Inbreeding and inbreeding depression of early life traits in a cooperative mammal
Flower, Tom P. (Thomas Patrick); Sutcliffe, Robert L.; Samson, Jamie; Thavarajah, Natan K.; Clutton-Brock, Tim H.; Nielsen, Johanna F.; English, Sinead; Goodall-Copestake, Will P.; Wang, Jinliang; Walling, Craig A.; Bateman, Andrew W.; Kruuk, Loeske E.B.; Pemberton, Josephine M.
Mating between relatives often results in negative fitness consequences or inbreeding
depression. However, the expression of inbreeding in populations of wild cooperative
mammals and the effects of environmental, maternal and social factors on inbreeding
depression in these systems are currently not well understood. This study uses pedigree-based
inbreeding coefficients from a long-term study of meerkats (Suricata suricatta) in South
Africa to reveal that 44% of the population have detectably non-zero (F>0) inbreeding
coefficients. 15% of these inbred individuals were the result of moderate inbreeding
(F≥0.125), although such inbreeding events almost solely occurred when mating individuals
had no prior experience of each other. Inbreeding depression was evident for a range of traits:
pup mass at emergence from the natal burrow, hind-foot length, growth until independence
and juvenile survival. However, we found no evidence of significant inbreeding depression
for skull and forearm length or for pup survival. This research provides a rare investigation
into inbreeding in a cooperative mammal, revealing high levels of inbreeding, considerable
negative consequences and complex interactions with the social environment.