Can differential nutrient extraction explain property variations in a predatory trap?

Abstract

Predators exhibit flexible foraging to facilitate taking prey that offer important nutrients. Because trap-building predators have limited control over the prey they encounter, differential nutrient extraction and trap architectural flexibility may be used as a means of prey selection. Here, we tested whether differential nutrient extraction induces flexibility in architecture and stickiness of a spider's web by feeding Nephila pilipes live crickets (CC), live flies (FF), dead crickets with the web stimulated by flies (CD) or dead flies with the web stimulated by crickets (FD). Spiders in the CD group consumed less protein per mass of lipid or carbohydrate, and spiders in the FF group consumed less carbohydrates per mass of protein. Spiders from the CD group built stickier webs that used less silk, whereas spiders in the FF group built webs with more radii, greater catching areas and more silk, compared with other treatments. Our results suggest that differential nutrient extraction is a likely explanation for prey-induced spider web architecture and stickiness variations.

Ontogenetic shift toward stronger, tougher silk of a web‐building, cave‐dwelling spider

“…Samples of MAS were extracted from web sections across 10 mm wide U‐shaped frames cut out of one end of 76 mm × 26 mm cardboard cards following Blamires et al . (). Original tension of the silk samples within webs was preserved using double‐sided sticky tape applied to the edges of the U‐shaped frames to adhere to the silk threads during extraction.…”

“…Sections of sampled H. troglodytes webs were immediately transported (taking up to 2 weeks in transit) from the field to the laboratory at Tunghai University, Taiwan, whereupon 1-2 undamaged and accessible MAS threads of 10-15 mm in length were sub-sampled from each web section. Samples of MAS were extracted from web sections across 10 mm wide U-shaped frames cut out of one end of 76 mm 9 26 mm cardboard cards following Blamires et al (2015). Original tension of the silk samples within webs was preserved using double-sided sticky tape applied to the edges of the U-shaped frames to adhere to the silk threads during extraction.…”

“…Original tension of the silk samples within webs was preserved using double-sided sticky tape applied to the edges of the U-shaped frames to adhere to the silk threads during extraction. Elmer's â glue was then applied atop the MAS thread affixed to the tape to further affix the silk thread to the frame; similar to how other studies have affixed gluey capture silks from orb webs and cobwebs to similar sized frames (Blackledge & Hayashi, 2006;Blamires et al, 2015). Cyanoacrylate glue is sometimes used to affix silk threads to paper frames (Blackledge & Hayashi, 2006;Agnarsson, Kuntner & Blackledge, 2010).…”

Life history trade-offs imposed by dragline use in two money spiders

“…Based on conservative assumptions (Prestwich, 1977), 18% of all costs are related to spinning activity, the remainder to physiological silk production costs. Variation in protein (Blamires et al, 2012a) and carbohydrate (Blamires et al, 2015) intake determines the amino acid composition of silk and the architectural plasticity of the produced webs. Both silk production and silk spinning are therefore highly dependent on nutritional intake.…”

The Complexity Based Analysis of the Correlation between Spider’s Brain Signal and Web

“…Between all studies done on animal behavior, spiders have aroused the attention of some scientists [1][2][3][4][5].An important behavior of spiders is building the web and several works have been done on studying this behavior [6][7].Between these works, few scientists have tried to analyze the behavior of spider on building its web by applying drugs on spider. The first study refers to the work done by Witt [8] in 1948.…”