Related Experiment Video
Updated: Jun 11, 2026
07:19
Field Experiments of Pollination Ecology: The Case of Lycoris sanguinea var. sanguinea
Published on: November 25, 2016
Differential pollinator importance contributes to flower colour variation along an elevational gradient
Jonathan Heinze1, Casper J van der Kooi2, Johannes Spaethe1
1Department of Behavioural Physiology and Sociobiology, Biocentre, University of Würzburg, Würzburg, Germany.
Biology Letters
|June 10, 2026
Summary
Beetles are more effective pollinators than honeybees for Anemone pavonina flowers, especially at lower elevations. This explains why flower specialization shifts to bees at higher elevations where beetles are absent, creating an elevational color gradient.
Area of Science:
- Ecology
- Evolutionary Biology
- Botany
Background:
- Floral diversity in angiosperms is often driven by pollinator-mediated selection.
- Mediterranean red flowers typically attract beetles (Glaphyridae) and bees, but can specialize on bees in beetle-absent areas like high elevations.
- The color polymorphism in Anemone pavonina presents an opportunity to study pollinator specialization.
Purpose of the Study:
- To assess the pollination effectiveness of honeybees and beetles for the color-polymorphic Anemone pavonina.
- To understand the factors driving apparent floral specialization along an elevational gradient.
- To investigate the role of pollinator importance in shaping floral traits and color.
Main Methods:
- Studied natural populations of Anemone pavonina along the slope of Mount Olympus, Greece.
- Recorded flower visit duration and frequency for honeybees and Pygopleurus beetles.
- Quantified single-visit seed set to determine per-visit pollination effectiveness.
Main Results:
- Beetles demonstrated significantly higher per-visit pollination effectiveness (36.3% seed set) compared to honeybees (9.5%).
- Beetle visits were substantially longer (56 seconds) than honeybee visits (2 seconds).
- Beetle pollinator importance decreased with elevation, while bee pollinator importance remained constant but low, exceeding beetles only at higher elevations.
Conclusions:
- Floral specialization for beetle pollination is advantageous at lower elevations due to higher beetle pollinator importance.
- Specialization for bee pollination becomes beneficial at higher elevations where beetle presence is limited.
- Differential pollinator importance along the elevational gradient contributes to the observed flower color gradient in Anemone pavonina.
Related Concept Videos
02:40Pollination and Flower Structure
Flowers are the reproductive, seed-producing structures of angiosperms. Typically, flowers consist of sepals, petals, stamens, and carpels. Sepals and petals are the vegetative flower organs. Stamens and carpels are the reproductive organs.
01:21Frequency-dependent Selection
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.Positive Frequency-Dependent SelectionIn positive...
01:20Mate Choice
Mate choice—the decision about whom to mate with—is a type of natural selection, since animals must reproduce to pass down their genes. Mate choice is also called intersexual selection because the behavior occurs between the sexes.
02:16Genetics of Speciation
Speciation is the evolutionary process resulting in the formation of new, distinct species—groups of reproductively isolated populations.The genetics of speciation involves the different traits or isolating mechanisms preventing gene exchange, leading to reproductive isolation. Reproductive isolation can be due to reproductive barriers that have effects either before or after the formation of a zygote. Pre-zygotic mechanisms prevent fertilization from occurring, and post-zygotic mechanisms...
01:43Incomplete Dominance
Gregor Mendel's work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid cell has two variants called alleles inherited from each parent. He suggested that amongst these two alleles, one allele is dominant in character and the other recessive. The combination of alleles determines the phenotype of a gene in an organism.
01:46Types of Selection
Natural selection influences the frequencies of particular alleles and phenotypes within populations in several different ways. Primarily, natural selection can be directional, stabilizing, or disruptive. Directional selection favors one extreme trait and shifts the population towards that phenotype while selecting against individuals displaying alternate traits. Stabilizing selection favors an intermediate trait with a narrow range of variation. Deviation from the optimal phenotype towards an...