The origin of Mosuo people as revealed by mtDNA and Y chromosome variation

The Mosuo, living in the Lugu Lake area in northwest Yunnan Province, China, is the only matriarchal population in China. The Mosuo was officially identified as Naxi nationality although its relationship with Naxi remains controversial. We studied the genetic relationship between the Mosuo and five other ethnic groups currently residing in northwest Yunnan, i.e. Naxi, Tibetan, Bai, Yi and Pumi, by typing the genetic variations in mtDNA HVS1 and 21 Y chromosome markers (13 SNPs & 8 STR markers). We showed that the maternal lineages of the Mosuo bear the strongest resemblance with those found in Naxi while its paternal lineages are more similar to those that are prevalent in Yunnan Tibetan. The marked difference between paternal and maternal lineages may be attributable to the genetic history, matriarchal structure, and visiting marriage.     

The origin of Mosuo people as revealed by mtDNA and Y chromosome variation

The Mosuo, living in the Lugu Lake area in northwest Yunnan Province, China, is the only matriarchal population in China. The Mosuo was officially identified as Naxi nationality although its relationship with Naxi remains controversial. We studied the genetic relationship between the Mosuo and five other ethnic groups currently residing in northwest Yunnan, i.e. Naxi, Tibetan, Bai, Yi and Pumi, by typing the genetic variations in mtDNA HVS1 and 21 Y chromosome markers (13 SNPs & 8 STR markers). We showed that the maternal lineages of the Mosuo bear the strongest resemblance with those found in Naxi while its paternal lineages are more similar to those that are prevalent in Yunnan Tibetan. The marked difference between paternal and maternal lineages may be attributable to the genetic history, matriarchal structure, and visiting marriage.     

Regional differences in the distribution of the sub-Saharan, West Eurasian, and South Asian mtDNA lineages in Yemen

Despite its key location for population movements out of and back into Africa, Yemen has not yet been sampled on a regional level for an investigation of sub-Saharan, West Eurasian, and South Asian genetic contributions. In this study, we present mitochondrial DNA (mtDNA) data for regionally distinct Yemeni populations that reveal different distributions of mtDNA lineages. An extensive database of mtDNA sequences from North and East African, Middle Eastern and Indian populations was analyzed to provide a context for the regional Yemeni mtDNA datasets. The groups of western Yemen appear to be most closely related to Middle Eastern and North African populations, while the eastern Yemeni population from Hadramawt is most closely related to East Africa. Furthermore, haplotype matches with Africa are almost exclusively confined to West Eurasian R0a haplogroup in southwestern Yemen, although more sub-Saharan L-type matches appear in more northern Yemeni populations. In fact, Yemeni populations have the highest frequency of R0a haplotypes detected to date, thus Yemen or southern Arabia may be the site of the initial expansion of this haplogroup. Whereas two variants of the sub-Saharan haplogroup M1 were detected only in southwestern Yemen close to the Bab el-Mandeb Strait, different non-African M haplotypes were detected at low frequencies (approximately 2%) in western parts of the country and at a higher frequency (7.5%) in the Hadramawt. We conclude that the Yemeni gene pool is highly stratified both regionally and temporally and that it has received West Eurasian, Northeast African, and South Asian gene flow.     

Origins and genetic diversity of New World Creole cattle: inferences from mitochondrial and Y chromosome polymorphisms

The ancestry of New World cattle was investigated through the analysis of mitochondrial and Y chromosome variation in Creoles from Argentina, Brazil, Mexico, Paraguay and the United States of America. Breeds that influenced the Creoles, such as Iberian native, British and Zebu, were also studied. Creoles showed high mtDNA diversity (H = 0.984 ± 0.003) with a total of 78 haplotypes, and the European T3 matriline was the most common (72.1%). The African T1a haplogroup was detected (14.6%), as well as the ancestral African‐derived AA matriline (11.9%), which was absent in the Iberian breeds. Genetic proximity among Creoles, Iberian and Atlantic Islands breeds was inferred through their sharing of mtDNA haplotypes. Y‐haplotype diversity in Creoles was high (H = 0.779 ± 0.019), with several Y1, Y2 and Y3 haplotypes represented. Iberian patrilines in Creoles were more difficult to infer and were reflected by the presence of H3Y1 and H6Y2. Y‐haplotypes confirmed crossbreeding with British cattle, mainly of Hereford with Pampa Chaqueño and Texas Longhorn. Male‐mediated Bos indicus introgression into Creoles was found in all populations, except Argentino1 (herd book registered) and Pampa Chaqueño. The detection of the distinct H22Y3 patriline with the INRA189‐90 allele in Caracú suggests introduction of bulls directly from West Africa. Further studies of Spanish and African breeds are necessary to elucidate the origins of Creole cattle, and determine the exact source of their African lineages.     

Multiple surveys employing a new sample‐processing protocol reveal the genetic diversity of placozoans in Japan

Placozoans, flat free‐living marine invertebrates, possess an extremely simple bauplan lacking neurons and muscle cells and represent one of the earliest‐branching metazoan phyla. They are widely distributed from temperate to tropical oceans. Based on mitochondrial 16S rRNA sequences, 19 haplotypes forming seven distinct clades have been reported in placozoans to date. In Japan, placozoans have been found at nine locations, but 16S genotyping has been performed at only two of these locations. Here, we propose a new processing protocol, “ethanol‐treated substrate sampling,” for collecting placozoans from natural environments. We also report the collection of placozoans from three new locations, the islands of Shikine‐jima, Chichi‐jima, and Haha‐jima, and we present the distribution of the 16S haplotypes of placozoans in Japan. Multiple surveys conducted at multiple locations yielded five haplotypes that were not reported previously, revealing high genetic diversity in Japan, especially at Shimoda and Shikine‐jima Island. The observed geographic distribution patterns were different among haplotypes; some were widely distributed, while others were sampled only from a single location. However, samplings conducted on different dates at the same sites yielded different haplotypes, suggesting that placozoans of a given haplotype do not inhabit the same site constantly throughout the year. Continued sampling efforts conducted during all seasons at multiple locations worldwide and the development of molecular markers within the haplotypes are needed to reveal the geographic distribution pattern and dispersal history of placozoans in greater detail.     

Foundations for conservation of intraspecific genetic diversity revealed by analysis of phylogeographical structure in the endangered endemic lizard Podarcis lilfordi

Aim  To describe and analyse phylogeographical patterns in the endangered endemic lizard Podarcis lilfordi from across its remaining range and thereby establish baseline information on genetic diversity that will help determine conservation priorities and assist future reintroduction programs.
Location  Balearic Islands, Spain.
Methods  We analysed mitochondrial DNA (2382 bp sequence from eight genes) from 118 individuals and characterized the relationships among haplotypes using parsimony networks, as well as phylogenetic inference. Analyses of historical gene flow and population growth were used to provide further insights into population histories.
Results  Four unconnected parsimony networks were obtained that mirrored the main clades in the phylogenetic tree: (I) all Menorcan populations, (II) Dragonera, Malgrats and Toro islands (Western Mallorca) (III and IV) and the remaining populations from Cabrera and Mallorca. Two major haplotype groups were detected in Menorca (I) and these provided signatures of a demographic expansion and asymmetrical historical gene flow, respectively, concordant with the expected direction of colonization from south to north of the island. Populations from western Mallorca (II) showed evidence of historical allopatric fragmentation events following isolation around the start of the Pleistocene. In networks III and IV, Cabreran populations appear to have become isolated from north and south Mallorca quite recently, with asymmetric gene flow indicating a northwards dispersal direction.
Main conclusions  P. lilfordi is a genetically diverse species that shows substantial mtDNA structuring both between regions and, at a finer scale, between some islet populations within regions. The precarious state of some islet populations shown here to be quite divergent (e.g. Toro island in western Mallorca) means that conservation of this intraspecific biodiversity requires urgent action.     

The maintenance of mitochondrial genetic variation by negative frequency‐dependent selection

Mitochondrial genes generally show high levels of standing genetic variation, which is puzzling given the accumulating evidence for phenotypic effects of mitochondrial genetic variation. Negative frequency‐dependent selection, where the relative fitness of a genotype is inversely related to its frequency in a population, provides a potent and potentially general process that can maintain mitochondrial polymorphism. We assessed the change in mitochondrial haplotype frequencies over 10 generations of experimental evolution in 180 seed beetle populations in the laboratory, where haplotypes competed for propagation to subsequent generations. We found that haplotypes consistently increased in frequency when they were initially rare and decreased in frequency when initially common. Our results have important implications for the use of mtDNA haplotype frequency data to infer population level processes and they revive the general hypothesis that negative frequency‐dependent selection, presumably caused by habitat heterogeneity, may commonly promote polymorphism in ecologically relevant life history genes.     

Aeromonas hydrophila clinical and environmental ecotypes as revealed by genetic diversity and virulence genes

Aeromonas hydrophila strains recovered from clinical samples and ambient sources were phenotypically and genetically identified. In addition, the distribution of putative virulence factors was assayed. To determine the genetic diversity of these strains, random amplification of polymorphic DNA (RAPD) and enterobacterial repetitive intergenic consensus (ERIC)-PCR markers were used. The discriminatory ability of the techniques, using Simpson's index, was 0.96 for both methods. The most consistent dendrogram was obtained when RAPD and ERIC data were combined. The genetic diversity revealed a high intra-specific genetic diversity (h=0.364+/-0.024 and I=0.538+/-0.030). The strains showed a tendency to cluster according to their origin of isolation (best-cut test 0.80 and bootstrap values >50%). The present study demonstrates and quantifies the high intra-specific diversity within this species and reveals a clear differentiation of strains according to their ecological origin. The distribution of virulence-related genes confirm that A. hydrophila is a genetically heterogeneous species that harbour ecotypes which have different pathogenic potential to human and other animals.     

Phylogeography, genetic structure and diversity in the endangered bearded vulture (Gypaetus barbatus, L) as revealed by mitochondrial DNA

Bearded vulture populations in the Western Palearctic have experienced a severe decline during the last two centuries that has led to the near extinction of the species in Europe. In this study we analyse the sequence variation at the mitochondrial control region throughout the species range to infer its recent evolutionary history and to evaluate the current genetic status of the species. This study became possible through the extensive use of museum specimens to study populations now extinct. Phylogenetic analysis revealed the existence of two divergent mitochondrial lineages, lineage A occurring mainly in Western European populations and lineage B in African, Eastern European and Central Asian populations. The relative frequencies of haplotypes belonging to each lineage in the different populations show a steep East-West clinal distribution with maximal mixture of the two lineages in the Alps and Greece populations. A genealogical signature for population growth was found for lineage B, but not for lineage A; futhermore the Clade B haplotypes in western populations and clade A haplo-types in eastern populations are recently derived, as revealed by their peripheral location in median-joining haplotype networks. This phylogeographical pattern suggests allopatric differentiation of the two lineages in separate Mediterranean and African or Asian glacial refugia, followed by range expansion from the latter leading to two secondary contact suture zones in Central Europe and North Africa. High levels of among-population differentiation were observed, although these were not correlated with geographical distance. Due to the marked genetic structure, extinction of Central European populations in the last century re-sulted in the loss of a major portion of the genetic diversity of the species. We also found direct evidence for the effect of drift altering the genetic composition of the remnant Pyrenean population after the demographic bottleneck of the last century. Our results argue for the management of the species as a single population, given the apparent ecological exchangeability of extant stocks, and support the ongoing reintroduction of mixed ancestry birds in the Alps and planned reintroductions in Southern Spain.     

Population structure of Purple Sandpipers (Calidris maritima) as revealed by mitochondrial DNA and microsatellites

The Purple Sandpiper (Calidris maritima) is a medium‐sized shorebird that breeds in the Arctic and winters along northern Atlantic coastlines. Migration routes and affiliations between breeding grounds and wintering grounds are incompletely understood. Some populations appear to be declining, and future management policies for this species will benefit from understanding their migration patterns. This study used two mitochondrial DNA markers and 10 microsatellite loci to analyze current population structure and historical demographic trends. Samples were obtained from breeding locations in Nunavut (Canada), Iceland, and Svalbard (Norway) and from wintering locations along the coast of Maine (USA), Nova Scotia, New Brunswick, and Newfoundland (Canada), and Scotland (UK). Mitochondrial haplotypes displayed low genetic diversity, and a shallow phylogeny indicating recent divergence. With the exception of the two Canadian breeding populations from Nunavut, there was significant genetic differentiation among samples from all breeding locations; however, none of the breeding populations was a monophyletic group. We also found differentiation between both Iceland and Svalbard breeding populations and North American wintering populations. This pattern of divergence is consistent with a previously proposed migratory pathway between Canadian breeding locations and wintering grounds in the United Kingdom, but argues against migration between breeding grounds in Iceland and Svalbard and wintering grounds in North America. Breeding birds from Svalbard also showed a genetic signature intermediate between Canadian breeders and Icelandic breeders. Our results extend current knowledge of Purple Sandpiper population genetic structure and present new information regarding migration routes to wintering grounds in North America.     

Phylogeography and population history of the endangered golden sun moth (Synemon plana) revealed by allozymes and mitochondrial DNA analysis

A combination of allozyme and mitochondrial DNA markers were used to determine the contribution of recent and ancient causes of patterns of genetic variation within and among 46 populations of the endangered golden sun moth, Synemon plana. Allozyme analysis grouped the 46 populations into 5 major genetic clusters that corresponded closely with geographic location following a classic isolation-by-distance model. Phylogenetic analysis of 14 mtDNA haplotypes revealed two reciprocally monophyletic groups. One of these groups (containing 4 geographically distant populations) was clearly identified by allozyme analysis and represents a distinct evolutionary unit. The remaining 4 allozyme groups were not distinguishable by mtDNA analysis. The evidence suggests that the populations within these groups derived from a small founding population that underwent rapid demographic expansion in ancient times. This was followed by more recent population bottlenecks resulting from habitat fragmentation associated with the widespread introduction of agriculture into the region. The generally low levels of allozyme and nucleotide diversity within these populations support this hypothesis. This revised version was published online in July 2006 with corrections to the Cover Date.     

Spatial patterns of plant diversity below-ground as revealed by DNA barcoding

Our understanding of the spatial organization of root diversity in plant communities and of the mechanisms of community assembly has been limited by our ability to identify plants based on root tissue, especially in diverse communities. Here, we test the effectiveness of the plastid gene rbcL, a core plant DNA barcoding marker, for investigating spatial patterns of root diversity, and relate observed patterns to above-ground community structure. We collected 3800 root fragments from four randomly positioned, 1-m-deep soil profiles (two vertical transects per plot), located in an old-field community in southern Ontario, Canada, and extracted and sequenced DNA from 1531 subsampled fragments. We identified species by comparing sequences with a DNA barcode reference library developed previously for the local flora. Nearly 85% of sampled root fragments were successfully sequenced and identified as belonging to 29 plant species or species groups. Root abundance and species richness varied in horizontal space and were negatively correlated with soil depth. The relative abundance of taxa below-ground was correlated with their frequency above-ground (r = 0.73, P = 0.0001), but several species detected in root tissue were not observed in above-ground quadrats. Multivariate analyses indicated that diversity was highly structured below-ground, and associated with depth, root morphology, soil chemistry and soil texture, whereas little structure was evident above-ground. Furthermore, analyses of species co-occurrence indicates strong species segregation overall but random co-occurrence among confamilials. Our results provide insights into the role of environmental filtering and competitive interactions in the organization of plant diversity below-ground, and also demonstrate the utility of barcoding for the identification of plant roots.     

Genetic lineages and postglacial colonization of grayling (Thymallus thymallus, Salmonidae) in Europe, as revealed by mitochondrial DNA analyses

In stark contrast to other species within the Salmonidae family, phylogeographic information on European grayling, Thymallus thymallus, is virtually nonexistent. In this paper, we utilized mitochondrial DNA polymerase chain reaction-restriction fragment length polymorphism (mtDNA PCR-RFLP) and sequence variation to infer the postglacial dispersal routes of T. thymallus into and within northern Europe, and to locate geographically, potential evolutionarily distinct populations. Mitochondrial analyses revealed a total of 27 T. thymallus haplotypes which clustered into three distinct lineages. Average pairwise interlineage divergence was four and nine times higher than average intralineage divergence for RFLP and sequence data, respectively. Two European grayling individuals from the easternmost sample in Russia exhibited haplotypes more genetically diverged from any T. thymallus haplotype than T. arcticus haplotype, and suggested that hybridization/introgression zone of these two sister species may extend much further west than previously thought. Geographic division of the lineages was generally very clear with northern Europe comprising of two genetically differentiated areas: (i) Finland, Estonia and north-western Russia; and (ii) central Germany, Poland and western Fennoscandia. Average interpopulation divergence in North European T. thymallus was 10 times higher than that observed in a recent mtDNA study of North American T. arcticus. We conclude that (i) North European T. thymallus populations have survived dramatic Pleistocene temperature oscillations and originate from ancient eastern and central European refugia; (ii) genetic divergence of population groups within northern Europe is substantial and geographically distinct; and (iii) the remainder of Europe harbours additional differentiated assemblages that likely descend from a Danubian refugium. These findings should provide useful information for developing appropriate conservation strategies for European grayling and exemplify a case with a clear need for multinational co-operation for managing and conserving biodiversity.     

Differentiation under isolation and genetic structure of Sardinian hares as revealed by craniometric analysis,mitochondrial DNA and microsatellites

Hares (Lepus capensis Linnaeus 1758) were probably introduced into Sardinia in historical times. Previous studies indicated North Africa as the most likely source area but did not exclude the occurrence of hybridization events with continental brown hares (L. europaeus Pallas 1778) perhaps introduced for hunting purposes. We implemented both morphometric and genetic approaches to verify the genetic isolation of the Sardinian population. Specifically, we conducted a multivariate analysis of craniometric data and analysed 461 bp of the mitochondrial control region and 12 autosomal microsatellites in Sardinian hares, using North African cape hares and European brown hares as reference populations. Sardinian hares displayed a peculiar skull shape. In agreement, both nuclear and mitochondrial markers remarked the distinctiveness of this population. Observed and expected heterozygosity were 0.52 and 0.61, while haplotype and nucleotide diversity were 0.822 and 0.0129. Self‐assignment based on Bayesian cluster analysis was high (average membership 0.98), and no evident signs of introgression from continental brown hares were found. Our results support the hypothesis that the Sardinian hares have been introduced from North Africa, remained genetically isolated since the founding event and evolved independently from the source population. This long‐lasting isolation and the consequent genetic drift resulted in a differentiation, perhaps accompanied by an adaptation to local environmental conditions.     

Phylogeography, intraspecific structure and sex-biased dispersal of Dall's porpoise, Phocoenoides dalli, revealed by mitochondrial and microsatellite DNA analyses

Mitochondrial DNA (mtDNA) control-region sequences and microsatellite loci length polymorphisms were used to estimate phylogeographical patterns (historical patterns underlying contemporary distribution), intraspecific population structure and gender-biased dispersal of Phocoenoides dalli dalli across its entire range. One-hundred and thirteen animals from several geographical strata were sequenced over 379 bp of mtDNA, resulting in 58 mtDNA haplotypes. Analysis using F(ST) values (based on haplotype frequencies) and phi(ST) values (based on frequencies and genetic distances between haplotypes) yielded statistically significant separation (bootstrap values P < 0.05) among most of the stocks currently used for management purposes. A minimum spanning network of haplotypes showed two very distinctive clusters, differentially occupied by western and eastern populations, with some common widespread haplotypes. This suggests some degree of phyletic radiation from west to east, superimposed on gene flow. Highly male-biased migration was detected for several population comparisons. Nuclear microsatellite DNA markers (119 individuals and six loci) provided additional support for population subdivision and gender-biased dispersal detected in the mtDNA sequences. Analysis using F(ST) values (based on allelic frequencies) yielded statistically significant separation between some, but not all, populations distinguished by mtDNA analysis. R(ST) values (based on frequencies of and genetic distance between alleles) showed no statistically significant subdivision. Again, highly male-biased dispersal was detected for all population comparisons, suggesting, together with morphological and reproductive data, the existence of sexual selection. Our molecular results argue for nine distinct dalli-type populations that should be treated as separate units for management purposes.     

基于粪便DNA的雪豹种群调查和遗传多样性

雪豹 (Panthera uncia) 是仅分布于亚洲高海拔山区的珍稀濒危猫科动物.本研究在印度西南部(Ladakh)、中国青海和蒙古国的南部(南Gobi)3个独立的雪豹分布区共采集109份粪便样品.应用线粒体DNA(mtDNA) cyt b基因特异性引物对109份粪便样品进行鉴定,发现有31份粪便来自雪豹,其中印度Ladakh、我国青海和蒙古国南Gobi的雪豹样品分别为17份、3份和11份.利用重新筛选设计的7对家猫(Felis catus)微卫星引物,对雪豹粪便样品进行了基因分型分析,结果发现在Ladakh和南Gobi检测到的雪豹粪便样品分别来自4只和5只不同的雪豹个体,而青海的样品则来自同一只雪豹;遗传多样性统计分析表明,蒙古国南Gobi的雪豹微卫星遗传多样性水平低于印度的Ladakh.研究结果表明了粪便DNA在雪豹种群监测和遗传多样性研究中的可行性.     

多基因联合揭示海南鲌的遗传结构与遗传多样性

海南鲌(Culter recurviceps)是我国华南地区重要经济鱼类, 由于受到近些年水利开发、过度捕捞、环境污染等诸多因素的影响, 其资源量快速下降, 亟需得到更多的关注和保护。为保护和合理开发海南鲌种质资源, 本研究采集了华南地区23个地理群体207尾海南鲌样本, 测定了2个线粒体基因(Cytb和ND2)并从Barcode of Life Data System数据库获得相对应线粒体COI基因, 结合多种分析方法(系统发育分析、分化时间估算、单倍型网状图、群体遗传分析和Mantel检验)对海南鲌的遗传结构和遗传多样性展开研究。系统发育分析和单倍型网状图表明华南地区海南鲌群体被分成3个谱系(I、II和III), 其中谱系I和III由珠江的群体组成, 谱系II由海南岛的群体组成。分化时间估算发现3个谱系之间的分化时间介于0.028-0.251 Ma之间, 表明华南地区更新世气候变化可能是造成海南鲌谱系分化的重要原因。群体遗传分析发现海南鲌群体之间存在极显著的遗传分化(F_ST = 0.511, P < 0.001), 并且符合距离隔离模式(R = 0.348, P = 0.0010)。群体动态历史分析表明, 海南鲌群体可能在0.010-0.025 Ma经历了群体扩张, 表明更新世的气候波动也影响了海南鲌的群体大小和分布。综上所述, 海南鲌群体由3个谱系组成, 更新世气候变化是导致3个谱系分化和影响海南鲌群体动态历史的重要因素。此外, 海南鲌群体之间的遗传分化也可能受到了空间距离的影响。     

Distribution of genetic diversity in Pinus pinaster Ait. as revealed by chloroplast microsatellites

 Using nine chloroplast simple sequence.repeats (cpSSRs) markers, we evaluated haplotypic variation within and among natural populations of Maritime pine (Pinus pinaster Ait.) in order to shed light on the history of this species. Seven out of the nine cpSSRs analysed were polymorphic, giving a total of 24 different variants. The 24 variants combined in 34 different haplotypes. The populations which generally showed the lowest level of haplotypic diversity are those located in Portugal. The Landes (France) and Pantelleria (Italy) populations represent the two main reservoirs of haplotypic diversity. The proportion of genetic differentiation among populations, estimated using R_st, which is a measure based upon a strict stepwise mutation model, was 0.235. The high level of differentiation was also confirmed by the AMOVA analysis (Φ_ST=0.254, P<0.001). Four main groups of populations were identified on the basis of Principal Component Analysis, with the differences being statistically significant (Φ_CT=0.299, P<0.001). Based on our results the presence of refugia located in the South of Portugal, previously proposed for this species, may be excluded, and a different possible recolonization process of Maritime pine in the post-glacial period has been proposed. Populations from North Africa and France might have represented a starting point of the recolonization process of Portugal and of the Italian part of the natural range, respectively. This hypothesis seems to be confirmed by the analysis of the distribution of the pairwise differences among individuals within populations: Landes and Pantelleria populations showed a bimodal distribution, as would be expected for ancient gene pools. Received: 5 November 1997 / Accepted: 5 January 1998     

The genetic diversity of planktic foraminifera and the global distribution of ribosomal RNA genotypes

Fossil planktic foraminifers in the ocean sediments play an unparalleled role in our understanding of the oceanographic environment in the past. An in depth knowledge of their diversity, ecology and biogeography in the modern ocean lies central to the interpretation of the fossil assemblages. In comparison with their benthic counterparts, planktic foraminifera have a very limited diversity of around fifty extant morphospecies. Their morphospecies diversity peaks in the sub-tropics and decreases steeply towards the poles. Traditional species concepts have partitioned morphological types into distinct species (morphospecies) based on test shape, but genetic studies show that individual morphospecies are actually complexes of several discrete genetic types (genotypes). Many of these genotypes have distinct ecologies and novel adaptations that are consistent with species-level classification, indicating that the true diversity of planktic foraminifers has been greatly underestimated. Although planktic foraminifera are clearly capable of long-distance dispersal, they may be constrained by both physical and ecological barriers that vary according to the evolutionary history and ecology of the individual genotypes within a morphospecies. These differences lead to diverse biogeographies. Here, we provide an overview of the genetic and biogeographic data available to date for the planktic foraminifera and present global biogeographies highlighting the distribution of genetic types in the eight planktic foraminiferal morphospecies for which detailed molecular evidence is available.