Interpretations of orb-web variability: A review of past and current ideas

The understanding of web-building behaviour in orb-web spiders has undergone several paradigm shifts. In the past, orb-web construction was assumed to be limited to genetically-controlled design patterns, suggesting that meaningful variation only existed at the species level. Subsequently, it was recognised that variation in web design also exists within species and that this variation was linked to the prey capture ability of webs. Another approach to interpreting individual variation is within a decision-making construct. The web-building decisions of spiders may thus be ruled by algorithms or mechanical constraints. Similarly, individual decisions may reflect foraging strategies aimed to maximise food intake. Our own work suggests that experience in web-building and prey capture may also contribute to individual variation of orb-web design. Using several key publications as well as recently collected data we discuss past and current ideas to interpret orb-web variability.