X-ray scattering analyses of the MA silks of different spider species has found that the micro-arrangement of silks from spiders in the Araneoidea clade are relatively conserved across the group . The mechanical properties of Araneoid spider MA silks, nonetheless, may vary considerably between species and individuals across environments and loading preconditions . For instance, silk spun by spiders walking along a surface is not as stiff as that spun by free falling spiders . Much of this variability is considered a consequence of changes in the friction acting on the silk as it exits the valve during spinning since this induces the amorphous region proteins to further self-align . The properties of the crystalline nanostructures can nonetheless also vary within individual spider silks across loading conditions. For example, spiders exposed to winds of different strength produce silks differing in nanocrystal density, which affects the ultimate strength of the fibers . Exposing spiders to strong wind induces silk extensibility and ultimate strength to change in the same direction . Simulations and experiments have shown that variations in glandular pH, salts and shear stress during spinning induce the poly-alanine residues to undergo α-helix→ β-sheet phase transitions, which enhances silk strength [47–50]. These types of phase transitions could explain the enhancement of ultimate strength from spiders exposed to high wind. Moreover, it has been shown that the additional enhancement of extensibility in the silks of spiders exposed to strong wind could be a consequence of spinning under a static load, since this induces the amorphous region proteins to move more freely relative to each other .