Multigenerational analysis of reproductive timing and life cycle parameters in the marine rotifer Brachionus plicatilis

Reproductive timing in organisms can influence reproductive success and longevity, yet its long-term effects remain underexplored. This study monitored the first- and last-born offspring of Brachionus plicatilis across five generations to examine the impact of breeding timing on fertility and longevity. The last-born group produced more offspring in the F1 and F2 generations. However, the first-born group produced more offspring from the F3 generation onward, with statistically significant differences observed in the F4 generation. Survival analysis indicated no differences up to the F3 generation. However, the post-reproductive period was significantly shorter in the last group compared to the first group in the F3 and F4 generations. These findings suggest that delayed breeding timing cumulatively reduces reproductive output and lifespan, though recovery may occur in the F5 generation. This study provides valuable insights into the generational effects of breeding timing and may inform reproductive strategies in similar species.