonic. ‘IIie‘e, an indigenous species, almost certainly got to the Islands when a bird preened one of its sticky fruits from its feathers and it fell to Hawai‘i's virgin ground. The founders of other native plants such as naupaka kahakai likely arrived as fruits floating on Pacific Ocean waves, while others like Hawai‘i's native ferns arrived here as tiny spores adrift in the wind from distant lands. Biologists (according to Ziegler 2002) estimate that 95% of Hawai‘i's native ferns and 2% of its native flowering plants got to the Hawaiian Islands via the wind, none of Hawai‘i's native ferns and 23% of its native flowering plants got to the Islands by water, and 5% of Hawai‘i's native ferns and 75% of its native flowering plants got to the Islands via birds. The prevailing eastward winds and numerous stepping-stone islands to the west of Hawai‘i have resulted in a slight majority of these founder plants coming from Asia even though Hawai‘i is geographically closer to the Americas. Prior to humans, the arrival of new plants in Hawai‘i was extremely rare, with only one new species establishing itself every 105,000 years for flowering plants and every 265,000 years for ferns.