Fine-scale Genetic Structure and Estimation of Gene Flow of the Japanese Brown Frog Rana japonica in a Satoyama Landscape on the Western Side of Inba Lake, Eastern Japan

Fine-scale genome-wide signature of Pleistocene glaciation in Thitarodes moths (Lepidoptera: Hepialidae), host of Ophiocordyceps fungus in the Hengduan Mountains

The Hengduan Mountains region is a biodiversity hotspot known for its topologically complex, deep valleys and high mountains. While landscape and glacial refugia have been evoked to explain patterns of inter-species divergence, the accumulation of intra-species (i.e. population level) genetic divergence across the mountain-valley landscape in this region has received less attention. We used genome-wide restriction site-associated DNA sequencing (RADseq) to reveal signatures of Pleistocene glaciation in populations of Thitarodes shambalaensis (Lepidoptera: Hepialidae), the host moth of parasitic Ophiocordyceps sinensis (Hypocreales: Ophiocordycipitaceae) or "caterpillar fungus" endemic to the glacier of eastern Mt. Gongga. We used moraine history along the glacier valleys to model the distribution and environmental barriers to gene flow across populations of T. shambalaensis. We found that moth populations separated by less than 10 km exhibited valley-based population genetic clustering and isolation-by-distance (IBD), while gene flow among populations was best explained by models using information about their distributions at the local last glacial maximum (LGM_L , 58 kya), not their contemporary distribution. Maximum likelihood lineage history among populations, and among subpopulations as little as 500 meters apart, recapitulated glaciation history across the landscape. We also found signals of isolated population expansion following the retreat of LGM_L glaciers. These results reveal the fine-scale, long-term historical influence of landscape and glaciation on the genetic structuring of populations of an endangered and economically important insect species. Similar mechanisms, given enough time and continued isolation, could explain the contribution of glacier refugia to the generation of species diversity among the Hengduan Mountains.

Designing participatory green area management and biodiversity conservation strategies in the era of population shrinkage: empirical analysis of multi-generational perceptions on Satoyama rare species in central Japan

Underuse, instead of overuse, is a potential threat to biodiversity in semi-natural areas, particularly in East Asia. Due to serious depopulation and aging trends in East Asia, including Japan, few people are being involved in managing green areas and conserving biodiversity. Depending on specific events and age groups that contribute to the experience, knowledge, and preferences of citizens, green area management and biodiversity conservation activities can be effectively conducted through strong collaborations between various stakeholders and generations. We aimed to understand the differences in the perceptions of citizens, belonging to different generations in the metropolitan Nagoya City, towards the Satoyama areas in Japan through an online survey. The status of Satoyama areas is reflected by the rare species of endangered category II in the Act on Conservation of Endangered Species of Wild Fauna and Flora. Analyzing the perceptions revealed gaps in the experience, knowledge, and preference between different age groups for various management and conservation activities. In addition to the intergenerational gaps, gaps between different household income levels and the duration of the activities were identified. The results indicated that reflecting upon the diverse interests among citizens and addressing the causes of the differences is necessary by integrating the differences for consensus building among different stakeholders belonging to different age and socio-economic groups.

Urbanization reduces gene flow but not genetic diversity of stream salamander populations in the New York City metropolitan area

Natural landscape heterogeneity and barriers resulting from urbanization can reduce genetic connectivity between populations. The evolutionary, demographic, and ecological effects of reduced connectivity may lead to population isolation and ultimately extinction. Alteration to the terrestrial and aquatic environment caused by urban influence can affect gene flow, specifically for stream salamanders who depend on both landscapes for survival and reproduction. To examine how urbanization affects a relatively common stream salamander species, we compared genetic connectivity of Eurycea bislineata (northern two-lined salamander) populations within and between streams in an urban, suburban, and rural habitat around the New York City (NYC) metropolitan area. We report reduced genetic connectivity between streams within the urban landscape found to correspond with potential barriers to gene flow, that is, areas with more dense urbanization (roadways, industrial buildings, and residential housing). The suburban populations also exhibited areas of reduced connectivity correlated with areas of greater human land use and greater connectivity within a preserve protected from development. Connectivity was relatively high among neighboring rural streams, but a major roadway corresponded with genetic breaks even though the habitat contained more connected green space overall. Despite greater human disturbance across the landscape, urban and suburban salamander populations maintained comparable levels of genetic diversity to their rural counterparts. Yet small effective population size in the urban habitats yielded a high probability of loss of heterozygosity due to genetic drift in the future. In conclusion, urbanization impacted connectivity among stream salamander populations where its continual influence may eventually hinder population persistence for this native species in urban habitats.