Mass predicts web asymmetry in Nephila spiders

摘要: The architecture of vertical aerial orb webs may be affected by spider size and gravity or the available web space, in addition to phylogenetic and/or developmental factors. Vertical asymmetry measured hub displacement has been shown increase bigger heavier spiders; however, previous studies have mostly focused on adult subadult spiders several classes with parameters but no mass. Both estimations are suboptimal because (1) not invest heavily optimal construction, whereas juveniles do; (2) class/developmental stage is difficult estimate field thus subjective, (3) mass scales differently therefore more important predicting foraging success due gravity. We studied a giant spider, Nephila pilipes, across wide range classes/developmental stages tested hypothesis that (measured as displacement) On sample 100 webs, we found hubs were displaced larger explained better than other measures (carapace leg lengths, stage). Quantifying shape via ladder index suggested that, unlike nephilid taxa, growing orbs do become vertically elongated. conclude ontogenetic pattern progressive can gravity, which opposing selective force high web-building costs lower orb. Recent literature finds little support for alternative explanations allometry such limitation biogenetic law.