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Portia's capacity to decide whether a detour is necessary
Fiona R Cross1,2,3, Robert R Jackson4,2
1School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch, New Zealand fiona.r.cross@gmail.com.
The Journal of Experimental Biology
|July 27, 2019
Summary
Jumping spiders (Portia africana) strategically decide whether to use a detour or direct path to reach prey. They favor direct routes when available, demonstrating advanced predatory decision-making.
Area of Science:
- Behavioral Ecology
- Arachnology
- Animal Cognition
Background:
- The predatory behavior of *Portia* spiders is complex, involving sophisticated planning.
- While their ability to choose detour routes is known, their decision-making regarding the necessity of detours is less understood.
Purpose of the Study:
- To investigate the strategic decision-making of *Portia africana* regarding the use of detour paths versus direct access.
- To determine if *Portia africana* can assess the need for a detour based on prey availability.
Main Methods:
- Experiments used *Portia africana* with lures (prey or leaf pieces) initially visible.
- Water was used to restrict spider movement, and both detour and causeway paths were provided.
- Lure visibility was manipulated to assess decision-making under different conditions.
Main Results:
- *Portia africana* preferentially used the causeway for direct access when prey lures were present and the causeway was available.
- When the causeway was absent, spiders more frequently chose the detour path to reach prey.
- Spiders did not take the detour path when presented with non-prey (leaf pieces).
Conclusions:
- *Portia africana* demonstrates strategic decision-making in prey acquisition, assessing the necessity of detours.
- The spiders effectively differentiate between direct and indirect routes based on the presence and type of lure.
- This study highlights advanced cognitive abilities in *Portia* spiders' predatory strategies.
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