Inbreeding and inbreeding avoidance in the wild
Breeding with close relatives results in inbreeding depression, which commonly selects for inbreeding avoidance behaviours. However, there is a subset of species for which inbreeding is thought to be a regular part of the breeding system. One such species is the banded mongoose (see https://doi.org/10.1111/jzo.12466 for a review of inbreeding and its avoidance in cooperative societies).
Along with Dr Jenni Sanderson and Prof Mike Cant from the University of Exeter, we have shown that the banded mongoose Mungos mungo shows high levels of inbreeding in the wild, with around 9% of pups being the product of father-daughter or brother-sister matings (https://doi.org/10.1098/rsbl.2014.0898). Such frequent inbreeding probably occurs because both males and females stay in the same family group that they were born in, so have limited opportunities to mate with unrelated individuals (https://doi.org/10.1111/mec.12015). Despite this, banded mongooses do try to avoid inbreeding where possible. For example, males prefer to guard unrelated receptive females than related females during the mating season (https://doi.org/10.1111/mec.13253). In addition, females will sometimes risk their own lives to mate with males from rival groups during 'warfare' between neighbouring groups (https://doi.org/10.1093/beheco/arv095).
Our research on inbreeding and inbreeding avoidance in the banded mongoose continued with PhD student David Wells and MRes student Monil Khera working alongside Dr Hazel Nichols and Dr Joe Hoffman. We have investigated:
1.What are the drivers of inbreeding? We have found that females mate extra-group (to avoid inbreeding) when the probability of inbreeding within their own social group is high (https://doi.org/10.1093/beheco/araa105).
2.Is inbreeding avoided, and if so, how? Inbreeding levels within banded mongoose social groups are lower than would be expected under random mating. However, it is not clear how inbreeding is avoided; no simple behavioural forms of kin recognition fit the patterns observed. It is possible that they are able to use phenotype matching to avoid mating with close relatives as often as would be expected, or mating may in fact be random with regards to relatedness with early life mortality of inbred offspring leading to fewer inbred offspring entering the population.
3. What are consequences of inbreeding in a for cooperation? We found inbreeding depression for quality but not survival in pups and adults (with inbred adult males having particularly low reproductive success: https://doi.org/10.1111/mec.14570). We also found that care provided by parents and alloparents mitigates inbreeding depression for early survival. However, as adults, inbred individuals provide less care, reducing the amount of help available to the next generation. Our results suggest that inbred cooperative societies are rare in nature partly because the protective care that enables elevated levels of inbreeding can be reduced by inbreeding depression (https://doi.org/10.1111/ele.13578).
Along with Dr Jenni Sanderson and Prof Mike Cant from the University of Exeter, we have shown that the banded mongoose Mungos mungo shows high levels of inbreeding in the wild, with around 9% of pups being the product of father-daughter or brother-sister matings (https://doi.org/10.1098/rsbl.2014.0898). Such frequent inbreeding probably occurs because both males and females stay in the same family group that they were born in, so have limited opportunities to mate with unrelated individuals (https://doi.org/10.1111/mec.12015). Despite this, banded mongooses do try to avoid inbreeding where possible. For example, males prefer to guard unrelated receptive females than related females during the mating season (https://doi.org/10.1111/mec.13253). In addition, females will sometimes risk their own lives to mate with males from rival groups during 'warfare' between neighbouring groups (https://doi.org/10.1093/beheco/arv095).
Our research on inbreeding and inbreeding avoidance in the banded mongoose continued with PhD student David Wells and MRes student Monil Khera working alongside Dr Hazel Nichols and Dr Joe Hoffman. We have investigated:
1.What are the drivers of inbreeding? We have found that females mate extra-group (to avoid inbreeding) when the probability of inbreeding within their own social group is high (https://doi.org/10.1093/beheco/araa105).
2.Is inbreeding avoided, and if so, how? Inbreeding levels within banded mongoose social groups are lower than would be expected under random mating. However, it is not clear how inbreeding is avoided; no simple behavioural forms of kin recognition fit the patterns observed. It is possible that they are able to use phenotype matching to avoid mating with close relatives as often as would be expected, or mating may in fact be random with regards to relatedness with early life mortality of inbred offspring leading to fewer inbred offspring entering the population.
3. What are consequences of inbreeding in a for cooperation? We found inbreeding depression for quality but not survival in pups and adults (with inbred adult males having particularly low reproductive success: https://doi.org/10.1111/mec.14570). We also found that care provided by parents and alloparents mitigates inbreeding depression for early survival. However, as adults, inbred individuals provide less care, reducing the amount of help available to the next generation. Our results suggest that inbred cooperative societies are rare in nature partly because the protective care that enables elevated levels of inbreeding can be reduced by inbreeding depression (https://doi.org/10.1111/ele.13578).