Fig. 1. Adult lifespan of cockroaches and spontaneous locomotion. (A) Blaberus discoidalis (N=73) and Periplaneta americana (N=31) cockroaches were placed in plastic containers immediately after molting to the adult stage. Containers were inspected weekly, and dead animals were counted and removed. Blaberus did not begin to die until week 36 post-adult molt, while Periplaneta showed a gradual dying-off. Periplaneta survived up to 64 weeks but Blaberus could live up to 80 weeks post-adult molt. 11% of the Blaberus discoidalis lived to 73 weeks after the adult molt. However, by week 61, 50% of the individuals were dead. (B) Spontaneous locomotion was defined as the total time spent walking, climbing or burrowing in a 10 min period. Spontaneous locomotion decreased significantly as adult cockroaches aged (regression analysis, slope=-3.4, r²=0.839, P<0.01).

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