glp-1 adult lifespan at 25°C. One-day-old adults (1 day after L4 molt; time point circled in blue) are described in this paper as 'young' adults, whereas 6-day-old adults (6 days after L4 molt; time point circled in red) are described as 'aging' adults. One day after L4 molt was counted as 'day 1'; populations were maintained at 25°C from hatch. A total of eight replicate plates were monitored; three separate (in time) experiments were carried out. Additional details are given in the Materials and methods section (see text). Cuticular blisters were observed on 0 out of 100 randomly selected 1-day-old ('young') adults, but in 23 out of 100 randomly selected 6-day-old ('aging') adults; examples are shown in Additional data file 2. In Additional data file 2, hollow arrows point to tails without blisters, and solid arrows point to blisters. Mobility and feeding were markedly reduced beginning approximately on day 5, which was observable by inspection; the amount of OP50 eaten and distance traveled over 24 hours were also reduced. In 1-day-old ('young') adults, guts are cleared in about 30 min in M9 buffer; guts of 6-day-old ('aging') adults were not cleared, even after 2 hours.