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Ploy and counterploy in predator-prey interactions: Orb-weaving spiders versus bombardier beetles
1Section of Neurobiology and Behavior, Division of Biological Sciences, Cornell University, Ithaca, New York 14853.
Summary
Orb-weaving spiders capture bombardier beetles using different strategies. One spider wraps the beetle, avoiding its defensive spray, while another is repelled by the spray and loses the beetle.
Area of Science:
- * Behavioral ecology
- * Predator-prey interactions
- * Chemical defense mechanisms
Background:
- * Bombardier beetles (Brachinus spp.) possess a potent chemical defense spray.
- * Orb-weaving spiders exhibit diverse predation strategies.
- * Interactions between these species present a unique case study in evolutionary adaptations.
Purpose of the Study:
- * To investigate the attack and capture strategies of two orb-weaving spider species when presented with bombardier beetles.
- * To determine the effectiveness of spider predation techniques against the beetle's chemical defenses.
- * To explore the adaptive significance of spider silk-wrapping behavior.
Main Methods:
- * Observation of predatory interactions between spiders (Nephila clavipes and Argiope spp.) and bombardier beetles.
- * Analysis of spider capture and handling techniques.
- * Assessment of beetle defensive spray deployment and its impact on spider behavior.
Main Results:
- * Nephila clavipes directly grasps beetles, is repelled by the defensive spray, and loses the prey.
- * Argiope spp. initially wrap beetles in silk, preventing spray release and enabling successful capture.
- * Silk wrapping effectively neutralizes the beetle's chemical defense during predation.
Conclusions:
- * Spider predation strategies significantly influence the outcome of encounters with bombardier beetles.
- * Silk wrapping is an effective adaptation for spiders to overcome chemical defenses in prey.
- * This strategy may be a key factor in the evolution of spider silk use against chemically protected insects.
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