Format

Send to

Choose Destination
Evolution. 2016 Mar;70(3):716-24. doi: 10.1111/evo.12881. Epub 2016 Mar 4.

Strong pollinator-mediated selection for increased flower brightness and contrast in a deceptive orchid.

Author information

1
Department of Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 D, SE-752 36, Uppsala, Sweden. nina.sletvold@ebc.uu.se.
2
Department of Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 D, SE-752 36, Uppsala, Sweden.

Abstract

Contrasting flower color patterns that putatively attract or direct pollinators toward a reward are common among angiosperms. In the deceptive orchid Anacamptis morio, the lower petal, which makes up most of the floral display, has a light central patch with dark markings. Within populations, there is pronounced variation in petal brightness, patch size, amount of dark markings, and contrast between patch and petal margin. We tested whether pollinators mediate selection on these color traits and on morphology (plant height, number of flowers, corolla size, spur length), and whether selection is consistent with facilitated or negative frequency-dependent pollination. Pollinators mediated strong selection for increased petal brightness (Δβpoll = 0.42) and contrast (Δβpoll = 0.51). Pollinators also tended to mediate stabilizing selection on brightness (Δγpoll = -0.27, n.s.) favoring the most common phenotype in the population. Selection for reduced petal brightness among hand-pollinated plants indicated a fitness cost associated with brightness. The results demonstrate that flower color traits influence pollination success and seed production in A. morio, indicating that they affect attractiveness to pollinators, efficiency of pollen transfer, or both. The documented selection is consistent with facilitated pollination and selection for color convergence toward cooccurring rewarding species.

KEYWORDS:

Anacamptis morio; facilitation; floral evolution; flower color; natural selection; plant-animal interactions; pollination by deceit

PMID:
26878831
DOI:
10.1111/evo.12881
[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center