How do bee-pollinated orchids attract bees?

Orchids attract bees through a variety of sophisticated strategies, ranging from offering rewards to complex forms of deception.

Reward-Based Attraction

Many orchids attract bees by providing food, typically in the form of nectar. These flowers often feature:
* Visual Cues: Bright colors (excluding red, which bees cannot perceive) and nectar guides—colored lines that direct bees toward the flower's center.1
* Structural Design: A landing platform and a tunnel-like structure formed by the lip and column. As a bee enters to reach the concealed nectary, it brushes against the reproductive parts, facilitating the transfer of pollen.1

Deceptive Attraction

Some orchids rely on manipulation rather than food rewards:
* Sexual Deception: Genera such as Ophrys use a process called pseudocopulation. The flower mimics the appearance, tactile feel, and scent (pheromones) of a female bee. Male bees are lured to the flower, attempting to mate with the labellum, during which they inadvertently collect or deposit pollen.23
* Odor Attraction: Male euglossine bees are attracted to specific floral scents, which they collect and store in their hind legs. In some cases, such as the genus Coryanthes, the orchid uses this attraction to trap the bee in a water-filled bucket, forcing it to exit through a tunnel where pollen is deposited on its body.1
* Pseudoantagonism: Some orchids simulate an enemy insect, prompting male bees to strike the flower in an attempt to defend their territory, which results in pollen attachment.1