Orchid sexual deceit provokes ejaculation.

Area of Science:

• Evolutionary Biology
• Plant-Pollinator Interactions
• Sexual Deception

Background:

• Sexually deceptive orchids mimic female insects to attract male pollinators.
• Pollinator costs associated with this deception were previously underestimated.

Purpose of the Study:

• To investigate the costs of sexual deception on pollinators.
• To understand how deceptive pollination persists despite pollinator costs.

Main Methods:

• Observational studies on Australian tongue orchids (Cryptostylis species).
• Analysis of pollinator behavior, including ejaculation and sperm wastage.
• Correlation of pollination success with pollinator behavior.

Main Results:

• Pollinating insects frequently ejaculate, resulting in significant sperm wastage.
• Orchid species inducing extreme pollinator responses exhibit higher pollination success.
• Solitary, haplodiploid pollinators are key, as females can still produce male offspring.

Conclusions:

• Pollinator sperm wastage represents a considerable cost, potentially driving coevolution.
• Despite costs, sexual deception persists due to reproductive benefits for certain pollinator types.
• Orchid mimicry and pollinator learning may be locked in an evolutionary arms race.