Table 2.

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

Araneus cavaticusArgiope aurantiaArgiope trifasciata
Mean1 ± s.e.m.Range2Mean1 ± s.e.m.Range2Mean ± s.e.m.1Range2
Putrescine0.58±0.067ND-1.24NDND1.11±0.157ND-1.85
Choline7.5±0.940.3-15.94.2±0.900.2-7.46.7±1.28ND-12.2
GABamide42.1±1.0531.6-58.352.6±1.7347.6-70.83.9±0.930.6-31.8
N-acetylputrescine3.13±0.186ND-6.60NDND32.8±0.9714.7-43.0
Glycine betaine0.37±0.083ND-2.420.65±0.227ND-2.002.4±0.61ND-5.0
Glycine1.33±0.1570.25-15.52.5±0.550.7-19.98.9±0.552.6-31.6
Alanine0.45±0.043ND-2.760.16±0.030ND-2.852.82±0.2070.18-6.06
Proline0.76±0.159ND-8.83NDND-1.65NDND
TaurineNDND0.36±0.048ND-0.580.32±0.101ND-0.80
N-acetyltaurine6.0±0.502.0-14.412.7±0.642.5-17.210.3±1.250.2-13.2
Isethionate24.5±0.756.0-33.18.8±0.771.5-11.619.1±1.719.2-39.8
H2PO4-13.2±0.3710.0-22.718.1±0.468.7-22.811.6±0.284.8-15.8
  • All inorganic phosphorus was assumed to be present as H2PO4-.

    ND, none detected by 1H-NMR.

    N values: Araneus cavaticus: means, N=21; ranges, N=86; Argiope aurantia: means, N=7; ranges, N=102; Argiope trifasciata: means, N=7; ranges, N=123.

  • 1 Means 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.

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