In summary, we found that the MA silk properties of five species of Araneoid spiders varied in response to similar variations in protein intake. Stronger and tougher silks with greater crystallinity and amorphous region nanostructural alignments were found for protein fed P. graeffei and N. plumipes which contrasted with the findings for A. keyserlingi and those reported previously for protein fed/deprived N. pilipes . The properties and nanostructures of L. hasselti’s MA silks were unaffected by nutrient deprivation. Our analyses suggested that variations in MaSp1: MaSp2 expression were largely ineffectual over amino acid compositions. Proline and alanine composition and the crystalline and amorphous nanostructures significantly varied in all species with the exception of Latrodectus hasselti, all with subsequent effects on mechanical properties. We uncovered additional unexpected and novel findings regarding the mechanisms inducing variations at different levels in different spiders. For instance, MaSp2 genes were not as strongly regulated as we might have predicted under the current MaSp model when protein intake changed in A. keyserlingi, N. plumipes or P. graeffei. Rather MaSp1 was more likely to be up or downregulated in these spiders. Our modelling showed that variations in silk strength were associated with variations in crystallinity and the size, length and alignment of the crystalline and non-crystalline proteins independent of expressions of the MaSp genes. Extensibility and toughness on the other hand were driven by variations in the crystalline, amorphous and lamellar region nanostructural alignments, which were largely disassociated from MaSp expression.