We collected silk from the remaining 75 spiders [16 A. keyerslingi (8 each from the N and P treatment), 18 E. transmarina (9 N and 9 P), 15 L. hasselti (7 N and 8 P), 10 N. plumipes (4 N and 6 P) and 16 P. graeffei (8 N and 8 P)] to determine their amino acid compositions. We wrapped the silk threads around a glass tube connected to the electronic spool spun at 1m min-1for ~1–2 h. This approximated the collection of the store of silk from the spider’s glands, so any variations in amino acid composition within individual threads were accounted for. All silks were extracted under controlled temperature (~25°C) and humidity (~50% R.H.) in still air, so reeling speed and post-spin environment did not influence the subsequent chemical or mechanical property measurements.