Aggressive mimicry in a coral reef fish: The prey's view

Area of Science:

• Marine Biology
• Evolutionary Ecology
• Sensory Ecology

Background:

• Mimicry relies on perceptual deception, making receiver sensory ecology crucial for understanding signal evolution.
• Coral reef fish, specifically color-polymorphic *Hypoplectus* hamlets, are investigated for aggressive mimicry.
• Understanding mimicry requires examining the perspective of the intended receiver, in this case, prey species.

Purpose of the Study:

• To test the potential for aggressive mimicry in *Hypoplectus* hamlets from the viewpoint of their prey.
• To investigate the preconditions for mimicry, specifically model-mimic misidentification.
• To gain insights into the origin and evolutionary trajectory of mimicry signals in coral reef fish.

Main Methods:

• Construction of visual models based on prey visual pigments and spatial resolution.
• Analysis of underwater light spectrum and color reflectances of putative models and hamlet mimics.
• Evaluation of mimic-model relationships from the sensory ecology perspective of prey (gobies and mysid shrimp).

Main Results:

• Evidence supports a mimic-model relationship between the butter hamlet (*H. unicolor*) and the butterflyfish (*Chaetodon capistratus*).
• Evidence does not support a mimic-model relationship between the black hamlet (*H. nigricans*) and the dusky damselfish (*Stegastes adustus*).
• The findings are discussed in the context of color morph divergence within the *Hypoplectus* radiation.

Conclusions:

• Aggressive mimicry in *H. unicolor* may have originated from protective (Batesian) mimicry against fish predators, rather than aggressive mimicry driven by prey.
• The study highlights the importance of receiver's sensory ecology in validating mimicry hypotheses.
• Results contribute to understanding the evolutionary pathways of mimicry in coral reef fish species.