Pollinator Competition as a Driver of Floral Divergence: An Experimental Test.
Optimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2016-01-01
|
| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC4729399?pdf=render |
| _version_ | 1817975560851161088 |
|---|---|
| author | Ethan J Temeles Julia T Newman Jennifer H Newman Se Yeon Cho Alexandra R Mazzotta W John Kress |
| author_facet | Ethan J Temeles Julia T Newman Jennifer H Newman Se Yeon Cho Alexandra R Mazzotta W John Kress |
| author_sort | Ethan J Temeles |
| collection | DOAJ |
| description | Optimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple-throated carib hummingbirds (Anthracothorax jugularis) as the pollinators, red and yellow inflorescence morphs of Heliconia caribaea as the plants, and fluorescent dyes as pollen analogs in an enclosed outdoor garden. When foraging alone, males exhibited a significant preference for the yellow morph of H. caribaea, whereas females exhibited no preference. In competition, males maintained their preference for the yellow morph and through aggression caused females to over-visit the red morph, resulting in resource partitioning. Competition significantly increased within-morph dye transfer (assortative mating) relative to non-competitive environments. Competition and partitioning of color morphs by sexes of purple-throated caribs also resulted in selection for floral divergence as measured by dye deposition on stigmas. Red and yellow morphs did not differ significantly in dye deposition in the competition trials, but differences in dye deposition and preferences for morphs when sexes of purple-throated caribs foraged alone implied fixation of one or the other color morph in the absence of competition. Competition also resulted in selection for divergence in corolla length, with the red morph experiencing directional selection for longer corollas and the yellow morph experiencing stabilizing selection on corolla length. Our results thus support predictions of foraging models of floral divergence and indicate that pollinator competition is a viable mechanism for divergence in floral traits of plants. |
| first_indexed | 2024-04-13T21:51:33Z |
| format | Article |
| id | doaj.art-195288311ee340aa96aa6e7804a05a4c |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-04-13T21:51:33Z |
| publishDate | 2016-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-195288311ee340aa96aa6e7804a05a4c2022-12-22T02:28:24ZengPublic Library of Science (PLoS)PLoS ONE1932-62032016-01-01111e014643110.1371/journal.pone.0146431Pollinator Competition as a Driver of Floral Divergence: An Experimental Test.Ethan J TemelesJulia T NewmanJennifer H NewmanSe Yeon ChoAlexandra R MazzottaW John KressOptimal foraging models of floral divergence predict that competition between two different types of pollinators will result in partitioning, increased assortative mating, and divergence of two floral phenotypes. We tested these predictions in a tropical plant-pollinator system using sexes of purple-throated carib hummingbirds (Anthracothorax jugularis) as the pollinators, red and yellow inflorescence morphs of Heliconia caribaea as the plants, and fluorescent dyes as pollen analogs in an enclosed outdoor garden. When foraging alone, males exhibited a significant preference for the yellow morph of H. caribaea, whereas females exhibited no preference. In competition, males maintained their preference for the yellow morph and through aggression caused females to over-visit the red morph, resulting in resource partitioning. Competition significantly increased within-morph dye transfer (assortative mating) relative to non-competitive environments. Competition and partitioning of color morphs by sexes of purple-throated caribs also resulted in selection for floral divergence as measured by dye deposition on stigmas. Red and yellow morphs did not differ significantly in dye deposition in the competition trials, but differences in dye deposition and preferences for morphs when sexes of purple-throated caribs foraged alone implied fixation of one or the other color morph in the absence of competition. Competition also resulted in selection for divergence in corolla length, with the red morph experiencing directional selection for longer corollas and the yellow morph experiencing stabilizing selection on corolla length. Our results thus support predictions of foraging models of floral divergence and indicate that pollinator competition is a viable mechanism for divergence in floral traits of plants.http://europepmc.org/articles/PMC4729399?pdf=render |
| spellingShingle | Ethan J Temeles Julia T Newman Jennifer H Newman Se Yeon Cho Alexandra R Mazzotta W John Kress Pollinator Competition as a Driver of Floral Divergence: An Experimental Test. PLoS ONE |
| title | Pollinator Competition as a Driver of Floral Divergence: An Experimental Test. |
| title_full | Pollinator Competition as a Driver of Floral Divergence: An Experimental Test. |
| title_fullStr | Pollinator Competition as a Driver of Floral Divergence: An Experimental Test. |
| title_full_unstemmed | Pollinator Competition as a Driver of Floral Divergence: An Experimental Test. |
| title_short | Pollinator Competition as a Driver of Floral Divergence: An Experimental Test. |
| title_sort | pollinator competition as a driver of floral divergence an experimental test |
| url | http://europepmc.org/articles/PMC4729399?pdf=render |
| work_keys_str_mv | AT ethanjtemeles pollinatorcompetitionasadriveroffloraldivergenceanexperimentaltest AT juliatnewman pollinatorcompetitionasadriveroffloraldivergenceanexperimentaltest AT jenniferhnewman pollinatorcompetitionasadriveroffloraldivergenceanexperimentaltest AT seyeoncho pollinatorcompetitionasadriveroffloraldivergenceanexperimentaltest AT alexandrarmazzotta pollinatorcompetitionasadriveroffloraldivergenceanexperimentaltest AT wjohnkress pollinatorcompetitionasadriveroffloraldivergenceanexperimentaltest |