a C. elegans adult hermaphrodite

The C. elegans Lifecycle

In common with other nematodes, C. elegans develops through four larval stages (also called juveniles in some nematode literature) which are separated by moults. The lifecycle takes about 3 days at 20 deg.C, as illustrated below.

C. elegans also has an alternative L3 stage, known as the dauer ('enduring') stage. This stage is anadaptation to survival of extreme conditions (mainly lack of food) and is likely in the wild to be C. elegans' dispersal stage. Dauer larval development is induced by crowding (more congeneric nematodes make dauer entry more likely), lack of food (less food as a L1 makes dauer development more likely), temperature (higher temperatures make dauer development more likely) and genetics (there are many loci that control dauer development, and there is variation between wild strains in the propensity for dauer development).

The dauer L3 develops from a pre-dauer L2 (L2d) that has an altered metabolism (storing fats, and arresting gonad development). As a dauer, C. elegans can survive for many weeks, extending the nematodes' effective lifespan. On exposure to improved conditions (such as availability of food), the L3 dauer exits, and resumes development. The development of the gonad which usually has started in the L3, is arrested/delayed in dauer larvae, and subsequent to dauer exit, is accelerated so that the moult to adulthood coincides with reproductive maturity.

The C. elegans dauer has many similarities with the infective L3 larvae of many parasitic nematodes.

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