Evolutionary Taxonomy Research Articles

Detection and Analysis of melanin pigment in the edible seed coat of some plants

Melanin is a dark phenolic substance present in plants, animals, and microorganisms. The role of melanin in plants is to offer protection against biotic and abiotic conditions. The other possible functions in plants are unknown. Studying the occurrence of melanin in plants is essential to understand the taxonomic evolution of plants and its application in different fields. The deposition and distribution of Phytomelanin in the seed coat was studied using a light microscopy The seed coats of Phaselous vulgaris (Leguminaceae), Vigna mungo (Fabaceae), Linum usitatissimum (Linaceae), Cicer arietinum (Fabaceae), Vigna unguiculata (Fabaceae), Sesamum indicum (padaliaceae) and Macrotylama uniflorum (Fabaceae) showed the presence of melanin. Among the plant studied, S. indicum and V. mungo had a higher yield of melanin per 5 g of seeds. Melanin was extracted, purified and a confirmatory test was also conducted. UV and FT-IR studies were carried out with purified melanin. V. mungo and P. vulgaris showed no absorbance in the UV spectrum. The Maximum absorbance was found at 276 nm for S. indicum, M. uniflorum at 283 nm, L. usitatissimum at 276.5 nm, and V. unguiculata at 286 nm. It is evident from the study that phytomelanin is present in higher concentrations in S. indicum followed by V. mungo.

Specialized metabolites of the genus Zephyranthes Herb.: a critical review on taxonomy and phytochemistry

AbstractThis article is a critical review of the taxonomy and phytochemistry of the genus Zephyranthes Herb., a group of plants known for their beautiful flowers and traditional medicinal uses. The present review summarizes the occurrence, isolation, and identification of specialized metabolites, which have recently been frequently studied because of their important biological activities. Among the accepted 203 species, only 27 have been phytochemically investigated. This paper provides an overview of the different types of specialized metabolites identified in these plants and considers problematic taxonomic evolution within this species. The differences between two internationally recognized databases, which classify only 41% of the species in the same way, are briefly summarized. In addition, there are many reports on their metabolites, especially alkaloids, but some of the data in the literature are occasionally inaccurate and sometimes even erroneous. This critical review aims to discuss, summarize, and evaluate up-to-date (up to July of 2023) information about metabolites of the genus Zephyranthes, focusing on phytochemistry and taxonomy. Graphical abstract

Mycetoma in Animals a Review of Cases Reported From 1925-2022; Epidemiology and Management Strategies

Mycetoma is a chronic, granulomatous disease of human and various domestic animals caused by diverse causative agents. Recently, this mycosis has gained bad reputation due to the appearance of new endemic areas, recognition of new pathogenic species, changes in epidemiology, and increasing numbers of cases. The etiological agents in eumycetoma seem to be differ in human and animals. For example, _Madurella mycetomatis _are most common species in humans but only two cases have been reported in animal. While in animals the most common agents were _Pseudallescheria boydii._ However, there are few case reports and studies in animals compared to those in humans especially in endemic areas. Considering the epidemiological importance, taxonomic evolution and worldwide distribution of these fungi in the last decade, there is interest in identifying the species causing mycetoma in animals in different regions of the world. The present article only highlights on the geographic distribution of animal mycetoma in the world as well as the development and epidemiology of antifungal treatment in animals will also be discussed.

Cenozoic comparisons of diversity and disparity in the context of tectonic regime: A case study in North American rodents

The tectonic evolution of landscape topography is an important driver of biotic evolution throughout Earth's history. Studies of extant diversity have shown a higher diversity of mammals in topographically complex regions, suggesting that landscape complexity plays a role in generating taxonomic diversity. However, this relationship is poorly understood, especially over geologic time scales. Previous work has posited that heterogeneous topography should lead to increased species diversity as a result of new niche spaces into which lineages may speciate. This is in comparison to homogeneous landscape topography, which offers fewer and less varied niche spaces and thus less ecological opportunities for diversification. It is also thought that barriers to species and individual movement created by mountainous landscapes may divide populations, leading to speciation by restricting gene flow. These two models can be distinguished by their effects on morphological disparity. If niche differentiation is important to the process, we would expect increased morphological disparity in association with heterogeneous landscape topography, whereas the allopatry model predicts no greater morphological disparity over the complex landscape, only taxonomic diversification. We explore these models in the tectonically active and passive regions of North America in rodents from 25 to 0 Ma. We investigate diversity and disparity trends and examine the effects of climate, landscape heterogeneity, and environmental shifts on these patterns. We find that morphological and taxonomic evolution are not impacted by topography in a predictable way, and find that homogeneous landscapes host taxonomic and morphological diversity surpassing that of heterogeneous landscapes for much of the last 19 million years in North America. Furthermore, diversity and disparity trends are both coupled and decoupled during this period, signifiying that taxonomic and morphologic increase and decrease are discordant through time. Our results support the finding that the relationship between landscape heterogeneity and species diversity has not remained constant through geologic time.

Scaling of Protein Function across the Tree of Life.

Scaling laws are a powerful way to compare genomes because they put all organisms onto a single curve and reveal nontrivial generalities as genomes change in size. The abundance of functional categories across genomes has previously been found to show power law scaling with respect to the total number of functional categories, suggesting that universal constraints shape genomic category abundance. Here, we look across the tree of life to understand how genome evolution may be related to functional scaling. We revisit previous observations of functional genome scaling with an expanded taxonomy by analyzing 3,726 bacterial, 220 archaeal, and 79 unicellular eukaryotic genomes. We find that for some functional classes, scaling is best described by multiple exponents, revealing previously unobserved shifts in scaling as genome-encoded protein annotations increase or decrease. Furthermore, we find that scaling varies between phyletic groups at both the domain and phyla levels and is less universal than previously thought. This variability in functional scaling is not related to taxonomic phylogeny resolved at the phyla level, suggesting that differences in cell plan or physiology outweigh broad patterns of taxonomic evolution. Since genomes are maintained and replicated by the functional proteins encoded by them, these results point to functional degeneracy between taxonomic groups and unique evolutionary trajectories toward these. We also find that individual phyla frequently span scaling exponents of functional classes, revealing that individual clades can move across scaling exponents. Together, our results reveal unique shifts in functions across the tree of life and highlight that as genomes grow or shrink, proteins of various functions may be added or lost.

Predicting Moffitt's Developmental Taxonomy of Antisocial Behavior Using Life History Theory: A Partial Test of the Evolutionary Taxonomy.

Evolutionary criminology is an approach to the understanding of crime and criminality that is based in part on key aspects of evolutionary psychology. The approach allows for a renewed examination of traditional criminological assumptions and can serve to further enhance theoretical viewpoints on antisocial behavior. The recently developed evolutionary taxonomy theory is an example of such an approach. Relying on the tenets of life history theory, the evolutionary taxonomy was proposed as a theoretical scaffolding for Moffitt's developmental taxonomy of offending. While recent tests of the evolutionary taxonomy have been informative, lacking from the existing literature is an assessment of the extent to which measures of life history theory can predict classification into offending groups based on Moffitt's developmental taxonomy. The current study provided a partial test of classification predictions using the National Longitudinal Study of Adolescence to Adult Health study (n = 12,012). Results of multivariable regression analyses indicated that measures associated with somatic effort and aspects of the developmental environment were predictive of group classification, but measures associated with reproductive effort were not. Implications for evolutionary criminology and traditional criminology are discussed.

The Past Is Present: Co-Evolution of Viruses and Host Resistance Within Geographic Centers of Plant Diversity.

Understanding the coevolutionary history of plants, pathogens, and disease resistance is vital for plant pathology. Here, I review Francis O. Holmes's work with tobacco mosaic virus (TMV) framed by the foundational work of Nikolai Vavilov on the geographic centers of origin of plants and crop wild relatives (CWRs) and T. Harper Goodspeed's taxonomy of the genus Nicotiana. Holmes developed a hypothesis that the origin of host resistance to viruses was due to coevolution of both at a geographic center. In the 1950s, Holmes proved that genetic resistance to TMV, especially dominant R-genes, was centered in South America for Nicotiana and other solanaceous plants, including Capsicum, potato, and tomato. One seeming exception was eggplant (Solanum melongena). Not until the acceptance of plate tectonics in the 1960s and recent advances in evolutionary taxonomy did it become evident that northeast Africa was the home of eggplant CWRs, far from Holmes's geographic center for TMV-R-gene coevolution. Unbeknownst to most plant pathologists, Holmes's ideas predated those of H.H. Flor, including experimental proof of the gene-for-gene interaction, identification of R-genes, and deployment of dominant host genes to protect crop plants from virus-associated yield losses. Expected final online publication date for the Annual Review of Phytopathology, Volume 61 is September 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Use of an Integrated Approach Involving AlphaFold Predictions for the Evolutionary Taxonomy of Duplodnaviria Viruses.

The evaluation of the evolutionary relationships is exceptionally important for the taxonomy of viruses, which is a rapidly expanding area of research. The classification of viral groups belonging to the realm Duplodnaviria, which include tailed bacteriophages, head-tailed archaeal viruses and herpesviruses, has undergone many changes in recent years and continues to improve. One of the challenging tasks of Duplodnaviria taxonomy is the classification of high-ranked taxa, including families and orders. At the moment, only 17 of 50 families have been assigned to orders. The evaluation of the evolutionary relationships between viruses is complicated by the high level of divergence of viral proteins. However, the development of structure prediction algorithms, including the award-winning AlphaFold, encourages the use of the results of structural predictions to clarify the evolutionary history of viral proteins. In this study, the evolutionary relationships of two conserved viral proteins, the major capsid protein and terminase, representing different viruses, including all classified Duplodnaviria families, have been analysed using AlphaFold modelling. This analysis has been undertaken using structural comparisons and different phylogenetic methods. The results of the analyses mainly indicated the high quality of AlphaFold modelling and the possibility of using the AlphaFold predictions, together with other methods, for the reconstruction of the evolutionary relationships between distant viral groups. Based on the results of this integrated approach, assumptions have been made about refining the taxonomic classification of bacterial and archaeal Duplodnaviria groups, and problems relating to the taxonomic classification of Duplodnaviria have been discussed.

Net-Winged Midge Genus Blepharicera Macquart (Diptera: Blephariceridae) in China: The First DNA Barcode Database with Descriptions of Four New Species and Notes on Distribution.

Simple SummaryBlephariceridae is a small but highly specialized family in Diptera with extreme morphological adaptations for living in fast-moving waters. Among the seven blepharicerid genera in China, Blepharicera Macquart, 1843 is the species richest genus with 12 known species. There is a serious gap in knowledge concerning larval stages and connecting them to adult morphology. At present, DNA barcoding using mitochondrial (mt) cytochrome c oxidase subunit 1 gene (COI) has proven to be successful for identification in many animal groups. There are about 60 species of the genus Blepharicera known in the world. However, only one identified Blepharicera species from Europe is currently available in DNA sequence repositories, and a DNA barcode database is still lacking for Chinese Blepharicera. To fill this gap, we started a project with the objectives to collect specimens of Blepharicera across China, identify the species by morphological characters, and build an mt COI barcode database for this important insect group. Molecular and morphological markers show that four morphospecies examined represent members of the genus Blepharicera and constitute four new, distinct species. This initial attempt indicates the validity of mt COI barcodes for Blepharicera in delimiting species and contributes to the growing library of DNA barcodes of net-winged midges of the world.Mitochondrial (mt) cytochrome c oxidase 1 (COI) gene is more and more widely used for DNA barcoding, which provides a rapid and timely identification as this technique is not limited by polymorphism, sex, and life stages and fundamentally complements traditional evolutionary taxonomy. The present study generated 33 mt COI sequences of seven Chinese Blepharicera Macquart, 1843 species with an average of 594 bp, which represent the first DNA barcode database for Chinese Blepharicera. Genetic distance analysis reveals that intraspecific distances in the genus are generally less than 1.7%, and interspecific distances range from 5.4% to 20.3%. Phylogenetic analysis shows that each species recovered in our analyses is separated from all neighboring species. Based on molecular and morphological data, four Blepharicera species from China, B. beishanica sp. nov., B. dushanzica sp. nov., B. nigra sp. nov. and B. xinjiangica sp. nov., are described and illustrated as new to science. Identification keys for adults and larvae of Chinese Blepharicera are also presented. Geographical analysis shows that Southwest China is the species’ richest region. Our results will be useful in tackling taxonomic problems, understanding species distribution, and resolving nomenclature conflicts associated with Blepharicera species.

Global distribution of animal sporotrichosis: A systematic review of Sporothrix sp. identified using molecular tools.

Sporotrichosis is a subcutaneous mycosis caused by thermodimorphic fungi of the genus Sporothrix. The phenotypic and genotypic differences of the isolates within the genus Sporothrix have been associated with their geographic distribution, virulence capacity, or clinical manifestation of sporotrichosis. Therefore, it is crucial to identify the causative agent of sporotrichosis. However, there are few case reports and studies in animals compared to those in humans, despite the substantial increase in the number of cases of sporotrichosis by zoonotic transmission, especially in endemic areas. Considering the epidemiological importance, taxonomic evolution and worldwide distribution of these fungi in the last decade, there is interest in identifying the species of the genus Sporothrix in different regions of the world. This study aimed to analyze the geographic distribution of animal sporotrichosis in the world, caused by pathogenic species identified by use of molecular tools. This systematic review of articles from 2007 to 2021 analyzed the geographic distribution of species that cause sporotrichosis in cats, dogs and other animals. It demonstrated that the most identified species were S. brasiliensis, isolated from cats in Brazil and S. schenckii isolated from cats in Malaysia. We show the lack of studies in global areas and reinforce the need to use molecular tools to identify and monitor potential pathogens.

Species as a system within a system

The article presents the results of an analytical review of general laws of nature development and their relationships with the laws of biological evolution in terms of general theory of systems and their synergetic manifestation at different levels of organization. The basis of such analysis is the interpretation of the species as a system, as a structure with self-organizing and complicating abilities, as well as a unit of evolutionary diversity and taxonomy. At the same time, as a system, the species occupies an appropriate position in system subordination, in the hierarchy of biological evolution, and in systems of taxonomic division and phylogeny. Its synergistic connections in the system characterize its complexity, functionality, self-organization, and alternative development, which is manifested through saltation, relative balance and constant absorption of energy to organize chaos as a source of order. These characteristics accompany the non-integrated development of biological systems as open and unbalanced by intraspecific polymorphism. Analytical delineation of the species as a system within a system involves defining it as a structure, an element, and a carrier of properties and functions at different organizational (ontogenetic, biocoenotic, and evolutionary) levels of biological systems.

Folk Classification and Factor Rotations: Whales, Sharks, and the Problems With the Hierarchical Taxonomy of Psychopathology (HiTOP).

The Hierarchical Taxonomy of Psychopathology (HiTOP) uses factor analysis to group people with similar self-reported symptoms (i.e., like-goes-with-like). It is hailed as a significant improvement over other diagnostic taxonomies. However, the purported advantages and fundamental assumptions of HiTOP have received little, if any scientific scrutiny. We critically evaluated five fundamental claims about HiTOP. We conclude that HiTOP does not demonstrate a high degree of verisimilitude and has the potential to hinder progress on understanding the etiology of psychopathology. It does not lend itself to theory-building or taxonomic evolution, and it cannot account for multifinality, equifinality, or developmental and etiological processes. In its current form, HiTOP is not ready to use in clinical settings and may result in algorithmic bias against underrepresented groups. We recommend a bifurcation strategy moving forward in which the DSM is used in clinical settings while researchers focus on developing a falsifiable theory-based classification system.

Decoding first complete chloroplast genome of toothbrush tree (Salvadora persica L.): insight into genome evolution, sequence divergence and phylogenetic relationship within Brassicales

BackgroundSalvadora persica L. (Toothbrush tree – Miswak; family-Salvadoraceae) grows in the arid-land ecosystem and possesses economic and medicinal importance. The species, genus and the family have no genomic datasets available specifically on chloroplast (cp) genomics and taxonomic evolution. Herein, we have sequenced the complete chloroplast genome of S. persica for the first time and compared it with 11 related specie’s cp genomes from the order Brassicales.ResultsThe S. persica cp genome was 153,379 bp in length containing a sizeable single-copy region (LSC) of 83,818 bp which separated from the small single-copy region (SSC) of 17,683 bp by two inverted repeats (IRs) each 25,939 bp. Among these genomes, the largest cp genome size (160,600 bp) was found in M. oleifera, while in S. persica it was the smallest (153,379 bp). The cp genome of S. persica encoded 131 genes, including 37 tRNA genes, eight rRNA genes and 86 protein-coding genes. Besides, S. persica contains 27 forward, 36 tandem and 19 palindromic repeats. The S. persica cp genome had 154 SSRs with the highest number in the LSC region. Complete cp genome comparisons showed an overall high degree of sequence resemblance between S. persica and related cp genomes. Some divergence was observed in the intergenic spaces of other species. Phylogenomic analyses of 60 shared genes indicated that S. persica formed a single clade with A. tetracantha with high bootstrap values. The family Salvadoraceae is closely related to Capparaceae and Petadiplandraceae rather than to Bataceae and Koberliniacaea.ConclusionThe current genomic datasets provide pivotal genetic resources to determine the phylogenetic relationships, genome evolution and future genetic diversity-related studies of S. persica in complex angiosperm families.

Analysis of multiple chromosomal rearrangements in the genome of Willisornis vidua using BAC-FISH and chromosome painting on a supposed conserved karyotype

BackgroundThamnophilidae birds are the result of a monophyletic radiation of insectivorous Passeriformes. They are a diverse group of 225 species and 45 genera and occur in lowlands and lower montane forests of Neotropics. Despite the large degree of diversity seen in this family, just four species of Thamnophilidae have been karyotyped with a diploid number ranging from 76 to 82 chromosomes. The karyotypic relationships within and between Thamnophilidae and another Passeriformes therefore remain poorly understood. Recent studies have identified the occurrence of intrachromosomal rearrangements in Passeriformes using in silico data and molecular cytogenetic tools. These results demonstrate that intrachromosomal rearrangements are more common in birds than previously thought and are likely to contribute to speciation events. With this in mind, we investigate the apparently conserved karyotype of Willisornis vidua, the Xingu Scale-backed Antbird, using a combination of molecular cytogenetic techniques including chromosome painting with probes derived from Gallus gallus (chicken) and Burhinus oedicnemus (stone curlew), combined with Bacterial Artificial Chromosome (BAC) probes derived from the same species. The goal was to investigate the occurrence of rearrangements in an apparently conserved karyotype in order to understand the evolutionary history and taxonomy of this species. In total, 78 BAC probes from the Gallus gallus and Taeniopygia guttata (the Zebra Finch) BAC libraries were tested, of which 40 were derived from Gallus gallus macrochromosomes 1–8, and 38 from microchromosomes 9–28.ResultsThe karyotype is similar to typical Passeriformes karyotypes, with a diploid number of 2n = 80. Our chromosome painting results show that most of the Gallus gallus chromosomes are conserved, except GGA-1, 2 and 4, with some rearrangements identified among macro- and microchromosomes. BAC mapping revealed many intrachromosomal rearrangements, mainly inversions, when comparing Willisornis vidua karyotype with Gallus gallus, and corroborates the fissions revealed by chromosome painting.ConclusionsWillisornis vidua presents multiple chromosomal rearrangements despite having a supposed conservative karyotype, demonstrating that our approach using a combination of FISH tools provides a higher resolution than previously obtained by chromosome painting alone. We also show that populations of Willisornis vidua appear conserved from a cytogenetic perspective, despite significant phylogeographic structure.

Entandrophragma: taxonomy and ecology of a genus of African tree species with economic importance. A review

Introduction. Entandrophragma tree species have been the subject of special attention by foresters and scientists for several decades. The purpose of this bibliographic review is to examine the current knowledge acquired on the taxonomy and ecology of this genus in order to identify new research priorities. Literature. The genus Entandrophragma has exclusively African species (10 to 12) that are exploited for the quality of their wood. These species are widespread in the Guineo-Congolese region (6 species) and in the Zambezian and Afromontane regions (5 species). The genus is characterized by a taxonomic evolution that has resulted in an important synonymy of species names (36 to 37). Ecological studies have been carried out on some major commercial species (Entandrophragma angolense, Entandrophragma congoense, Entandrophragma candollei, Entandrophragma cylindricum, Entandrophragma palustre and Entandrophragma utile) in their phytogeographic zones, mainly in the Guineo-Congolese region. Conclusions. Taxonomy and ecology of Entandrophragma tree species typically occurring in woodlands and savannas have been insufficiently studied in comparison with Entandrophragma species occurring in rainforests. Research needs to be developed for the improvement of taxonomic, genetic and ecological knowledge, with a view to formulating appropriate recommendations for the conservation and sustainable management of these species.

The Main Lines of Research at the Botanical Garden of M. V. Lomonosov Moscow State University in 1937–1973

The Botanical Garden of M. V. Lomonosov Moscow State University is the oldest scientific botanical institution in Russia. Established in 1706 as a physic garden, it was acquired by Moscow University in 1805. This article reviews the dynamics of the range of research areas pursued by the Garden in 1937–1973 (from its becoming an autonomous institution within MSU to the splitting of Biological and Soil Science Faculty and the Garden becoming part of a recreated Biological Faculty). Based on the analysis of bibliography and materials of the theme plans and reports on the Garden’s research work, deposited at the MSU Archive, this time period may be divided into several stages. Thus, in 1937–1948, the research focused on the development of methods for experimental morphogenesis, designed do obtain new heritable forms (induced polyploidy, X-ray treatment of crop and ornamental plants (L. P. Breslavets-Krestovnikova); development of scientific foundation for horticulture (“green construction”) to expand the diversity of herbaceous ornamental plants (M. P. Nagibina); studies on plant development rhythms and factors (A. V. Kozhevnikov, I. G. Serebryakov). In 1948–1951, after the August VASKhNIL Session, the problems of vegetative hybridization prevailed while, in 1952–1957, the researchers’ attention was focused on the development of scientific basis for the construction of a new botanical garden as a component of natural science cluster of MSU on Leninskie (Vorobyovy) Gory (N. A. Bazilevskaya). In 1958–1964, the focus was shifted towards complex studies of the domestic flora. In 1967–1973, the garden’s main lines of research were evolutionary morphology, plant taxonomy, floristics, and botanical geography (A. K. Skvortsov, V. N. Tikhomirov); plant protection and agrochemistry; and breeding and genetics of ornamental plants and fruit and berry crops. Therefore, at different stages, the emphasis was placed on both the fundamental and applied research whose focus changed depending on the sociopolitical context of the epoch.

Prevalence of diversified antibiotic resistant bacteria within sanitation related facilities of human populated workplaces in Abbottabad.

Antibiotics discovery was a significant breakthrough in the field of therapeutic medicines, but the over (mis)use of such antibiotics (in parallel) caused the increasing number of resistant bacterial species at an ever-higher rate. This study was thus devised to assess the multi-drug resistant bacteria present in sanitation-related facilities in human workplaces. In this regard, samples were collected from different gender, location, and source-based facilities, and subsequent antibiotic sensitivity testing was performed on isolated bacterial strains. Four classes of the most commonly used antibiotics i.e., β-lactam, Aminoglycosides, Macrolides, and Sulphonamides, were evaluated against the isolated bacteria. The antibiotic resistance profile of different (70) bacterial strains showed that the antibiotic resistance-based clusters also followed the grouping based on their isolation sources, mainly the gender. Twenty-three bacterial strains were further selected for their 16s rRNA gene based molecular identification and for phylogenetic analysis to evaluate the taxonomic evolution of antibiotic resistant bacteria (ARB). Moreover, the bacterial resistance to Sulphonamides and beta lactam was observed to be the most and to Aminoglycosides and macrolides as the least. Plasmid curing was also performed for multidrug resistant (MDR) bacterial strains, which significantly abolished the resistance potential of bacterial strains for different antibiotics. These curing results suggested that the antibiotic resistance determinants in these purified bacterial strains are present on respective plasmids. Altogether, the data suggested that the human workplaces are the hotspot for the prevalence of MDR bacteria and thus may serve as the source of horizontal gene transfer and further transmission to other environments.

Popper as a process: revisiting the appropriation of the Popperian philosophy by the cladists during the “systematics wars”

The philosophy of Karl Popper was strongly used by the cladists in their battle against evolutionary and numerical taxonomy. It became known as “Systematics Wars” by David Hull. His historical account in Science as a Process, described the outcome of that era that end up with the victory of cladistics. Claiming it as hypothetico-deductivist, and falsificationist, cladists have transformed and distorted Popper, that almost nothing of these ideas survived scrutiny. One of the Hull’s conclusion was that the success of cladistics was largely due to their ability to maintain social cohesion and intellectual orthodoxy during the years of the Systematic Wars. In this paper, I will provide a concise historical development about the appropriation of Popper’s ideas that were used by systematics, both as a defense and as a critic, trying to make clear the interpretations of these authors in relation to Popper and their research program. Using David Hull’s General Theory of Selection Processes, I will argue that these facts were, partially, to a heavy adherence to Popper’s philosophy.

Evolution: Two Domains of Life or Three?

That Bacteria, Archaea and Eukarya (eukaryotes) represent three separate domains of Life, no one having evolved from within any other, has been taken as fact for three decades. Recent work shows this to be untrue. Eukarya arose from well within Archaea and are specifically related to newly discovered archaeal species with eukaryote-like features.

A review of mono- and bispecific genera of Amphibians worldwide

Monospecific and bispecific genera are of particular interest in studies of taxonomic diversity and speciation evolution. Here, the distribution patterns of mono- and bispecific amphibians worldwide are investigated, with some discussion of on the conservation implications also presented. Based on an online database search (available from the American Museum of Natural History, New York), we found that the mean number of mono- and bispecific genera was similar among zoogeographic regions, with a total of 120 mono- (95 Anura, 17 Caudata, 8 Gymnophiona) and 65 bispecific (48 Anura, 10 Caudata, 7 Gymnophiona) genera. Out of 73 known amphibian families worldwide, only 35.6 % of them do not contain any mono- or bispecific genera. The frequency of mono- or bispecific genera by family was not significantly different among Anura, Caudata and Gymnophiona. There was a general tendency for the number of mono- and bispecific genera of amphibians to be positively correlated with the total number of genera in that family. In Anura, there was a preponderance of mono-specific genera in Afrotropical and Neotropical regions. Concerning bispecific genera, there was a clear preponderance in the Neotropical region for anurans. There was a positive correlation between the number of threatened genera (according to the IUCN Red List) in both the mono- and bispecific groups and the relative number of species in each taxon, thus showing that taxonomical speciosity clearly influences the frequency of occurrence of mono- and bispecific taxa in each family and order. In this regard, Anura dominated in both the number of worldwide described mono- and bispecific taxa as well as in that of the threatened ones according to IUCN Red List .