Table 3.

Relative quantities (in mole %) of the organic LMM and inorganic phosphate in orb webs of the three species studied, as measured in the non-radioactive web collections

	Mean ± SEM1 (Range)2
	Araneus cavaticus	Argiope aurantia	Argiope trifasciata
	(means: N = 21)	(means: N = 7)	(means: N = 7)
	(ranges: N = 86)	(ranges: N = 102)	(ranges: N = 123)
putrescine	0.58 ± 0.067 (ND - 1.24)	ND (ND)	1.11 ± 0.157 (ND - 1.85)
choline	7.5 ± 0.94 (0.3 – 15.9)	4.2 ± 0.90 (0.2 – 7.4)	6.7 ± 1.28 (ND - 12.2)
GABamide	42.1 ± 1.05 (31.6 – 58.3)	52.6 ± 1.73 (47.6 – 70.8)	3.9 ± 0.93 (0.6 – 31.8)
N-acetylputrescine	3.13 ± 0.186 (ND - 6.60)	ND (ND)	32.8 ± 0.97 (14.7 – 43.0)
glycine betaine	0.37 ± 0.083 (ND - 2.42)	0.65 ± 0.227 (ND - 2.00)	2.4 ± 0.61 (ND - 5.0)
glycine	1.33 ± 0.157 (0.25 – 15.5)	2.5 ± 0.55 (0.7 – 19.9)	8.9 ± 0.55 (2.6 – 31.6)
alanine	0.45 ± 0.043 (ND - 2.76)	0.16 ± 0.030 (ND - 2.85)	2.82 ± 0.207 (0.18 – 6.06)
proline	0.76 ± 0.159 (ND - 8.83)	ND (ND - 1.65)	ND (ND)
taurine	ND (ND)	0.36 ± 0.048 (ND - 0.58)	0.32 ± 0.101 (ND - 0.80)
N-acetyltaurine	6.0 ± 0.50 (2.0 – 14.4)	12.7 ± 0.64 (2.5 – 17.2)	10.3 ± 1.25 (0.2 – 13.2)
isethionate	24.5 ± 0.75 (6.0 – 33.1)	8.8 ± 0.77 (1.5 – 11.6)	19.1 ± 1.71 (9.2 – 39.8)
H2PO4−	13.2 ± 0.37 (10.0 – 22.7)	18.1 ± 0.46 (8.7 – 22.8)	11.6 ± 0.28 (4.8 – 15.8)

All inorganic phosphorus was assumed to be present as H₂PO₄⁻.

ND, none detected by ¹H-NMR.

¹Means were calculated using only data from web collections 2–6 from Feeding groups and web collections 2–3 from Starving groups. This selection is somewhat arbitrary, but averages calculated from these data are probably closer to typical molar percentages in field-built webs than are means calculated using data from all web collections. Even so, some of the means presented (e.g. Cho) may still deviate substantially from average field-built webs.

²Ranges consider data from all non-radioactive web collections.