The children of older mothers do not fare as well as those of younger mothers, in humans and many other species. They are not as strong, or they do not live as long. A longstanding mystery is why evolution would maintain this maternal effect in so many species since these late-born offspring are less fit to survive and reproduce.
In new research in rotifers (microscopic invertebrates), scientists tested the evolutionary fitness of older-mother offspring in various real and simulated environments, including the relative luxury of laboratory culture, under threat of predation in the wild, or with reduced food supply. They proved that this outcome of older maternal age, called maternal effect senescence, does decrease the evolutionary fitness of the offspring in all conditions, primarily through reduced pregnancy during their peak reproductive period. They also suggest an evolutionary mechanism for why this may occur. The research, led by Kristin Gribble of the Marine Biological Laboratory and Christina Hernández of Woods Hole Oceanographic Institution, is published this week in Proceedings of the National Academy of Sciences.
Health News – July 03, 2020
Source – Science Daily.
Health Magazine – July 2020, Vol-01, Page-04