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TRANSITIONS DRIVEN BY INFORMATION. "We propose that these major transitions, corresponding to major jumps in biological complexity, are associated with information gaining causal efficacy over higher levels of organization." https://lnkd.in/dTS7dFy View in LinkedIn

WEB LOSS. "Although the orb has been lost independently at least 3 times within the context of our current taxon sampling, it has likely been lost even more frequently among all orb-weavers." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

MISSING PARTS. "More generally, while it is true that changes in how information is stored and transmitted enable the possibility of new levels of organization to evolve, such innovations are not necessarily a sufficient causative agent to drive the emergence of genuinely new, higher-level, entities." https://lnkd.in/dTS7dFy View in LinkedIn

SPIDER WEB EVOLUTION. "Subsequent to the orb's origin, aqueous viscid silk replaced cribellate silk and the orb was transformed at least 3 times into less regular appearing aerial sheet webs. Moreover, the orb web has been highly reduced independently in tetragnathoids and Araneidae." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

HARD TO ANSWER. "Plenty of protists are capable of phenotypic differentiation but have never made the transition to true multicellularity, although they may exhibit highly collective and coordinated behaviors." https://lnkd.in/dTS7dFy View in LinkedIn

ORB WEB GEOMETRY. "Our analysis shows that orb webs arose a single time. The orb appears to be derived from a substrate-bound web, likely an irregular ground web or brushed sheet web. The evolution of orb webs was marked by a dramatic increase in geometric regularity, resulting from increased behavioral stereotypy of spinning." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

DIVERSIFIED BY SILK. "In contrast to megadiverse orders of insects, evolutionary diversification of spiders is not coupled with major trophic shifts. Spider diversification is instead linked to key innovations in silk use." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

AERIAL WEB EVOLUTION. "The Orbiculariae, so named for the classic orb-web they build, account for more than 25 per cent of spider diversity (11 880 + species). The evolution of the orb-web meant that spiders could build aerial webs suspended in space, freeing them from the limitations in web shape imposed by the substrate. The move to building aerial webs may represent the beginnings of an evolutionary arms race with flying insects that co-radiated alongside the spiders." https://lnkd.in/dHWBg9g View in LinkedIn

DIVERSITY AT ALL SCALES. "Some nanoscale structures within dragline silk (e.g. β-sheet crystals, β-turns) are found in most spider species. However, variation in biomechanical function can arise owing to diversity in silks at all structural scales." https://lnkd.in/dHWBg9g View in LinkedIn

SILK ELASTICITY BIOCHEMISTRY. "In addition to its strength, dragline silk is highly elastic when compared with synthetic fibres. Elasticity of dragline silk is determined largely by the semi-amorphous regions interconnecting the β-sheet crystals. These regions include helix-like structures and β-turns that are rich in glycine. When a silk fibre is subjected to tensile loading, the semi-amorphous regions unravel first owing to breaking of hydrogen bonds, which accounts for the high level of extensibility observed in silk." https://lnkd.in/dHWBg9g View in LinkedIn