Japanese Islands Research Articles

Population pressure and prehistoric violence in the Yayoi period of Japan

The causes of prehistoric inter-group violence have been a subject of long-standing debate in archaeology, anthropology, and other disciplines. Although population pressure has been considered as a major factor, due to the lack of available prehistoric data, few studies have directly examined its effect so far. In the present study, we used data on skeletal remains from the middle Yayoi period of the Japanese archipelago, where archaeologists argued that an increase of inter-group violence in this period could be explained by a population-pressure hypothesis. We quantitatively examine the effect of population pressure on the frequency of inter-group violence by compiling an exhaustive data set. We collected demographic information based on burial jars (kamekan) and the frequency of violence based on the ratio of injured individuals. The results are consistent with the hypothesis, i.e., high population density can promote inter-group violence.

Bronze Age Globalisation and Eurasian Impacts on Later J\u014dmon Social Change

From northern China, millet agriculture spread to Korea and the Maritime Russian Far East by 3500–2700 BC. While the expansion of agricultural societies across the Sea of Japan did not occur until around 900 BC, the intervening period saw major transformations in the Japanese archipelago. The cultural florescence of Middle Jōmon central Honshu underwent a collapse and reorganisation into more decentralised settlements. Mobility increased as Late Jōmon influences spread from eastern into western Japan, and populations expanded to offshore islands such as Okinawa and the Kurils. In Kyushu and other parts of western Japan, the eastern Jōmon expansion was associated with the cultivation of adzuki and soybeans but, contrary to earlier assessments, there is no evidence for the introduction of cereal crops at this time. Here, we analyse archaeological and historical linguistic evidence of connections between the Eurasian mainland and the Japanese Islands c. 3500 to 900 BC. A re-evaluation of archaeological material discussed since the 1920s concludes that the transformations in Jōmon society during this period were at least in part a response to contacts with Eurasian Bronze Age cultures. Evidence for linguistic contact between Koreanic and the Ainuic languages which are presumed to have been spoken by Jōmon populations is also consistent with new Bronze Age mobilities. Although prehistoric Japan was one of the most isolated regions of Eurasia, we conclude that the historical evolution of societies in the Japanese archipelago after the third millennium BC was linked with processes of Bronze Age globalisation.

Topographic Amplification of Crustal Subsidence by the Rainwater Load of the 2019 Typhoon Hagibis in Japan

AbstractThe super typhoon Hagibis traveled northeastward through eastern Honshu, Japan, causing disastrous heavy rainfalls along its path on October 11 and 12, 2019. We performed a comprehensive space geodetic study of water brought by this typhoon using a dense network of Global Navigation Satellite System (GNSS) receivers in Japan. First, we studied the time evolution of altitude‐corrected precipitable water vapor field and compare the movement of water vapor centroid with the rain distribution from radar rain gauge analyzed precipitation. The total amount of water vapor derived by spatially integrating precipitable water vapor on land remained steady at ∼20 Gt. The total precipitation by this typhoon was ∼92, and ∼33 Gt of it fell onto the land area of eastern Honshu. Next, we studied crustal subsidence caused by the typhoon rainwater as surface load. The GNSS stations located under the typhoon path temporarily subsided 1–2 cm on the landfall day and the subsidence mostly recovered on the next day. Using the vertical crustal movement data, we estimated the distribution of surface water in eastern Honshu assuming the layered spherical earth. The amount of the surface load on October 12 was ∼71 Gt, which significantly exceeds the cumulative rainfall on land. We consider that the excess subsidence largely originates from the selective deployment of GNSS stations in the concave topography, for example, along valleys and within basins, in the mountainous Japanese Islands.

Phylogenomics and biogeography of Wisteria: Implications on plastome evolution among inverted repeat‐lacking clade (IRLC) legumes

AbstractThe genus Wisteria (Fabaceae) is disjunctly distributed in eastern Asian and eastern North American temperate deciduous forests, and it is widely cultivated around the world as spectacular garden plants. It is a member of inverted repeat‐lacking clade (IRLC). The IRLC Species are characterized by the loss of an IR region in their plastomes, which has long been of great interest. In this research, we report whole plastome sequences from all four Wisteria species and a Wisteriopsis japonica, combining these with existing data to explore phylogenetic relationships and biogeography of Wisteria, as well as plastome evolution of IRLC species. Phylogenetic analyses recognized a clade containing Glycyrrhiza–Wisteriopsis–Wisteria as sister to the remaining genera of IRLC. North American Wisteria frutescens and the three Asian species formed reciprocal clades, and Wisteria brachybotrys was sister to Wisteria floribunda and Wisteria sinensis. Wisteria may have originated in Japan near the boundary of the Oligocene and Miocene. The disappearance of Bering Land Bridge in the late Miocene might lead to the Eastern Asian–Eastern North American disjunction of Wisteria. Allopatric speciation of Wisteria between the Japanese archipelago and the Asian continent in the Quaternary increased the species richness of eastern Asia in comparison with eastern North America. Synonymous substitution rates (dS) of protein‐coding genes in the IRLC species were around 2‐fold (SC genes) or 11‐fold (IR genes) higher than those of non‐IRLC species. For both SC and IR genes, herbaceous legumes have around 3‐fold higher dS than woody ones. Both loss of one IR region and herbaceous habit elevated substitution rates of the plastomes.

Geological and paleoclimatic events reflected in phylogeographic patterns of intertidal arthropods (Acari, Oribatida, Selenoribatidae) from southern Japanese islands

Geological and paleoclimatic events reflected in phylogeographic patterns of intertidal arthropods (Acari, Oribatida, Selenoribatidae) from southern Japanese islands

An analysis of the demographic history of the risk allele R4810K in RNF213 of moyamoya disease.

BackgroundRing finger protein 213 (RNF213) is a susceptibility gene of moyamoya disease (MMD). A previous case–control study and a family analysis demonstrated a strong association of the East Asian‐specific variant, R4810K (rs112735431), with MMD. Our aim is to uncover evolutionary history of R4810K in East Asian populations.MethodsThe RNF213 locus of 24 MMD patients in Japan were sequenced using targeted‐capture sequencing. Based on the sequence data, we conducted population genetic analysis and estimated the age of R4810K using coalescent simulation.ResultsThe diversity of the RNF213 gene was higher in Africans than non‐Africans, which can be explained by bottleneck effect of the out‐of‐Africa migration. Coalescent simulation showed that the risk variant was born in East Asia 14,500–5100 years ago and came to the Japanese archipelago afterward, probably in the period when the known migration based on archaeological evidences occurred.ConclusionsAlthough clinical data show that the symptoms varies, all sequences harboring the risk allele are almost identical with a small number of exceptions, suggesting the MMD phenotypes are unaffected by the variants of this gene and rather would be more affected by environmental factors.

How co-distribution of two related azaleas (Rhododendron) developed in the Japanese archipelago: insights from evolutionary and demographic analyses

Plants growing in similar climates with extensively overlapping distributions may exhibit similar phylogeographic patterns, due to similarities in range shifts during past climatic oscillations. We tested and exploited this expectation in a comparison of the evolutionary and demographic histories of two related and co-distributed species endemic to Japan—Rhododendron pentaphyllum and R. quinquefolium. Genetic variation in sequences of noncoding chloroplast DNA regions and hundreds of nuclear single nucleotide polymorphisms were used to investigate 191 individuals from 13 populations of R. pentaphyllum and 142 individuals from 10 populations of R. quinquefolium. We found that the two species were not each other’s closest relative, and we found different times to the most recent common ancestor of extant populations based on both chloroplast DNA and nuclear SNPs. Rhododendron pentaphyllum exhibited higher genetic variation between populations than R. quinquefolium, while the two species had similar patterns of genetic divergence between regions with slightly different divergence times. These lines of evidence suggest that the similar ranges of the two species are the result of repeated range shifts since speciation during climatic oscillations.

Migration-tracking integrated phylogeography supports long-distance dispersal-driven divergence for a migratory bird species in the Japanese archipelago.

Long‐distance dispersal (LDD) outside a species' breeding range contributes to genetic divergence. Previous phylogeographic studies of migratory bird species have not discriminated LDD from vicariant speciation in their diversification process. We conducted an integrative phylogeographic approach to test the LDD hypothesis, which predicts that a Japanese migratory bird subspecies diverged from a population in the coastal region of the East China Sea (CRECS) via LDD over the East China Sea (ECS). Haplotype networks of both mitochondrial and nuclear genes of its three subspecies were reconstructed to examine whether the Japanese subspecies of the Brown Shrike (Lanius cristatus superciliosus) diverged from an ancestral CRECS population. A species distribution model (SDM) for the Japanese subspecies was constructed using bioclimatic variables under the maximum entropy algorithm. It was projected backwards to the climate of the last glacial maximum (LGM) to infer the candidate source area of colonization. A migratory route of L. c. superciliosus, which possibly reflects a candidate past colonization route, was tracked by light‐level geolocators. Molecular phylogenetic networks suggest that the Japanese subspecies diverged from a population in the CRECS and maintained anciently diverged haplotypes. The SDM inferred that the emerged continental shelf of the ECS and the present CRECS were suitable breeding areas for the Japanese subspecies during the LGM. A major migratory route for L. c. superciliosus was inferred between the CRECS and the Japanese archipelago across the ECS. Our integrative approach supported the LDD hypothesis for divergence of the Japanese subspecies of the Brown Shrike. Shrinkage of the ECS may have been responsible for successful population establishment, due to a sufficient number of migrants overshooting to the Japanese archipelago from the CRECS. Our framework provides a new phylogeographic scenario for this region. Discriminating LDD and vicariance models helps improve our understanding of the phylogeographic histories of migratory species.

Numerical simulations of upslope fog observed at Beppu Bay in Oita Prefecture, Japan

AbstractThe present study focussed on the formation of upslope fog. This fog causes chronic expressway closures near Beppu Bay (BB) in Oita Prefecture, Japan. A dense fog event, occurring on 3 and 4 May 2020, resulting from the passage of an extratropical cyclone through the southern Japanese islands, was simulated using the Weather Research and Forecasting (WRF) numerical model. The simulation results indicated that warm and humid air with a lifting condensation level less than 20 m flowed into a plain from BB. Simulated fog and poor visibility were more severe on mountain slope adjacent to BB than on the surroundings. Here, the westward horizontal flux of water vapour by the wind flow was prolonged at lower heights. Analyses of the simulated elements verified that the upslope fog was induced by moist adiabatic cooling of the air lifted by the upslope winds. At the mature stage of upslope fog, a simulated local vertical circulation generated in conjunction with the upper synoptic flow extended the dense fog into the upper atmosphere over BB. During the decaying stage of upslope fog on mountain, a fog covered on the entire BB. This was associated with weakening winds at lower heights. Sensitivity experiments for model boundary conditions supported the importance of mountain steepness and the rectangular shape of BB for the generation of upslope fog. Finally, an application possibility of dense fog forecasts was discussed by using a simulated difference in the equivalent potential temperature between the base of the mountain and Beppuwan expressway interchange located midslope.

Characteristics and Controlling Factors of the Drought Runoff Coefficient

Increasing water demand due to population growth, economic development, and changes in rainfall patterns due to climate change are likely to alter the duration and magnitude of droughts. Understanding the relationship between low-flow conditions and controlling factors relative to the magnitude of a drought is important for establishing sustainable water resource management based on changes in future drought risk. This study demonstrates the relationship between low-flow and controlling factors under different severities of drought. I calculated the drought runoff coefficient for six types of occurrence probability, using past observation data of annual total discharge and precipitation in the Japanese archipelago, where multiple climate zones exist. Furthermore, I investigated the pattern of change in the drought runoff coefficient in accordance with the probability of occurrence of drought, and relationships among the coefficient and geological, land use, and topographical factors. The drought runoff coefficient for multiple drought magnitudes exhibited three behaviors, corresponding to the pattern of precipitation. Results from a generalized linear model (GLM) revealed that the controlling factors differed depending on the magnitude of the drought. During high-frequency droughts, the drought runoff coefficient was influenced by geological and vegetation factors, whereas land use and topographical factors influenced the drought runoff coefficient during low-frequency droughts. These differences were caused by differences in runoff, which dominated stream discharge, depending on the magnitude of the drought. Therefore, for effective water resource management, estimation of the volume of drought runoff needs to consider the pattern of precipitation, geology, land use, and topography.

De novo Genome Assembly of the Raccoon Dog (Nyctereutes procyonoides).

The raccoon dog, Nyctereutes procyonoides (NCBI Taxonomy ID: 34880, Figure 1a) belongs to the family Canidae, with foxes (genus Vulpes) being their closest relatives (Lindblad-Toh et al., 2005; Sun et al., 2019). Its original distribution in East Asia ranges from south-eastern Siberia to northern Vietnam and the Japanese islands. In the early 20th century, the raccoon dog was introduced into Western Russia for fur breeding and hunting purposes, which led to its widespread establishment in many European countries, Figure 1b. Together with the raccoon (Procyon lotor), it is now listed in Europe as an invasive species of Union concern (Regulation (EU) No. 1143/2014) and member states are required to control pathways of introductions and manage established populations. Open in a separate window Figure 1 (a) Picture of an adult specimen of raccoon dog (Nyctereutes procyonoides), copyright © Dorian D. Dorge. (b) Native (orange) and introduced (purple) distributions ranges of raccoon dog (source IUCN red list). (c) Workflow of genome assembly and annotation followed in this study. (d) Blob plot showing read depth of coverage, GC content and size of each scaffold. Size of the blobs correspond to size of the scaffold and color corresponds to taxonomic assignment of BLAST (blue = Carnivora). (e) Whole genome synteny, obtained with Jupiterplot, between the Canis lupus familiaris chromosome-level assembly (on the left) and the raccoon dog genome assembly obtained in this study (on the right). The lines indicate aligned regions between the two assemblies.

Breeding evidence of the vulnerable Swinhoe's Rail (Coturnicops exquisitus) in Japan

The Swinhoe's Rail (Coturnicops exquisitus) is the world's smallest, and among the most poorly studied, Rallidae species. While the Japanese archipelago has long been considered a wintering area of this species, vocalizing Swinhoe's Rails have recently been observed during its breeding season in multiple distinct wetlands in northern Japan. During the summer of 2018, we investigated the breeding status of this species at a wetland in the Yufutsu Plain in central Hokkaido, where vocalizing Swinhoe's Rails have been recorded since 2012. To achieve our observations, we combined camera trapping and line-transect surveys with playbacks. Our surveys confirmed the presence of at least 1 family of Swinhoe's Rail and its abandoned nest. We also obtained a previous observation record of a family of this species from local birdwatchers at the Hotokenuma wetland in Aomori Prefecture. This study provides the first breeding evidence of Swinhoe's Rail in Japan, and suggests that this secretive, endangered rail species is a breeding summer visitor to northern Japan.

Post-seismic crustal internal deformation in a layered earth model

SUMMARY This study introduces a novel method for computing post-seismic crustal internal deformation in a layered earth model. The surface dislocation Love number (DLN) calculated by the reciprocity theorem was implemented as the initial value. Furthermore, numerical integration of the value from the Earth's surface to the interior was undertaken to obtain the internal DLN. This method does not require a combination of the general solution and particular solution for the calculation of internal deformation above the seismic source, thus avoiding the loss of precision. When the post-seismic deformation within a certain period is calculated, the particular solutions at the beginning and end of the considered period cancel each other. This simplifies the calculation of post-seismic internal deformation. The numerical results depict that as the degrees increase, the post-seismic DLN reaches stability in a shorter interval of time. Thus, for improved efficiency of the post-seismic internal deformation calculation, the post-seismic DLNs should be calculated within 2000 degree and integrated with the coseismic results. As an application, the post-seismic Coulomb failure stress changes (∆CFS) induced by the 2011 Tohoku-Oki earthquake in the near field around the Japanese archipelagos and two major faults in Northeast China were simulated. The results exhibit that the ∆CFS values in the near field agree well with those simulated by the method in a half-space layered earth model, thus verifying the present method. The coseismic ∆CFS on the Mishan-Dunhua fault in Northeast China, as an example, is only 0.094–0.668 KPa. However, the ∆CFS caused by the viscoelastic relaxation of the mantle within 5 yr following the 2011 Tohoku-Oki event on the same fault exceeds the coseismic results. Therefore, the cumulative effect of the viscoelastic relaxation of the mantle is deserving of attention.

Tourism netnography: how travel bloggers influence destination image

ABSTRACT Travel bloggers are among digital influencers who share travels with their followers and impact their opinions. This study applies netnography to gain a better understanding of this influence on destination image formation. By choosing Okinawa as the destination, the online communications between two travel bloggers and their respective followers were studied. As most of their followers had no prior image towards Okinawa, the researchers could study how the promoted destination image was perceived by the followers. The findings revealed their practices as grabbing followers’ attention, self-discovery, followers’ involvement and sharing information. Followers were surprised and excited by this discovery and even some of them expressed intention to visit this Japanese archipelago. This study provides a protocol of using netnography for identifying destination image attributes through social media communications along with theoretical and managerial implications in tourism promotion and digital marketing.

Phylogenetic origin of two Japanese Torreya taxa found in two regions with strongly contrasting snow depth.

The Japanese archipelago exhibits a notable difference in snow depth in winter, deep snow on the Sea of Japan side and low snow cover on the Pacific Ocean side. This contrasting pattern has shaped the distribution of infraspecific taxon pairs in a range of woody plants, with taxa found on the Sea of Japan side typically exhibiting a stunted shrub form with multiple decumbent stems. The phylogenetic origin of these taxon pairs is unknown, i.e., whether the two taxa diverged from the same species or if they have different origins. This study aimed to reveal the phylogenetic origin of two varieties of Torreya nucifera (Taxaceae); var. nucifera is a tree found on the Pacific Ocean side, whereas var. radicans is a shrub found on the Sea of Japan side. We examined the phylogenetic relationships of the two varieties and worldwide Torreya taxa using whole chloroplast genomes, chloroplast DNA fragments, and the nuclear ribosomal internal transcribed spacer (ITS). The whole chloroplast genome phylogeny indicated that T. nucifera var. radicans was a sister taxon to Chinese T. grandis, rather than to var. nucifera. In contrast, the nuclear ITS phylogeny indicated that while several haplotypes of T. nucifera var. radicans were closely related to T. grandis, most haplotypes of T. nucifera var. radicans formed a single clade with those of var. nucifera. This implies that the homogenization of the ITS has occurred between the two taxa, while taxon-specific chloroplast DNA haplotypes were retained. These discordant phylogenies suggested that the two taxa have different phylogenetic origins, but have an intricate evolutionary history, involving inter-taxa hybridization and gene flow, possibly when their distributions were confined to sympatric refugia. Given the genetic evidence and distinct difference in growth form, we propose that T. nucifera var. radicans should be taxonomically treated as a distinct species, T. fruticosa.

Low-Frequency Seismic Noise Properties in the Japanese Islands.

The records of seismic noise in Japan for the period of 1997–2020, which includes the Tohoku seismic catastrophe on 11 March 2011, are considered. The following properties of noise are analyzed: The wavelet-based Donoho–Johnston index, the singularity spectrum support width, and the entropy of the wavelet coefficients. The question of whether precursors of strong earthquakes can be formulated on their basis is investigated. Attention is paid to the time interval after the Tohoku mega-earthquake to the trends in the mean properties of low-frequency seismic noise, which reflect the constant simplification of the statistical structure of seismic vibrations. Estimates of two-dimensional probability densities of extreme values are presented, which highlight the places in which extreme values of seismic noise properties are most often realized. The estimates of the probability densities of extreme values coincide with each other and have a maximum in the region: , . The main conclusions of the conducted studies are that the preparation of a strong earthquake is accompanied by a simplification of the structure of seismic noise. It is shown that bursts of coherence between the time series of the day length and the noise properties within annual time window precede bursts of released seismic energy. The value of the lag in the release of seismic energy relative to bursts of coherence is about 1.5 years, which can be used to declare a time interval of high seismic hazard after reaching the peak of coherence.

Antiquity and tectonic lineage of Japanese Islands: New discovery of Archean–Paleoproterozoic Complex

A new rock complex has been discovered from the Tsuwano area of Southwest Japan. This granitic rock complex namely, Tsuwano Complex contains foliated granitic gneiss, massive granitoids, and metaquartzite, forming a distinct unit at the westernmost end of the east-west elongate Maizuru Terrane. The above-mentioned litho-assemblage is characteristically different in appearance from the typical rocks of the Maizuru Terrane as well as the surrounding Jurassic and Permian accretionary rocks. We report here the zircon U-Pb LA-ICP-MS geochronological data of the rocks of this Tsuwano Complex. The comprehensive geochronological data indicate that this complex is much older than the surrounding rocks of the Maizuru Terrane. Zircon cores of the granitic gneiss yield possible magmatic age at ca. 2700 and 2500 Ma, while rim parts show a possible metamorphic age of ca. 1850 Ma. Associated dioritic to tonalitic granitoids also show a comparable age of crystallization at ca. 1850 Ma, indicating Neoarchean granitic rocks suffering a thermal overprinting and associated granitoid magmatism at Paleoproterozoic era. The exposed metaquartzite also yielded Neoarchean detrital zircon grains with the calculated maximum age of deposition at ca. 2430 Ma. While, all the other studied rocks including the grayish granitoids, felsic tuff, and metagabbro yield Paleozoic to Mesozoic ages. This is the first discovery of a Precambrian basement rock complex from the Japanese main islands. Based on the present geochronological dataset, we propose for a correlation and paleo-positioning of these basement rocks on the East Asian cratonic margin and a possible tectonic model of its evolution.

Development and characterization of nuclear microsatellite markers to reveal the neutral demographic background of flower color polymorphism in Geranium thunbergii (Geraniaceae).

Nuclear microsatellite markers were developed for Geranium thunbergii, an herbaceous plant characterized by petal color polymorphism. Utilizing RNA sequencing data obtained by next-generation sequencing techniques, we developed and characterized 19 polymorphic microsatellite markers with two to 12 alleles in the nuclear genome. These markers will be used to reveal the genetic structure and demographic history of G. thunbergii in the Japanese archipelago, which will elucidate the genetic background of flower color polymorphism among populations.

Prevalence of Shallow Low‐Frequency Earthquakes in the Continental Crust

AbstractLow‐frequency earthquakes (LFEs) that predominantly occur at depths of 20–30 km are categorized as a particular class of earthquakes whose spectral power is concentrated at 1–4 Hz. While the tectonic LFEs along megathrust boundaries occur as shear failure, the genesis of LFEs in the continental plate is poorly understood due to the diversity of focal mechanism solutions. Here we conduct a systematic survey of LFEs using two metrics (frequency index and peak frequency) that characterize the frequency content of the waveforms, and show that LFEs are prevalent in the upper crust beneath the Japanese Islands, even in non‐volcanic regions. Shallow LFEs are most common near tectonic boundaries and are temporarily activated in the aftershock sequences of large (M ≥ 6.5) crustal earthquakes. The widespread distribution of shallow LFEs suggests that a lower crustal rheology is not necessary for their genesis. We infer that failure along frictionally weakened faults due to high pore‐fluid pressures is a primary control for the enrichment of low‐frequency energy. The observed differences in the frequency content are probably due to differences in the pore‐fluid pressure along each fault, which influences the rupture velocity and magnitude of the tensile component during shear failure. Our observations may lead to a more unified model of earthquake generation, thereby providing a better understanding of how earthquakes release the stress accumulated in the Earth.

Phylogeography of the northernmost distributed Anisocentropus caddisflies and their comparative genetic structures based on habitat preferences.

Knowledge of the factors that determine the distribution ranges of organisms is necessary to understand their evolutionary and ecological significance and contribution to biodiversity. A very effective mean of studying such factors is to compare the distribution characteristics and genetic structures of closely related species with differing habitat preferences. Freshwater aquatic insects are relatively easy to observe and the basis of their corresponding niche differentiation easier to identify. Freshwater habitats are categorized lotic or lentic water according to flow regime. In Japanese Islands, the genus Anisocentropus of the calamoceratid caddisfly, the target group in this study, was morphologically reconfirmed that three species, that is, Anisocentropus kawamurai, A. pallidus, and A. magnificus. Among these, A. kawamurai prefers lotic environments and A. pallidus is adapted to lentic water habitats. The distribution range of these sister species overlaps within the Japanese Islands. We estimated the phylogeny and the evolutionary history of Anisocentropus caddisflies worldwide. We estimated divergence periods by two methods, a single locus with various specimens and multiple loci with reduced numbers of the specimens. As a result, we elucidated the phylogenetic position of Japanese species within the cosmopolitan genus Anisocentropus, and also revealed their dual origin. In addition, we demonstrated that the contrasting genetic structures between the sister species distributed in widely overlapping areas were due to differentiation in their respective adapted environmental preferences. Although, in general, it is known that species adapted to lentic water have greater dispersal potential and so are associated with wider distribution areas by means of examining their comparative genetic structures, we revealed a new pattern of genetic locality existing in the genetic structures of the species adapted to lentic water. We then present evidence that suggests the ecological preferences of a species are an important factor in understanding the evolutionary history of that species.