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COMBINED CHARACTERISTICS. "In reality, the combination of characteristics of araneoid orb-webs—their vertical orientation, greater ability to dissipate prey energy, increased stickiness and greater economy—are all likely to have contributed to the greater success and diversity of this group. Not only do these traits improve prey capture potential, but they also allow spiders to occupy new niches." https://lnkd.in/dqTjK77 View in LinkedIn

MASSIVE EXTENSIBILITY. "While untested, the high extensibility of viscid silk (up to 1000%) may add an additional safety factor preventing breakage, as a struggling insect is unlikely to extend the silk this far." https://lnkd.in/dqTjK77 View in LinkedIn

FUNCTION OF STICKINESS. "Stickiness of viscid silk is ultimately constrained by the tensile strength of its axial fibres. Stickiness increases linearly with tensile strength, but is always less than the force required to break the axial fibres. This safety factor allows threads to repeatedly detach and reattach to prey, rather than breaking, as prey struggle to escape the web." https://lnkd.in/dqTjK77 View in LinkedIn

DUPONT once had an advert in CE&N showing a suspension bridge made of spider silk and a text claiming that a single cable of silk could hold back a jet. The US army dreamed of making lightweight bulletproof alternatives to Kevlar. At an earlier point in my own life I was engaged in an effort to clone the spider silk gene. Recently, recombinant and functional spider silk has been reported, along with heterologous host systems, but scale-up remains a considerable challenge. https://lnkd.in/dmvrhKR View in LinkedIn

WEB STICKINESS. "Stickiness is further enhanced by a ‘suspension bridge mechanism’ that recruits adhesion from neighbouring glue droplets, reducing the tendency of capture threads to peel away from prey cuticle. Moreover, the glue droplets act as viscoelastic solids that achieve greater stickiness under fast deformation when insects first impact webs, but also maintain adhesion for long periods under static loading." https://lnkd.in/dqTjK77 View in LinkedIn

VARIATION DRIVERS. "Individual variation in orb-web structure is well documented and arises for a variety of reasons. Individual spiders adjust web characteristics (e.g. thread spacing, top/bottom asymmetry and area) to suit local conditions. Important factors include the types of prey available, overall prey availability, nutritional status, weather conditions, spider size, age and development, silk supply, experience, the presence of predators and parasites and microhabitat structure." https://lnkd.in/dqTjK77 View in LinkedIn

CAPTURE VISCID SILK. "The glue droplets are composed of about 80 per cent water as well as glycoproteins that adhere to prey and small hygroscopic molecules. Viscid silk is stickier per volume when compared with cribellate silk, which increases prey capture potential and ultimately spider fitness." https://lnkd.in/dqTjK77 View in LinkedIn

MEASURING LEG. "The form of a spider's web can be seen as a representation of inherited rules of behaviour, although the geometry of the orb web is not rigidly predetermined. The garden spider Araneus diadematus Clerk orients the main (capture) spiral of the web according to measurements taken by particular legs. This is apparent when a measuring leg has been regenerated, because the reduced length of the regenerate is reflected in the geometry of the capture spiral." https://lnkd.in/dfgxXRZ View in LinkedIn

SPIDER VISCID SILK. "Araneoid capture silk, often referred to as viscid or sticky silk, is more economical to produce because of an alternative mechanism of adhesion. As the axial fibres are extruded from the flagelliform glands, an aqueous glue coating is simultaneously deposited from the aggregate glands onto the axial fibres and coalesces into microscopic droplets along the fibre's length." https://lnkd.in/dqTjK77 View in LinkedIn

WIDE BELL CURVE. "In addition to variability among silks types, there is substantial inherent variability in silk properties within the same silk types produced by individual spiders. This may be in part owing to variation in silk fibroin gene sequences and heterogeneous nanoscale morphology of silk fibres." https://lnkd.in/dqTjK77 View in LinkedIn