Raptorial jaws in the throat help moray eels swallow large prey

Area of Science:

• Ichthyology
• Vertebrate Paleontology
• Biomechanics

Background:

• Bony fishes typically use suction feeding and pharyngeal jaws for prey transport.
• Moray eels exhibit reduced suction-feeding capabilities, posing a challenge for prey ingestion.
• The mechanism by which moray eels swallow large prey remains largely unknown.

Purpose of the Study:

• To investigate the feeding mechanism of moray eels, specifically how they swallow large prey.
• To identify the role and function of pharyngeal jaws in moray eel feeding.
• To understand the evolutionary adaptations enabling moray eels to overcome reduced suction capacity.

Main Methods:

• Observation of feeding behavior in Muraena retifera.
• Analysis of pharyngeal jaw morphology and musculature.
• Comparative biomechanical analysis with other vertebrates.

Main Results:

• Moray eels launch raptorial pharyngeal jaws from the throat into the oral cavity to grasp prey.
• These pharyngeal jaws restrain and transport prey to the esophagus, compensating for weak suction.
• This represents a novel prey transport mechanism in teleost fishes, distinct from hydraulic transport.

Conclusions:

• Moray eels possess a unique predatory adaptation involving highly mobile pharyngeal jaws for prey capture and transport.
• This innovation likely contributed to their success as apex predators in complex reef environments.
• The pharyngeal jaw mechanism shows convergent evolution with the ratcheting mechanisms found in snakes.