Japanese Islands Research Articles

Performance Analysis of a Strong Constraint 4DVar and 4DEnVar on Regional Ionosphere Imaging

AbstractData assimilation (DA) techniques have recently gained traction in the ionospheric community, particularly at regional operational centers where more precise data are becoming prevalent. At center stage is the argument over which technique or scheme merits realization. At 4DSpace, we have in‐house developed and assessed the performance of two regional flavors of short‐term forecast strong constraint four‐dimensional (4D, space and time) variational (SC4DVar) DA schemes; the orthodox incremental (SC4DVar‐Inc) and ensemble‐based (SC4DEnVar) approach. SC4DVar‐Inc is bottled‐necked by expensive Tangent Linear Models (TLMs) and model Ad‐joints (MAs), while SC4DEnVar design mitigates these limitations. Both schemes initialize from the same background (IRI‐2016), and electron densities forward propagated (30‐min) by a Gauss Markov filter‐ the densities take on a log‐normal distribution to assert the mandatory ionosphere density positive definiteness. Preliminary assimilation is performed only with ubiquitous Global Navigation Satellite System observables from ground‐based receivers, with a focus on moderately stable mid‐latitudes, specifically the Japanese archipelago and neighboring areas. Using a simulation analysis, we find that under model space localization, 30 member Ensembles are sufficient for regional SC4DEnVar. Verification of reconstructions is with independent observations from ground‐based ionosonde and satellite radio occultations: the performance of both schemes is fairly adequate during the quiet period when the background has a better estimation of the hmF2. SC4DVar‐Inc is slightly better over areas densely populated with measurements, but SC4DEnVar estimates the overall 3D ionosphere picture better, particularly in remote areas and during severe conditions. These results warrant SC4DEnVar as a better candidate for precise short‐time regional forecasts.

Discovery of a new population of the endangered giant water bug Kirkaldyia deyrolli (Heteroptera: Belostomatidae) in Kyushu and evaluation of their genetic structure

AbstractThe giant water bug Kirkaldyia deyrolli is one of the most well‐known endangered aquatic insects in Japan. The population of this species in Kyushu, one of the four major islands of the Japanese Archipelago, is extremely limited. In the present study, we identified a new population of K. deyrolli and undertook population genetic structure analyses based on genome‐wide nuclear DNA single nucleotide polymorphisms (SNPs). We collected samples using a nonlethal sampling method and obtained 59,279 SNPs. The results of our study confirm that sufficient SNP data for population genetic structure analysis can be obtained through nonlethal sampling. We determined that the newly identified population is genetically differentiated from a previously identified population on Kyushu. Therefore, this population is considered highly important for the conservation of K. deyrolli in Kyushu.

Comparative study on cavernous weathering features formed by coastal processes and acidic alteration: Implications for rounded pits on Martian rocks

Surface images taken by rovers and landers show the existence of rounded pits with diameter of centimeters on Martian rock surfaces. These pits seem to be similar to terrestrial cavernous weathering features, generated by salt weathering (e.g., alveoli), or by stream flow erosion (e.g., potholes), found near coastal areas. Alternatively, if the weathered rocks contained carbonate minerals, the pits might have been formed by acidic weathering. Here, we compare geomorphology of cavernous weathering features formed by coastal processes on Earth and by laboratory experiments simulating acidic weathering of carbonate. Our field observations for coastal areas of the Japanese islands show that a high cavity number density and small cavities characterize cavernous features formed by salt weathering as compared with those formed by stream flow. Our experimental results show that acidic weathering can generate cavernous features, with high number densities and small diameters. Based on principal component analysis, cavernous weathering features formed by salt weathering, stream flow, and acidic alteration can be distinguished mainly by the number density and diameter. By applying our approach to Martian rocks, we find that the morphological characteristics of rounded pits on Jezero Crater rocks are different from the above cavernous weathering features, and that the Martian pits are categorized as being intermediate between cavernous features formed by salt weathering and acidic weathering. If the pits on Jezero Crater rocks were formed by salt weathering, salt weathering on Mars could have been less effective (possibly, due to a difference in water salinity or salt composition) than those found in coastal areas of Earth. Alternatively, these Martian pits might be formed by other processes (e.g., vesicles in volcanic breccia, eolian processes, or freeze-thaw cycles of porewater).

Evolutionary history of a cold-adapted limnephilid caddisfly: Effects of climate change and topography on genetic structure

The distribution of organisms is influenced by complex factors such as the phylogenetic evolutionary histories of species, the physiological and ecological characteristics of organisms, climate, and geographical and geohistorical features. In this study, we focused on a caddisfly, Asynarchus sachalinensis (Trichoptera: Limnephilidae), which has adapted to cold habitats. From phylogeographic analyses based on the mitochondrial DNA (mtDNA) cytochrome c oxidase subunit I (COI) and 16S rRNA regions and the nuclear DNA (nDNA) 18S rRNA, 28S rRNA, carbamoyl-phosphate synthetase (CAD), elongation factor-1 alpha (EF1-α), and RNA polymerase II (POLII) regions, two distinct genetic clades were detected. Clade I was shown to be widely distributed from Sakhalin to Honshu, whereas Clade II was only distributed within Honshu. The distributions of these clades overlapped in Honshu. The habitats were located at relatively lower altitudes for Clade I and higher altitudes for Clade II. The divergence time of these clades was estimated to be during the Pleistocene, indicating that repeated climatic changes facilitated distributional shifts. Haplotype network and demographic analyses based on the mtDNA COI region showed contrasting genetic structures in the two clades. It was indicated that the population sizes of Clade I had expanded rapidly in a recent period, whereas Clade II had maintained stable population sizes. The habitats of Clade II were typically isolated and scattered at high altitudes, resulting in restricted migration and dispersal because of their discontinuous “Sky Island” habitats. The habitats of Clade I were located at relatively low altitudes, and it was assumed that the populations were continuous, which resulted in a higher frequency of migration and dispersal between populations. Thus, differences in the spatial scale of the adapted habitats of each clade may have resulted in different patterns of population connectivity and fragmentation associated with repeated climatic changes during the Pleistocene. Our study provided new insight into the distributional patterns of cold-adapted aquatic insects in the Japanese Archipelago. Furthermore, the distributional shifts predicted by ecological niche modeling under future climatic change conditions were different for each clade. Therefore, different principles are required in the assessment of each clade to predict temporal changes in their distributions.

Fine-scale phylogeography of the Japanese Genji firefly

Abstract The Japanese Archipelago consists of four major islands and numerous small islands. The Goto Islands are located near Kyushu, a major island in the Japanese Archipelago. We have previously reported that the population of the Japanese Genji firefly, Nipponoluciola cruciata, inhabiting the Goto Islands displays a unique flashing pattern that is used for pre-mating communication between males and females, indicating the possibility of genetic isolation of the Goto Islands population from neighbouring N. cruciata populations. In this study, we aimed to elucidate the gene flow between the Goto Islands N. cruciata population and its neighbouring island populations by molecular phylogenetic analyses based on the mitochondrial DNA regions of cytochrome c oxidase subunit II and ND5, also coupled to genome-wide analysis of nuclear DNA single nucleotide polymorphisms. Our results suggested that the Goto Islands N. cruciata population is genetically isolated from other populations of this species. Nuclear DNA-based population analyses indicated gene flow between the populations inhabiting the Kyushu and Iki Islands, situated at a distance approximately equal to that between the Goto and Kyushu Islands. Therefore, the genetic isolation of the Goto Islands N. cruciata population is largely affected by flashing pattern behaviour, underlining an ongoing speciation process.

Demic Diffusion of the Yayoi People in the Japanese Archipelago

The present study examines the 3-dimensional data of human crania from the Yayoi period (800 BC to AD 250) of the Japanese archipelago by geometric morphometrics to investigate demic diffusion patterns. This is the first study on the Yayoi crania using their 3D data and geometric morphometrics with a much larger number of skeletal remains outside of the Kyushu regions than previous studies. The comparative results between the Jōmon and Yayoi samples show that the Yayoi people not only in the eastern parts but also in the western parts of the archipelago are significantly different from the final Jōmon people and the Yayoi people were not strongly affected by the Jōmon people. A relatively gradual geological cline is also found among the Yayoi population, suggesting that the immigrants from the continental East Asia moved from the western parts to the eastern parts of the archipelago though the causes of the morphological changes are unclear.

Molecular phylogeny and taxonomy of Hosta (Asparagaceae) on Shikoku Island, Japan, including five new species, one new subspecies, and two new status assignments.

Japan has 16 native species of the genus Hosta Tratt. (Asparagaceae). A recent study on Hosta based on field surveys and molecular phylogenetic analyses resulted in the discovery of six unknown taxa in Kochi Prefecture, Shikoku Island, southwestern Japan. We aimed to identify these unknown taxa. Therefore, we constructed a finely resolved phylogeny for 320 Hosta samples collected from the Honshu, Shikoku, and Kyushu Islands using multiplex inter-simple sequence repeat genotyping by sequencing (MIG-seq). Based on this phylogenetic analysis and related morphological observations, we describe five new species, H.longipedicellatasp. nov., H.minazukiflorasp. nov., H.polyneuronoidessp. nov., H.samukazemontanasp. nov., and H.takiminazukiflorasp. nov. and one new subspecies, H.takiminazukiflorasubsp.grandissubsp. nov. In addition, we propose two new status assignments, H.tardivasubsp.densinerviacomb. and stat. nov. and H.scabrinerviastat. nov. We also propose classifying H.kikutiivar.tosana as a species, H.tosana. Further studies that combine MIG-seq with careful morphological observations are needed for Hosta plants on all Japanese islands, which may result in the discovery of even more undescribed species.

Morphological description of the glochidia of Buldowskia suifunica (Bivalvia: Unionidae).

Freshwater mussels of the genus Buldowskia (Bivalvia, Unionidae) are distributed from the Amur River basin in Russia and China southward to the Korean Peninsula and some Japanese islands. This work is an integrative morphological study of Buldowskia suifunica glochidia from locations in the Primorsky Territory, the Russian Far East. Glochidia of B. suifunica, taken from the same gill have asynchronous development. The external and internal morphology of its shell has been characterized. The morphology of its sensory system, within three stages of larval development (immature, intermediate and mature glochidia), consists of hair cells as well as nonhair cells. Their muscle system is composed of massive adductor and minor muscle bundles. The FMRFamid-ergic nervous system turned out to be a complex system includes basal cells (neurons), their neurites and anterior neurons. FMRFamide and tubulin was found in all neurons. Glochidia of B. suifunica have only four 5-HT-lir neurons. We concluded that B. suifunica glochidial nervous system differs from those of the larval systems of planktotrophic marine mollusks.

Deformation Anomalies Accompanying Tsunami Origins near the Japanese Islands

In the paper, we analyze laser strainmeter data for the period from 2014 to 2022 to identify deformation anomalies that led to the generation of tsunamis in the area of the Japanese Islands. It is impossible to determine the main characteristics of a tsunami from the deformation anomaly registered by the laser strainmeter, but it is possible to calculate the seabed displacement in the epicenter of a tsunami formation, which causes the tsunami. We have established that the relationship between the registered deformation anomalies and the seabed displacement in the tsunami source in the area of the Japanese Islands is similar to the same relationships found in other regions of the Earth (Indonesia, Latin America, and the West Coast of North America). This result allows us to assert that such a relationship should be typical of any region of the Earth. The obtained results are aimed at solving the problem of reliable short-term tsunami forecasting, which allows for the avoidance of false alarms that lead to significant socio-economic damage.

Phylogeography of an insect inhabiting ‘Sky Islands’: the relationships among genetic structures and geographical characteristics, geohistorical characteristics, and cyclical climate changes

Abstract When gene flow has been restricted between populations, the genetic structure of such species often reflects geohistory and climate changes. Populations of species inhabiting high-altitude regions, known as ‘Sky Islands’, are isolated and exhibit restricted gene flow, so they often have habitat-specific genetic structures that correspond to their surrounding geographical structures. Here we focus on a limnephilid caddisfly, Rivulophilus sakaii, which inhabits the alpine zone of Japan. Phylogenetic analyses were conducted based on the mtDNA COI and 16S rRNA regions, and the nDNA 18S rRNA, 28S rRNA, CAD, EF1-α, and POL-II regions; the results indicated three phylogeographically differentiated intraspecific lineages. Haplotype network and demographic analyses based on the mtDNA COI region suggested the size of the respective isolated populations has stabilized. This suggests that mountain formation in the Japanese Archipelago due to volcanic activity has resulted in barriers to migration and dispersal between high-altitude aquatic insect populations. This was inferred to be an effect of Quaternary climate changes that caused vertical distributional shifts following mountain formation, resulting in repeated connection and fragmentation of the populations. This is important supporting information with regard to discussing the effects and functions of geohistory and climatic changes on the phylogenetic evolution of organisms presently inhabiting interglacial ‘Sky Islands’.

Phytosociological characteristics of Betula davurica–Quercus crispula forests in Japan based on a comparison with summergreen broad-leaved forests in Northeast Asia

Betula davurica and deciduous Quercus forests are among the principal forest types in Northeast Asia. They are found throughout continental Northeast Asia and in some mountainous regions of Central Honshu and eastern Hokkaido in the Japanese Archipelago. B. davurica–Quercus crispula forests in Japan are significant for understanding the phytogeography of Japan and Northeast Asia. However, their relationships with B. davurica–Quercus mongolica forests in continental Northeast Asia remain poorly understood. We compared the species composition of B. davurica–Q. crispula forests of Japan, with those of Q. crispula dominant forests and B. davurica–Q. mongolica forests using phytosociological methods. The results suggested that B. davurica–Q. crispula forests of Japan had a significant number of species common to the order Lespedezo bicoloris–Quercetalia mongolicae and the class Querco mongolicae–Betuletea davuricae in continental Northeast Asia than in other associations in Japan. Furthermore, our results showed that associations between B. davurica and Q. crispula forests in Central Honshu and Hokkaido are related to different orders in continental Northeast Asia. The relations of the associations between Japan and the continent are considered to have been caused by the environmental similarities, the histories of taxa, and the changes in vegetation distribution.

Trans-Japan Sea land-bridge disjunction: A case of vicariance in the subterranean genus Nipponasellus (Crustacea, Isopoda, Asellidae) in a large-scale biogeographical context.

This study examines nineteen phreatobiological hand pump samples collected in 20092010 in three separate areas of salmon river basins in the southern part of Primorye, in the Far East of Russia. For the first time, faunal groundwater patterns were assessed for the rivers of Eastern Manchuria, the Ussury River Basin and the rivers of the south-western slope of Sikhote Alin. A total of 164 species (including 32 stygobionts) belonging to the phyla Annelida, Mollusca and Arthropoda are first records of groundwater animals, and two of the stygobionts are described below as new species for Science. Nipponasellus sudzukhensis spec. nov. and N. matsumotoi spec. nov. are described and illustrated, and their taxonomic affinities with congeners are discussed. The morphology of male pleopod 2 of the genus Nipponasellus is re-examined using scanning electron microscopy (SEM), which revealed fine details of the pleopodal structures. The two new continental species of Nipponasellus were characterised by a distinct cannula completely immersed in ctenoid cuticular scales and the absence of a labial spur. Informal macrogroups were proposed based on the structure of the appendix masculina and an analysis of family distribution. The results of cladistic analyses revealed relationships between the proposed groups, but phylogenetic relationships within the Caecidotea-Proasellus group remain challenging. Common diagnostic characters of Nipponasellus showed that the group occupies an independent position close to the Caecidotea-Proasellus group rather than the Asellus-pattern sensu Magniez. Revised diagnosis for the genus Nipponasellus is given, including the two new species and the five previously described ones. The species diversity of East Asian stygobiotic asellid isopods is briefly reviewed to infer a biogeographic distribution pattern that emphasises the strict endemicity of members of the genus Nipponasellus. The intracontinental separation between continental Far East Asia and the Japanese archipelago highlights the biogeographic importance of the land-bridge in the Oligocene and raises questions about hypotheses explaining the (disjunct) distribution in East Asia, together with the circumstances preceding an ancient colonisation of the region.

Phylogeography and genetic diversity of the Japanese mud shrimp Upogebiamajor (Crustacea, Decapoda, Upogebiidae): Natural or anthropogenic dispersal?

Upogebiamajor (De Haan, 1841) is known for forming huge burrows in sandy, intertidal areas that can extend to depths of over 2 m. Despite its widespread distribution in East Asia and Russia, the genetic relatedness of its regional populations remains uncertain, likely owing to difficulties in specimen collection. Therefore, to appraise the phylogeographic patterns, genetic diversity, and morphological variety of U.major, the mitochondrial DNA of specimens collected from Japan, Korea and China were subjected to molecular phylogenetic analyses of COI genes, alongside morphological assessment. As a result, we discovered four principal groups; of these, Group 1 consisted predominantly of Japanese specimens, while Groups 3 and 4 were interpreted as having originated from the continent. Group 2 exhibited genetic segregation from both continental and Japanese descent. Group 1 mostly comprising Japanese specimens implies that the planktonic larvae of U.major were disseminated north and south by ocean currents encompassing the Japanese archipelago. In contrast, individuals probably originating from the continent were discovered in Lake Notoro, Hokkaido and Matsukawa-ura, Fukushima in northeastern Japan, indicating possible introduction from the continent through ocean currents or unintentional introduction with other organisms imported. Additionally, one of the specimens collected from Matsukawa-ura exhibited significant genetic and morphological differences from other specimens, suggesting the possibility of being a subspecies. The outcomes of this study not only offer valuable insights into the origins of distribution of U.major but also introduce a novel challenge of assessing the coexistence of two routes: natural and anthropogenic dispersion.

Phylogeography and chromosome number variation in Micranthes nelsoniana and related species (Saxifragaceae) in Northeast Asia

Abstract Micranthes nelsoniana possesses multiple different variants and numerous chromosomes. Based on the internal transcribed spacer (ITS) and chloroplast (cp)DNA sequences, the phylogeography of M. nelsoniana and its relatives in Northeast Asia was investigated, with extensive sampling around the Kuril Islands. The Arctic–Asian continent and a clade of marginal islands were the two main groupings that comprised the ITS phylogenetic tree. The island clade was separated into five well-supported clades: Kamchatka and Hokkaido highlands, Kuril–Aleutian Islands, southern Kuril Islands, Japanese archipelago, and Primorye region. Micranthes fusca was found in Japan and in the southern Kuril Islands. It is a separate species that created several types of hybrids between M. nelsoniana in the centre of the Kuril Islands based on a comparison of the ITS and cpDNA networks. Micranthes nelsoniana and M. ohwii appear to have hybridized in the northern Kuril Islands. Cytological investigation on the local species of M. nelsoniana showed that the chromosomal numbers are: 2n = 24, 26, 28, 30, 50, and 80. Among them, two usual numbers to this area, 2n = 24 and 50, appear to encourage interspecific gene exchange. The genomes of Hokkaido plants with high chromosome counts were cloned, revealing that they contained genes of both continental and marginal origins. This study revealed the crucial role of marginal islands along Northeast Asia in the genetic diversity of M. nelsoniana and related species.

Natural Selection Signatures in the Hondo and Ryukyu Japanese Subpopulations.

Natural selection signatures across Japanese subpopulations are under-explored. Here we conducted genome-wide selection scans with 622,926 single nucleotide polymorphisms for 20,366 Japanese individuals, who were recruited from the main-islands of Japanese Archipelago (Hondo) and the Ryukyu Archipelago (Ryukyu), representing two major Japanese subpopulations. The integrated haplotype score (iHS) analysis identified several signals in one or both subpopulations. We found a novel candidate locus at IKZF2, especially in Ryukyu. Significant signals were observed in the major histocompatibility complex region in both subpopulations. The lead variants differed and demonstrated substantial allele frequency differences between Hondo and Ryukyu. The lead variant in Hondo tags HLA-A*33:03-C*14:03-B*44:03-DRB1*13:02-DQB1*06:04-DPB1*04:01, a haplotype specific to Japanese and Korean. While in Ryukyu, the lead variant tags DRB1*15:01-DQB1*06:02, which had been recognized as a genetic risk factor for narcolepsy. In contrast, it is reported to confer protective effects against type 1 diabetes and human T lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis. The FastSMC analysis identified 8 loci potentially affected by selection within the past 20-150 generations, including 2 novel candidate loci. The analysis also showed differences in selection patterns of ALDH2 between Hondo and Ryukyu, a gene recognized to be specifically targeted by selection in East Asian. In summary, our study provided insights into the selection signatures within the Japanese and nominated potential sources of selection pressure.

The determinants of airline networks in the island regions of Japan

This study aims to show the determinants of the airline’s networks in Japanese island regions. Transportation systems are generally needed for residents in island regions to maintain their livelihood. Meanwhile, it is also necessary for people who live in outside regions such as tourists. Therefore, the transportation systems would be significant to maintain both tourism industries and the social situations in many of islands in Japan. This study, first, applied the network analysis to verify the nexus of connections among the transportation network in island regions in Japan. Degree centrality was calculated, and the result shows that some islands which is well-known as the tourism destinations located in southern part of Japan obtained many of connections to other places including other islands, as well as the mainland. Then regression model with the result of network analysis was composed and estimated by maximum likelihood method. The outcome shows that the situations of island society such as aged problem and economy in the islands would be influenced to maintain the airlines, as well as the amount of tourism demand. From these results, this paper concluded that both internal situations of island society and the tourism demand would be important to maintain island’s transportation system.

Development and characterization of expressed sequence tag-simple sequence repeat markers for Anaphalis margaritacea var. yedoensis (Asteraceae).

RNA-sequencing was used to develop 16 microsatellite markers for the pearly everlasting, Anaphalis margaritacea var. yedoensis (Franch. et Sav.) Ohwi (Asteraceae), which inhabits gravel bars throughout the Japanese archipelago. The mean number of alleles for these 16 markers in two populations in the Hokkaido and Shizuoka Prefectures, was 3.5 and 4.0, respectively, while the mean expected heterozygosity was 0.525 and 0.560, respectively, with a significant genetic differentiation between the two populations. All markers could also be amplified in two conspecific taxa, A. margaritacea var. margaritacea and var. angustifolia, whereas 11 of the 16 markers were amplifiable in two congeneric species, A. sinica and A. alpicola. These newly developed microsatellite markers will support understanding of population genetics and mating systems in A. margaritacea var. yedoensis, and several will potentially be of use in similar studies in other Anaphalis species.

Genetic differentiation and local adaptation of the Japanese honeybee, Apis cerana japonica.

We examine the population genetic structure and divergence among the regional populations of the Japanese honeybee, Apis cerana japonica, by re-sequencing the genomes of 105 individuals from the three main Japanese islands with diverse climates. The genetic structure results indicated that these individuals are distinct from the mainland Chinese A. cerana samples. Furthermore, population structure analyses have identified three genetically distinct geographic regions in Japan: Northern (Tohoku-Kanto-Chubu districts), Central (Chugoku district), and Southern (Kyushu district). In some districts, "possible non-native" individuals, likely introduced from other regions in recent years, were discovered. Then, genome-wide scans were conducted to detect candidate genes for adaptation by two different approaches. We performed a population branch statistics (PBS) analysis to identify candidate genes for population-specific divergence. A latent factor mixed model (LFMM) was used to identify genes associated with climatic variables along a geographic gradient. The PBSmax analysis identified 25 candidate genes for population-specific divergence whereas the LFMM analysis identified 73 candidate genes for adaptation to climatic variables along a geographic gradient. However, no common genes were identified by both methods.

Diet-related factors strongly shaped the gut microbiota of Japanese macaques.

Although knowledge of the functions of the gut microbiome has increased greatly over the past few decades, our understanding of the mechanisms governing its ecology and evolution remains obscure. While host genetic distance is a strong predictor of the gut microbiome in large-scale studies and captive settings, its influence has not always been evident at finer taxonomic scales, especially when considering among the recently diverged animals in natural settings. Comparing the gut microbiome of 19 populations of Japanese macaques Macaca fuscata across the Japanese archipelago, we assessed the relative roles of host genetic distance, geographic distance and dietary factors in influencing the macaque gut microbiome. Our results suggested that the macaques may maintain a core gut microbiome, while each population may have acquired some microbes from its specific habitat/diet. Diet-related factors such as season, forest, and reliance on anthropogenic foods played a stronger role in shaping the macaque gut microbiome. Among closely related mammalian hosts, host genetics may have limited effects on the gut microbiome since the hosts generally have smaller physiological differences. This study contributes to our understanding of the relative roles of host phylogeography and dietary factors in shaping the gut microbiome of closely related mammalian hosts.

New Perspectives on the Behavioral Patterns of Early Modern Humans from the Japanese Islands

This paper presents archaeological research of the Early Upper Paleolithic in the Japanese Islands, introducing the findings of recent research there into early modern humans. The authors provide background to the natural environment of the Upper Paleolithic while offering an overview of research in the area. Five important research topics, related to behavioral modernity of early modern humans, will be described. Based on them, new information and perspectives about the behavioral patterns of early modern humans are discussed with a focus on the Mt. Ashitaka area.