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FRAGMENT FROM NATURE focuses on the biology of spider silk for two weekends followed by a section on the geometry of spider webs. It is not enough that these insects make the toughest material in the planet, but that they also engage in complex geometrical shapes as well. Reminiscent of MC Escher's obsession with tressellations and Kepler's six-fold geometry of snowflakes, the subject of the last two postings. View in LinkedIn

COUPLED STATES. "The coupling of states to dynamics is perhaps most evident for the case of the genome, in which the expressed set of instructions – i.e. the relative level of gene expression – depends on the state of the system - i.e. the composition of the proteome, environmental factors, etc. - that regulate the switching on and off of individual genes." https://lnkd.in/dTS7dFy View in LinkedIn

NEW APPROACH. "This is in marked contrast to the traditional approach to dynamics, where the physical states evolve with time but the dynamical laws remain fixed, or change over much longer time scales." https://lnkd.in/dTS7dFy View in LinkedIn

SECOND EVOLUTION. "The second major shift involves the mechanism of adhesion, from dry cribellate fibrils that adhere through van der Waals forces and hygroscopic interactions to chemically adhesive viscid glue in ecribellate spiders. This results in webs with greater adhesion per surface area and may have facilitated the transition from horizontal to vertical web orientation in modern orb spiders, which is associated with increased prey interception rates." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

SLIPPERY IDEA. "Biological information is a notoriously difficult concept to define. This difficultly stems in part from the fact that in living systems the dynamics are coupled to the information content of biological states such that the dynamics of the system change with the states and vice versa." https://lnkd.in/dTS7dFy View in LinkedIn

FIRST EVOLUTION. "Instead of cribellate and ecribellate orb webs evolving in parallel, orb monophyly explicitly implies that dry cribellate capture spirals were replaced by ecribellate gluey spirals. This involves 2 major changes. First, a shift in the silk used to produce the core fibers of capture threads, resulting in novel tensile properties." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

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