Cistaceae are shrubs, subshrubs and herbs that often occur in stressful, fire-prone or disturbed environments and form ectomycorrhizal (ECM) associations with symbiotic fungi. Although some Cistaceae are long-lived shrubs that grow to significant size, others are herbaceous annuals or short-lived plants. Thus, Cistaceae are atypical ECM hosts that are fundamentally different in their biology from trees that are the more typically studied ECM hosts.
View Article and Find Full Text PDFObjectives: Sex-specific genetic structures have been previously documented worldwide in humans, even though causal factors have not always clearly been identified. In this study, we investigated the impact of ethnicity, geography and social organization on the sex-specific genetic structure in Inner Asia. Furthermore, we explored the process of ethnogenesis in multiple ethnic groups.
View Article and Find Full Text PDFTwo sexual systems are predominant in Catasetinae (Orchidaceae), namely protandry (which has evolved in other orchid lineages as well) and environmental sex determination (ESD) being a unique trait among Orchidaceae. Yet, the lack of a robust phylogenetic framework for Catasetinae has hampered deeper insights in origin and evolution of sexual systems. To investigate the origins of protandry and ESD in Catasetinae, we sequenced nuclear and chloroplast loci from 77 species, providing the most extensive data matrix of Catasetinae available so far with all major lineages represented.
View Article and Find Full Text PDFEarlier research has revealed that the ndh loci have been pseudogenized, truncated, or deleted from most orchid plastomes sequenced to date, including in all available plastomes of the two most species-rich subfamilies, Orchidoideae and Epidendroideae. This study sought to resolve deeper-level phylogenetic relationships among major orchid groups and to refine the history of gene loss in the ndh loci across orchids. The complete plastomes of seven orchids, Oncidium sphacelatum (Epidendroideae), Masdevallia coccinea (Epidendroideae), Sobralia callosa (Epidendroideae), Sobralia aff.
View Article and Find Full Text PDFEvenks and Evens, Tungusic-speaking reindeer herders and hunter-gatherers, are spread over a wide area of northern Asia, whereas their linguistic relatives the Udegey, sedentary fishermen and hunter-gatherers, are settled to the south of the lower Amur River. The prehistory and relationships of these Tungusic peoples are as yet poorly investigated, especially with respect to their interactions with neighbouring populations. In this study, we analyse over 500 complete mtDNA genome sequences from nine different Evenk and even subgroups as well as their geographic neighbours from Siberia and their linguistic relatives the Udegey from the Amur-Ussuri region in order to investigate the prehistory of the Tungusic populations.
View Article and Find Full Text PDFThe great majority of plant species in the tropics require animals to achieve pollination, but the exact role of floral signals in attraction of animal pollinators is often debated. Many plants provide a floral reward to attract a guild of pollinators, and it has been proposed that floral signals of non-rewarding species may converge on those of rewarding species to exploit the relationship of the latter with their pollinators. In the orchid family (Orchidaceae), pollination is almost universally animal-mediated, but a third of species provide no floral reward, which suggests that deceptive pollination mechanisms are prevalent.
View Article and Find Full Text PDFBurkina Faso is located in the heart of West Africa and is a representative of the local structured patterns of human variability. Here, different cultures and languages are found in a geographic contiguity, as a result of several waves of migration and the succession of long- and short-term empires. However, historical documentation for this area is only partial, focusing predominantly on the recent empires, and linguistic surveys lack the power to fully elucidate the social context of the contact-induced changes.
View Article and Find Full Text PDFHistoric DNA data have the potential to identify phenotypic information otherwise invisible in the historical, archaeological and palaeontological record. In order to determine whether a single nucleotide polymorphism typing protocol based on single based extension (SNaPshot™) could produce reliable phenotypic data from historic samples, we genotyped three coat colour markers for a sample of historic Thoroughbred horses for which both phenotypic and correct genotypic information were known from pedigree information in the General Stud Book. Experimental results were consistent with the pedigrees in all cases.
View Article and Find Full Text PDFTechnological and cultural innovations as well as climate changes are thought to have influenced the diffusion of major language phyla in sub-Saharan Africa. The most widespread and the richest in diversity is the Niger-Congo phylum, thought to have originated in West Africa ∼ 10,000 years ago (ya). The expansion of Bantu languages (a family within the Niger-Congo phylum) ∼ 5,000 ya represents a major event in the past demography of the continent.
View Article and Find Full Text PDFBackground: To utilize the power of high-throughput sequencers, target enrichment methods have been developed. The majority of these require reagents and equipment that are only available from commercial vendors and are not suitable for the targets that are a few kilobases in length.
Methodology/principal Findings: We describe a novel and economical method in which custom made long-range PCR products are used to capture complete human mitochondrial genomes from complex DNA mixtures.
Background And Aims: Laeliinae are a neotropical orchid subtribe with approx. 1500 species in 50 genera. In this study, an attempt is made to assess generic alliances based on molecular phylogenetic analysis of DNA sequence data.
View Article and Find Full Text PDFBackground: Floral morphology, particularly the angle of lip attachment to the column, has historically been the fundamental character used in establishing generic limits in subtribe Oncidiinae (Orchidaceae), but it has also been long recognized that reliance on this character alone has produced a highly artificial set of genera. In essence, lip/column relationships reflect syndromes associated with pollinator preferences; most genera of Oncidiinae as previously defined have consisted of a single floral type. Here, the degree to which this has influenced generic delimitation in Brazilian members of the largest genus of Oncidiinae, Oncidium, which previous molecular (DNA) studies have demonstrated to be polyphyletic, is evaluated.
View Article and Find Full Text PDFBackground And Aims: The orchid genus Dichaea, with over 100 species found throughout the neotropics, is easily recognized by distichous leaves on long stems without pseudobulbs and flowers with infrastigmatic ligules. The genus has previously been divided into four sections based primarily on presence of ovary bristles and a foliar abscission layer. The aim of this work is to use DNA sequence data to estimate phylogenetic relationships within Dichaea and map the distribution of major morphological characters that have been used to delimit subgenera/sections.
View Article and Find Full Text PDFBackground And Aims: Species' boundaries applied within Christensonella have varied due to the continuous pattern of variation and mosaic distribution of diagnostic characters. The main goals of this study were to revise the species' delimitation and propose a more stable classification for this genus. In order to achieve these aims phylogenetic relationships were inferred using DNA sequence data and cytological diversity within Christensonella was examined based on chromosome counts and heterochromatin patterns.
View Article and Find Full Text PDFThe orchid genus Maxillaria is one of the largest and most common of neotropical orchid genera, but its current generic boundaries and relationships have long been regarded as artificial. Phylogenetic relationships within subtribe Maxillariinae sensu Dressler (1993) with emphasis on Maxillaria s.l.
View Article and Find Full Text PDFAs currently defined, the 24 species of Schoenocaulon occur in three disjunct areas: north central Florida (one species, S. dubium), southern Peru (portion of the range of S. officinale), and the region from southeastern New Mexico-Texas south to Venezuela; the 20 species endemic to Mexico are geographically restricted.
View Article and Find Full Text PDFMembers of tribe Vandeae (Orchidaceae) form a large, pantropical clade of horticulturally important epiphytes. Monopodial leafless members of Vandeae have undergone extreme reduction in habit and represent a novel adaptation to the canopy environment in tropical Africa, Asia, and America. To study the evolution of monopodial leaflessness, molecular and structural evidence was used to generate phylogenetic hypotheses for Vandeae.
View Article and Find Full Text PDFBackground And Aims: Within Oncidiinae, there are several groups of species that are effectively annuals, and we wished to see if these species had smaller genome sizes than average for the subtribe.
Methods: Fifty-four genome size estimates (50 of which are new) for species in subtribe Oncidiinae (Orchidaceae) were examined for the first time in a phylogenetic context to evaluate hypotheses concerning genome sizes and life history traits.
Results And Conclusions: Within the limits of still relatively sparse sampling, the species that are effectively annuals do appear to have smaller genome sizes than average.