Sweeping the house clean: burrow architecture and seasonal digging activity in theEastAfrican root rat fromTanzania

Abstract

We investigated changes in burrow architecture and fractal dimension across seasons and between the sexes in the solitary East African root rat Tachyoryctes splendens over an entire calendar year. The basic burrow system comprised a main tunnel reticulating into foraging tunnels, a nest consisting of food store chamber, latrine and sleeping area, and a bolt hole. Main tunnel length was strongly affected by sex, and contrary to expectations, it was longer for females than for males (during both the dry and the wet seasons). The number and the length of foraging tunnels were affected by both sex and season, with females' burrows having more foraging tunnels than males in both the dry and the wet seasons. Females also had burrows with higher fractal dimension than males, while fractal dimension increased with burrow length for both sexes. We suggest that unlike the solitary bathyergid mole‐rats, male T. splendens do not construct larger burrows than females in the search for mates, but rather females have larger burrows with more foraging tunnels resulting from the increased need for provisioning of their young.

Craniometric Analysis of Ontogenetic Variation and Sexual Dimorphism in the East African Root Rat, Tachyoryctes Splendens (Rodentia: Spalacidae) From Tanzania.

“…The investment of energy for reproduction was evidenced on burrow architecture of T. splendens whereas female constructs more complex and reticulated burrow systems with more long foraging tunnels than males (Katandukila et al, 2014). The foraging efficiency of females T. splendens would expect to have large sizes than males but in contrast they are smaller-sized than males intimate that reproduction selectivity among females is less based on large size rather other criteria which is still unknown.…”

“…The increased ontogenetic variation from age class 2 in T. splendens indicate that growth pattern which favours adult-hood ecological selection and survival is prominent form young age before dispersal with age class 2 being the preparatory to dispersal. The T. splendens disperse at age class 3 when individual starts to carry on adult-hood tasks including burrow construction, independent foraging and defense (Katandukila et al, 2014). The significant ontogenetic variation at age class 3 and 4 than age class 5 imply that mean growth variation is more obvious on mid age classes than the oldest and youngest age classes as reported on other rodents (Zelditch, The cranial size of male T. splendens implies more utilization of energy for growth to attain large skeletal to support more muscles as adaptation to reproductive and ecological roles.…”

Pattern of ovulation in the East African root rat (Tachyoryctes splendens) from Tanzania: induced or spontaneous ovulator?

“…The root-rats were maintained at the Department of Zoology and Wildlife Conservation, University of Dar es Salaam (Republic of Tanzania) for three weeks prior to exportation to the Department of Zoology and Entomology, University of Pretoria, Republic of South Africa. Root-rats were housed singly since the species occurs solitary in the natural habitat (Katandukila et al 2014). …”

“…The root-rat is endemic to East and central Africa with a patchly distribution and particulary restricted to the highland savannah (Katandukila et al 2014;Kokiso and Bekele 2008;Jarvis and Sale 1971). It is a seasonal breeder possessing two breeding periods per year.…”

Comparative gastrointestinal morphology of Tachyoryctes splendens (Rüppell, 1835) and Heliophobius emini, (Noack, 1894) two species of East African mole‐rats

“…They have thick extrabuccal incisors that are a deep orange in color and do not possess a groove (Monadjem et al, ). Due to its fossorial lifestyle, T. splendens mainly feeds on underground storage organs of plants like roots, rhizomes, corms, tubers, and bulbs (Jarvis & Sale, ; Katandukila et al, ). In addition, T. splendens has been reported to occasionally venture to the surface, their hind quarters often remaining within the burrow, while ingesting relatively small amounts of aerial foliage (Jarvis, ; Jarvis & Sale, ; Nowak & Paradiso, ).…”