Maternal age and offspring reproductive success

Researchers examine how maternal age influences the reproductive success of female offspring in marmots. Aging patterns vary across individuals of various species, but it is unclear how maternal age at the time of an individual’s birth influences the patterns. To measure the senescence and reproductive success of female offspring born to mothers of different ages, Svenja B. Kroeger, Julien G. A. Martin, and colleagues examined a population of wild yellow-bellied marmots living at two different elevations in the Colorado East River Valley. The data comprised of 656 observations made between 1967 and 2014 of 218 female marmots born to 97 different mothers. Compared with female offspring born to younger mothers, those born to older mothers had greater annual reproductive success and greater lifetime reproductive success. However, compared with high-elevation environments, in low-elevation environments the reproductive success of female offspring born to older mothers decreased faster with age. In harsh, high-elevation environments, female offspring born to older mothers tended to have shortened lifespans and died before reaching an age where senescent decreases are perceivable. Further, being born into a large litter negatively influenced the annual reproductive success of female offspring born to older mothers compared with those born to younger mothers. The findings suggest that maternal age, litter size, and environmental factors influence reproductive performance and senescence, according to the authors.

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Article #19-08551: “Older mothers produce more successful daughters,” by Svenja B. Kroeger, Daniel T. Blumstein, Kenneth B. Armitage, Jane M. Reid, and Julien G. A. Martin.

MEDIA CONTACTS: Svenja B. Kroeger, Norwegian Institute of Bioeconomy Research, Trondheim, NORWAY; tel: +47-90821036; email: <

[email protected]

>; Julien G. A. Martin, University of Ottawa, CANADA; tel: 613-562-5800 #2942, 873-688-0064; email: <

[email protected]

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