Starve and survive: stress tolerance and life-history traits of a bdelloid rotifer

1. Bdelloid rotifers occur in unstable habitats, such as moss, lichens and temporary pools, where conditions change unpredictably and dramatically. Their ability to survive in such habitats could be related to their physiological ability to enter metabolic stasis in response to severe environmental stress. We tested the response of a bdelloid species ( Macrotrachela quadricornifera Milne, 1886) to prolonged starvation by evaluating survival and fecundity once food was resupplied on a regular basis. 2. Animals were starved for different durations (20, 40, 60 days) and all survivors resumed reproduction. Life-history parameters of the 20-day starvation group subsequent to the resumption of normal feeding were studied. 3. From resumption of normal feeding, mean longevity and age-specific traits of starved rotifers were the same as those of the fed rotifers. No reduction of lifetime fecundity was found in the bdelloids that experienced starvation, suggesting a time shift of the effective ‘age’ of the starved rotifers. 4. The response of the rotifer to starvation is similar to that induced by drought. The presence of a previously undocumented form of dormancy is hypothesized.