Ecological fitting is a sufficient driver of tight interactions between sunbirds and ornithophilous plants

Abstract

Plant–bird pollination interactions evolved independently on different continents. Specific adaptations can lead to their restriction when potential partners from distant evolutionary trajectories come into contact. Alternatively, these interactions can be enabled by convergent evolution and subsequent ecological fitting. We studied the interactions between New World plants from the genus Heliconia, Asian plants of genus Etlingera and African sunbirds on a local farm in Cameroon. Heliconia spp. evolved together with hummingbirds and Etlingera spp. with spiderhunters —an oriental subgroup of the sunbird family. Sunbirds fed on all studied plants and individual plant species were visited by a different sunbird spectrum. We experimentally documented a higher number of germinated pollen grains in sunbird‐visited flowers of Etlingera spp. For Heliconia spp., this experiment was not successful and pollen tubes were rarely observed, even in hand‐pollinated flowers, where enough pollen was deposited. The analyses of contacts with plant reproductive organs nevertheless confirmed that sunbirds are good pollen vectors for both Heliconia and Etlingera species. Our study demonstrated a high ecological fit between actors of distinct evolutionary history and the general validity of bird‐pollination syndrome. We moreover show that trait matching and niche differentiation are important ecological processes also in semi‐artificial plant‐pollinator systems.

A geographical perspective on the relationship between Impatiens spur lengths and bill lengths of sunbirds in Afrotropical mountains

“…As a result, a long-billed sunbird can be geographically associated with different species of Impatiens plants, however most likely with long floral tubes. This indicates either (a) community assembly based on trait matching (i.e., ecological fitting, Janeček et al, 2020) or (b) community wide adaptations, that is co-evolutionary relationships based on actual trait values in the community rather than strict species-species relationships, which is indicated also by our analyses of higher order correlations (see discussion below). As long-billed sunbirds co-occur with different Impatiens species, the last scenario that sunbirds/Impatiens species prolong their bills/spurs during interactions with different species during their evolutionary history seems to be more likely.…”

Testing for pollinator recognition in multiple species ofHeliconia

“…We targeted species that were common in the living collection at the Organization of Tropical Studies Las Cruces Biological Station, Puntarenas Province, Coto Brus, Costa Rica, (8 47 7 N, 82 57 32 W) and could be found naturally or in ornamental gardens in the area. We required that plants were setting seed when left unmanipulated, indicating that a viable pollen source existed in the area, since previous work on mating systems in Heliconia suggests that the hermaphroditic flowers of many species are self-incompatible to partially self-compatible, but largely not selfing [18,21,[23][24][25][26]. Furthermore, we required that wild, native hummingbirds could be seen visiting the flowers of each target species in camera trap data [27] or during observation, indicating that wild-caught hummingbirds would visit and drink from the flowers inside aviaries despite the fact that many plant species in the collection are not native to Costa Rica.…”

Global vision of heliconias research as cut flower: a review

“…This species harbors a diversity of organisms beneficial to the environment (Benítez-Malvido et al, 2019;Janeček et al, 2019), and provide an ideal habitat for the development of the biological cycle of some insects corresponding to the orders: Diptera, Coleoptera, Himenoptera y Hemiptera, due to the different phenological, structural and environmental conditions generated in the crops (Henao and Ospina, 2008;Foottit and Maw, 2019). Furthermore, these species are mainly pollinated by hummingbirds and bats (Temeles and Bishop, 2019;Torres-Vanegas et al, 2019).…”

“…The possibility of covering the commercial demand throughout the year and the business nature of floricultural production are two important components to participate in the national and international market (Hernández, 2007). Cut flower production is widely adopted in developing countries as a successful economic growth strategy for its ability to generate employment and foreign exchange earnings (Patel-Campillo, 2011).…”