Year: 2022

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

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

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

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

"NATURAL MATERIALS are renowned for exquisite designs that optimize function, as illustrated by the elasticity of blood vessels, the toughness of bone and the protection offered by nacre. Particularly intriguing are spider silks, with studies having explored properties ranging from their protein sequence to the geometry of a web. This material system, highly adapted to meet a spider’s many needs, has superior mechanical properties." https://lnkd.in/dTx-Ej8 View in LinkedIn

TOUGHEST MATERIAL. "Spiders produce multiple silk types, from discrete abdominal glands, that exhibit remarkable strength and elasticity surpassing most natural and artificial fibres, and they are unmatched in toughness." https://lnkd.in/dHWBg9g View in LinkedIn

ONE ANCESTRAL TREE. "The monophyletic origin of orb webs is strongly supported, despite conspicuous differences in the silk used to spin different types of orbs." https://lnkd.in/db9PJGx View in LinkedIn

THUMBNAIL OVERVIEW. "Spiders first began spinning silk approximately 400 Ma. There are at least 41 000 described species of spiders spinning silk in every known terrestrial ecosystem except Antarctica. Many of these spiders produce seven to eight distinct types of silks that are used in a variety of webs, ranging from silk-lined burrows in the ground to aerial orb-webs to the seemingly chaotic three-dimensional cobwebs." https://lnkd.in/dHWBg9g View in LinkedIn

REPEATED EVOLUTIONARY LOSSES. "Within the “RTA clade,” which is the sister group to orb-weaving spiders and contains half of all spider diversity, >90% of species richness is associated with repeated loss of cribellate silk and abandonment of prey capture webs." http://www.pnas.org/content/106/13/5229.full View in LinkedIn

SPIDER BEHAVIORAL SHIFTS. "Accompanying cribellum loss in both groups is a release from substrate-constrained webs, whether by aerially suspended webs, or by abandoning webs altogether. These behavioral shifts in silk and web production by spiders thus likely played a key role in the dramatic evolutionary success and ecological dominance of spiders as predators of insects." https://lnkd.in/db9PJGx View in LinkedIn