Chelsea found that the Costaceae had converged upon bird pollination four separate times — each resulting in a lineage with bright red tubular flowers. These Costaceae lineages are native to Central America, South America, and Southeast Asia. In Central and South America, such flowers are pollinated by hummingbirds — but hummingbirds don’t live in Southeast Asia! So who is pollinating those Southeast Asian Costaceae with their stunning red flowers?
Well, it turns out that hummingbirds aren’t the only birds to have evolved the fast and furious lifestyle of a nectar feeder. Sunbirds, which do live in Southeast Asia, are also small and fleet, with brightly-colored plumage and long beaks for reaching deep into flowers. Sunbirds (and other nectar-feeding birds) take advantage of the nectar rewards offered by plants such as Tapeinochilos (shown above) and, in turn, help pollinate them.
Despite these similarities, sunbirds and hummingbirds are not very closely related. In fact, hummingbirds are more closely related to swifts and sunbirds are more closely related to crows — so the striking similarities between these two groups of tiny, colorful birds are analogies that evolved through convergent evolution.
Interestingly, one of the few obvious differences between sunbirds and hummingbirds is that hummingbirds can hover at a food source, but sunbirds must perch in order sip nectar from a flower. The plants pollinated by each have evolved accordingly: hummingbird-pollinated plants have no place to perch, but sunbird-pollinated plants have heavy-duty modified leaves, called bracts, that make great perches!