We weighed all of the silk samples designated for amino acid composition analysis to the nearest 0.001 mg on an electronic balance (Pioneer PA214C, Ohaus, Pine Brook NJ, USA), before submergence in 99% hexoflouro-isopropanol solvent (500 μl of per mg of silk) within 1 ml Eppendorf tubes. The samples were then hydrolyzed in 6 mol l-1 HCl for 24 h at 115°C. Molar percentage compositions of glutamine, serine, proline, glycine, and alanine, the amino acids representing ~90% of the total amino acids in the MA silks of most spiders , determined using an Alliance Systems (Waters, Rydalmere NSW, Australia) high performance liquid chromatography column  at the Australian Proteomic Analysis Facility, Sydney.