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Artificial spider silk View in LinkedIn

ORB-WEB ORIGINS. "Recent evidence that combines both morphological and molecular data indicates that linyphiid sheet-webs and theridiid cobwebs each evolved independently from orb-webs. The huge diversity within these families, along with the frequent reduction of orb-webs within the ‘traditional’ orb-spinning families, suggests that the orb-web has provided a platform for the further rapid evolution of novel web structures." https://lnkd.in/dqTjK77 View in LinkedIn

EVOLUTIONARY TRENDS. "In addition to modified orb-webs for prey specialization, there is a strong evolutionary trend among derived orbicularian spiders towards smaller body and web size, as well as for webs that enclose three-dimensional spaces." https://lnkd.in/dqTjK77 View in LinkedIn

"SPECIALIST WEBS are in most cases greatly reduced in size and complexity when compared with typical orbs, in the most extreme cases consisting of only single lines of silk. Particularly for reduced webs, spiders cannot rely on the highly geometric orb-web structure to assist in energy dissipation and must instead depend to a greater extent on the biomechanical properties of individual silk threads." https://lnkd.in/dqTjK77 View in LinkedIn

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