Evolution of the Grey-bellied pygmy mouse group: Highly structured molecular diversity with predictable geographic ranges but morphological crypsis.

The grey-bellied pygmy mouse (Mus triton) from the endemic African subgenus Nannomys is a widespread rodent species inhabiting the highlands of eastern and central Africa. Although it has long been considered as a single species, recent data has suggested the existence of a species complex. In order to evaluate the geographical structure and current taxonomy of M. triton, we analysed one mitochondrial and six nuclear genes from individuals covering most of its distribution range. Our analysis revealed the existence of at least five distinct genetic lineages with only marginal overlaps among their distributional ranges. Morphological comparisons, however, showed large overlaps in external body measurements and only a weak differentiation in skull form. Therefore, we suggest maintaining M. triton as a single taxon with pronounced intraspecific genetic structure. Divergence dating analysis placed the most recent common ancestor of the extant lineages of M. triton to the early Pleistocene (about 2.0 Ma). The phylogeographic structure of the species was likely shaped by Pleistocene climatic oscillations and the highly diverse topography of eastern Africa.

Asymmetric effect of environmental cost of forest rents in the Guinean forest-savanna mosaic: The Nigerian experience.

Several studies have identified deforestation as a major cause of environmental degradation, but little is known about the asymmetric effect of the environmental cost of forest rents. To fill this gap, our study uses the nonlinear autoregressive distributed lag (NARDL) model and asymmetric causality test to examine the environmental implication of forest rents in the Guinean Forest-Savanna Mosaic of Nigeria over the period 1990:Q1 to 2016:Q4. The empirical results show that forest rents increase CO2 emissions when the shock to forest rents is positive and decreases CO2 emissions when the shock to forest rents is negative. The results further show evidence of asymmetric effects of crop production, fossil fuel energy consumption, and economic growth on CO2 emissions. Moreover, the effects of both positive and negative shocks in economic growth are elastic, suggesting that CO2 emissions respond in a larger magnitude to a 1% positive or negative shock in economic growth. While the positive shock to crop production and economic growth stimulates CO2 emissions, their negative shocks dampen CO2 emissions. In addition, the positive (negative) shocks to fossil energy consumption exert upward (downward) pressure on CO2 emissions. Furthermore, the asymmetric causality test divulges that a positive change in forest rents causes a negative change in CO2 emissions and a negative change in forest rents causes a positive change in CO2 emissions. Based on these findings, the study recommends the need for policymakers to formulate sound policies to protect the forests and transit toward clean energy consumption to minimize energy-related CO2 emissions in the country.

Bonobo habituation in a forest-savanna mosaic habitat: influence of ape species, habitat type, and sociocultural context.

Habituation is the term used to describe acceptance by wild animals of a human observer as a neutral element in their environment. Among primates, the process takes from a few days for Galago spp. to several years for African apes. There are also intraspecies differences reflecting differences in habitat, home range, and ape-human relationship history. Here, we present the first study of the process of bonobo habituation in a fragmented habitat, a forest-savanna mosaic in the community-based conservation area led by the Congolese nongovernmental organization Mbou-Mon-Tour, Democratic Republic of the Congo. In this area, local people use the forest almost every day for traditional activities but avoid bonobos because of a traditional taboo. Because very few flight reactions were observed during habituation, we focused on quantitative parameters to assess the development of ape tolerance and of the tracking efficiency of observer teams. During the 18-month study period (May 2012-October 2013), 4043 h (319 days) were spent in the forest and bonobos were observed for a total of 405 h (196 contacts on 134 days). The average contact duration was stable over time (124 min), but the minimal distance during a contact decreased with habituation effort. Moreover, bonobo location and tracking efficiency, daily ratio of contact time to habituation effort, and the number of observations at ground level were positively correlated with habituation effort. Our observations suggest that bonobos become habituated relatively rapidly. These results are discussed in relation to the habitat type, ape species, and the local sociocultural context of villagers. The habituation process involves changes in ape behavior toward observers and also more complex interactions concerning the ecosystem, including the building of an efficient local team. Before starting a habituation process, knowledge of the human sociocultural context is essential to assess the balance between risks and benefits.