Background and aim: African Greater Cane (ACG) rat populations are widely distributed across Africa but the ancestral origin of populations inhabiting different geographical regions is unknown. There is currently no information available on the genetic differentiation of these populations resulting from long-time geographical isolation, environmental and anthropogenic pressures they face in each region. This limits our ability to understand potential speciation processes in AGC and their implications for their conservation and of other small wild mammals exposed to similar ecological conditions in the savannah biomes in Africa. Methods: We analyzed mitochondrial genes targeting the D-loop region of AGC samples from two blocks of the Eastern Arc Mountains in Tanzania (eastern), three agro-ecological zones in Ghana (western) and four sites in South Africa (southern) to characterize the phylogeographical patterns of the species. Results: AGC populations from Tanzania revealed higher haplotype diversity than those from the two other régions. Analysis of variance (AMOVA) revealed higher genetic variations within than between populations in all geographic regions. Demographic history analysis revealed a negative and significant Tajima’s D for a single southern African population as well as close relatedness with the Eastern Africa populations, suggesting a common ancestral origin. Conclusion: This is the first study to compare maternal lineages of AGC populations from eastern, western and southern Africa and provides a basis for future genetic studies of the species, its evolutionary ecology and the conservation of these populations across their range. Conservation implications: Evidence of recent population size expansion underpinned by high genetic diversity observed in the Uluguru urban (Tanzania) Guinea savannah (Ghana) and Kwazulu Natal (South Africa) populations suggest that the AGC populations are not currently threatened, consistent with the current IUCN status. Also, the distinct haplotypes observed in each region suggest that the populations can be managed as meta-populations, thus providing opportunities for potential local game-farming programs.

Evolutionary information on the greater cane rat (Thryonomys swinderianus) in the Eastern and Southern African regions is scarce, making population management and conservation of the species challenging. We studied T. swinderianus populations from two spatially isolated Eastern Arc Mountains in Tanzania to link molecular and geometric–morphological evidence to characterize these populations’ diversity. Fecal samples (n = 50) and skulls (n = 99) of T. swinderianus were collected from Udzungwa (north and south) and Uluguru mountains (urban and rural sites) and analyzed using molecular and geomorphometry techniques. Molecular analysis grouped the population into three distinct clades based on the location where the samples were collected, while the morphometric method was not able to distinctively separate the populations. Both methods revealed that the population obeyed the isolation by distance model with higher genetic distance between the Udzungwa and Uluguru populations and lower distance between Uluguru urban and rural populations. Both Mahalanobis and Procrustes distances in skull landmarks between the Udzungwa and Uluguru populations were significantly higher across the dorsal, ventral, and lateral views of the skulls, suggesting strongly that molecular and morphometric methods applied together can be useful in characterizing the population traits of the least known species. Our study suggests genetic and morphometric methods could complement each other in understanding the evolutionary biology and within-species diversity of vertebrate species that do not exhibit strong intra-species differentiation.

The African Greater Cane rat (AGC) populations in East and West Africa bear single ancestral origin. However, to date, information is lacking on their genetic differentiation due to long-time geographical isolation and the environmental and anthropogenic pressures the populations face in each region. This gap limits our ability to understanding potential speciation in these populations. We analysed the genetic sequences of cane rat samples from Tanzania and Ghana to characterize the phylogeographic patterns of the two populations based on the mt-DNA. The D-loop sequences used comprised samples collected from two Eastern Arc Mountains in Tanzania and three agro-ecological zones in Ghana. We found a high nucleotide diversity in AGC population from Tanzania (0.022±0.003) and low nucleotide diversity in Ghana (0.013±0.003). Analysis of Molecular variance (AMOVA) showed significant genetic differentiation between AGC population from Tanzania and Ghana (Fst=0.85938, p<0.00001). Further, analysing the genetic differentiation, we found high variation by 85.94% in AGC populations between Tanzania and Ghana and low variation (14.06%) within any AGC population at individual region. Reconstructing past history of the population in each region based on the neutrality test revealed a positive (0.006) Harpending’s raggedness index for Tanzania and negative (-0.009) for Ghana. Also, Tajima’s D was negative (-0.798) for Tanzania and positive (0.041) for Ghana, indicating that the population of Tanzania is increasing while the Ghanaian is decreasing. This is the first study to compare maternal lineages of the AGC population from two regions in Africa, and provides a basis for future studies.

Small mammals, the most species-rich group in the class Mammalia, form the prey base for meso-predators, hence knowledge of their populations is an important management tool. This study aimed to provide an updated inventory and conservation status assessment of small mammals in Mikumi National Park (MINAPA) and Udzungwa Mountains National Parks (UMNP), Tanzania, from surveys conducted in 2020 - 2021. Small mammals were captured using live traps. A total of 148 individuals were recorded, with murids being the most dominant group and Acomys wilsoni the most trapped species. Species diversity and trap success were slightly higher in MINAPA compared to UMNP. In addition, camera traps recorded the grey-faced sengi, Rhynchocyon udzungwensis, an endemic and vulnerable species of Udzungwa. These findings provide current baseline data on small mammals in protected areas, demonstrating their ecological significance. We suggest that this often-overlooked faunal diversity might open potential for targeted eco-tourism.