# Experimental evidence of pollination by deception in a dioecious palm

## TL;DR

This study shows how a type of palm uses scent to attract pollinators to both male and female flowers, even though they open at different times.

## Contribution

The study provides experimental evidence of pollination by deception using artificial flowers in a dioecious palm species.

## Key findings

- Female and male inflorescences emit consistent floral odors throughout the day.
- Artificial flowers with different p-methylanisole amounts attracted similar insect diversity and abundance.
- Intersexual mimicry in the palm is sustained by consistent odor release, not opening time differences.

## Abstract

Flower traits and pollinator activity patterns can vary over the course of a single day. Therefore, the pollination processes occurring over short time scales are crucial to sustain the complex dynamics of plant-pollinator interactions. Here, we characterized the diel patterns of flower opening (e.g. anthesis), scent emission, and insect visits in highly dimorphic male (rewarding) and female (deceptive) inflorescences of the ivory palm (Phytelephas aequatorialis), a thermogenic dioecious species endemic to western Ecuador. We conducted field experiments using artificial scented-baits (designated as artificial flowers) consisting of a heating plate (simulating thermogenesis) and p-methylanisole (the primary odor compound in inflorescences of both sexes) in two different amounts to mimic female and male inflorescences.

We found that female inflorescences open synchronously at dawn and dusk, while male inflorescences can open at any time throughout the day. Both sexes emitted floral odors consistently throughout the day. Even though male inflorescences emitted greater quantities of p-methylanisole, artificial flowers with different amounts of p-methylanisole attracted a similar diversity and abundance of insects throughout the day. Furthermore, male and female artificial flower attracted an equal abundance of visitors within five minutes of the emission of p-methylanisole.

The findings suggest that, despite sexual dimorphism in opening time, intersexual mimicry in P. aequatorialis is sustained by a consistent odor release, which optimizes the probability of both sexes being visited by the same insect community during the day.

The online version contains supplementary material available at 10.1186/s12862-025-02388-6.