Table 2.

Computed features of viscous threads

SpeciesNPrimary droplet volume (μm3)Secondary droplet volume (μm3)Secondary to primary droplet ratioPrimary droplet shape (μm)Proportion of waterFlattened droplet area (μm2 mm–2)Residual extensibility
Argiope aurantia 559287±114041073±3641.14±0.1924.450.49±0.03 (3)63363±113856.33±0.49
Araneus marmoreus 1079730±137083264±725 (7)0.69±0.1522.440.48±0.11 (4)128561±153796.53±0.62
Argiope trifasciata 1112005±21501314±2631.41±0.2917.150.41±0.15 (3)30834±27476.41±0.68
Araneus bicentenarius 643234±136942353±10170.79±0.1215.330.63±0.12 (3)63117±82169.06±1.06
Larinioides cornutus 420264±940912021±69940.58±0.1414.130.29±0.08 (4)34513±19353.97±0.50
Verrucosa arenata 56055±694243±162 (4)0.33±0.188.650.39±0.06 (3)27084±54563.53±0.33
Araneus pegnia 915124±36561340±1176 (3)0.08±0.0413.150.66±0.05 (5)120726±5554 (7)6.74±0.82
Micrathena gracilis 57510±1510453±129 (4)0.65±0.209.710.43±0.09 (4)100813±386058.69±0.60
Theridiosoma gemmosum 51249±746387±2840.81±0.394.490.53±0.15 (2)8743±23323.82±0.34
Micrathena sagittata 54622±766286±1350.72±0.138.370.32±0.11 (4)131080±97935.39±0.18
Tetragnatha elongata 45846±2332161±113 (3)0.60±0.259.930.03±0.02 (3)26665±82935.13±0.98
Metepeira labyrinthea 83014±632203±1241.05±0.218.420.66±0.07 (4)31117±39466.89±0.64
Meta ovalis 8896±14637±160.39±0.094.680.57±0.08 (5)12989±2071 (7)4.53±0.27
Leucauge venusta 10698±18639±7 (7)0.35±0.114.740.70±0.08 (5)15105±2314 (8)4.98±0.19
Cyclosa turbinata 9608±14974±100.85±0.074.430.57±0.18 (4)19679±4114 (8)5.63±0.38
Mangora maculata 640±713±3 (4)0.29±0.141.090.68±0.06 (5)390±2224.93±0.28
  • Means ± 1 s.e. Numbers in parentheses give the sample size if less than that listed in the second column