Fig. 2.

Duration of development for female P. metricus. Duration was measured from cocoon spinning to emergence in the field (a) and from cocoon spinning (in the field) to adult molt in the laboratory (b) for P. metrius females reared by a solitary foundress (F-R) or by nestmate workers (W-R). Bars are means with standard errors. Developmental stages for laboratory reared specimens are defined in Fig. 2. Mean temperatures (°C ± SE) during rearing were: F-R field = 23.0 ± 0.5; W-R field = 26.1 ± 0.6; F-R lab = 24.4 ± 0.4; W-R lab = 24.0 ± 0.1.