title: Extended longevity of reproductives appears to be common in Fukomys mole-rats (Rodentia, Bathyergidae).
abstract: African mole-rats (Bathyergidae, Rodentia) contain several social, cooperatively breeding species with low extrinsic mortality and unusually high longevity. All social bathyergids live in multigenerational families where reproduction is skewed towards a few breeding individuals. Most of their offspring remain as reproductively inactive "helpers" in their natal families, often for several years. This "reproductive subdivision" of mole-rat societies might be of interest for ageing research, as in at least one social bathyergid (Ansell's mole-rats Fukomys anselli), breeders have been shown to age significantly slower than non-breeders. These animals thus provide excellent conditions for studying the epigenetics of senescence by comparing divergent longevities within the same genotypes without the inescapable short-comings of inter-species comparisons. It has been claimed that many if not all social mole-rat species may have evolved similar ageing patterns, too. However, this remains unclear on account of the scarcity of reliable datasets on the subject. We therefore analyzed a 20-year breeding record of Giant mole-rats Fukomys mechowii, another social bathyergid species. We found that breeders indeed lived significantly longer than helpers (ca. 1.5-2.2fold depending on the sex), irrespective of social rank or other potentially confounding factors. Considering the phylogenetic positions of F. mechowii and F. anselli and unpublished data on a third Fukomys-species (F. damarensis) showing essentially the same pattern, it seems probable that the reversal of the classic trade-off between somatic maintenance and sexual reproduction is characteristic of the whole genus and hence of the vast majority of social mole-rats.
authors.affiliation: Department of General Zoology, Institute of Biology, University of Duisburg-Essen, Essen, Germany. philip.dammann@uk-essen.de
authors.forename: Philip
authors.initials: P
authors.lastname: Dammann
authors.forename: Radim
authors.initials: R
authors.lastname: Šumbera
authors.forename: Christina
authors.initials: C
authors.lastname: Massmann
authors.forename: André
authors.initials: A
authors.lastname: Scherag
authors.forename: Hynek
authors.initials: H
authors.lastname: Burda
mesh_terms: D000818:Animals; D044127:Epigenesis, Genetic; D005260:Female; D008136:Longevity; D008297:Male; D019577:Mole Rats / Q000145:classification / Q000235:genetics / Q000502:physiology*; D010802:Phylogeny; D012098:Reproduction