Anhydrobiosis of Adineta ricciae: costs and benefits

To study the effect of anhydrobiosis on the rotifer life cycle, we dried a bdelloid species. Adineta riceicte. and determined the life-history traits of 1) the rehydrated animals and 2) the offspring, produced after a period of dormancy. In the first experiment, a cohort was dried when 8-days-old. kept dry for 7 days and then rehydrated. Recovery was about 75%. The recovered rotifers had similar longevity and significantly higher fecundity than the hydrated controls. The time spent dry was completely disregarded by the anhydroblotic rotifers, as predicted by the 'Sleeping Beauty' model. In the second experiment. we recorded the life-history traits of the orthoclones produced by recovered mothers aged 11 days, and IS days. These orthoclones were coupled to controls that had been established from hydrated mothers aged 11 days and 18 days. The orthoclones produced after dormancy had significantly higher fecundity and longevity than the controls of same maternal age. Maternal age had a marked effect on the life-history traits of the orthoclones of both lines, causing the same loss of fitness in both.