Abstracts (first author)
Genetic insights into the behavioural and morphological diversity of African mole-rats (family: Bathyergidae)
A principal constraint to have shaped many aspects of African mole-rat biology is their strictly subterranean lifestyle, with individuals rarely emerging above-ground. Linked to this lifestyle, their diet consists mostly of geophytes, the storage organs of plants, which has allowed mole-rats to occupy a range of climatically varied habitats across sub-Saharan Africa. Morphological adaptations include an elongated cylindrical body with shortened limbs, reduced eyes and external ears, and even hairlessness in the naked mole-rat (Heterocephalus glaber). Physiologically, mole-rats are adapted to a life in constant darkness, which may affect their circadian rhythms, and reduced oxygen levels (hypoxia), which may have allowed them to become insensitive to certain pain stimuli. Furthermore, for rodents, mole-rats are exceptionally long lived (~30 years). Social structure across the family ranges from solitary to eusociality, with sociality thought to have evolved multiple times. A subterranean lifestyle and similar social structures have convergently evolved in other divergent families within the Rodentia. All of these facts, coupled with the resource of the recently completed naked mole-rat genome, make this family a valuable group for diverse evolutionary studies.
To identify genes that have been targets of selection in this group, we are undertaking phylogenomic analyses of mole-rats using transcriptomes obtained from 8 ecologically diverse mole-rat species, including social and solitary species. We present our preliminary findings of comparative genetic analyses of candidate genes relating to some of the key adaptive traits, for example, those relating to sensory perception, locomotion and social behaviour, which have evolved within this family. With the aim of beginning to document and understand the genetic basis behind the numerous remarkable evolutionary adaptations shown by the members of this family of highly specialised hystricomorph rodents.