Effects of FSH on the population growth rate of females (ht), females with parthenogenetic eggs (hhp), and parthenogenetic eggs (hp) in the rotifer Brachionus calyciflorus. The concentration of FSH used was 0.4 mg/L. Population growth rate (r) is defined as offspring per female per day. Vertical lines on columns indicate standard deviations. Asterisks (*) represent significant differences with respect to control (p > 0.05). N = 6.