Phylogeny of freshwater crayfish

The phylogeny of freshwater crayfish, including both fossil and extant taxa, is assessed using morphologic analysis and nucleotide sequencing. Based on external morphologic characters, primarily characters of the carapace and appendages, the crayfish are reconfirmed as a monophyletic group. The nearest sister taxon to the crayfish is the Chilenophoberidae. Within the crayfish, the longstanding distribution of species among three families is supported. The superfamily Astacoidea is redefined to include three families, Astacidae, Cambaridae, and Parastacidae. By including the Parastacidae in the Astacoidea, the superfamily Parastacoidea becomes superfluous and is now suppressed. The Astacoidea is characterized by several synapomorphies: a diaresis of the telson, mobility of the last thoracic segment, and carapace groove pattern. Species in the Parastacidae are characterized by change in calcification of the telson. Species in the Cambaridae are characterized by the apomorphous annulus ventralis in the female and hooks on the ichiopodites of one or more pereiopods in the male. Species in the Astacidae are characterized by an apomorphous medial rostral ridge. Nucleotide sequencing (18s and 16s ribosomal mtDNA) of extant crayfish species supports the phylogenetic pattern inferred from character analysis.No embarg

A field-based analysis of the accuracy of niche models applied to the fossil record

The use of ecological niche modeling (ENM) to estimate the geographic ranges of species is widely employed with modern fauna and is becoming more widespread in paleontology. Herein, field validation is utilized to assess the predictive accuracy of ENM methods for Paleozoic brachiopod species. This study represents the first field validation analysis of ENM methods in the fossil record. Previously published species distributions models for 8 Late Ordovician brachiopod species from the Cincinnati, Ohio region (United States) developed using GARP (Genetic Algorithm using Rule-set Prediction) were assessed for accuracy by comparing species occurrence data from a newly available set of 18 localities with the original species distribution models. Based on this data, the statistical significance of the original model set was assessed; 18 of the 22 original models were demonstrated to be statistically significant, based on field validation. Of the 140 individual species occurrences assessed, 60.8% were accurately predicted, 9.2% exhibited over prediction, and 30% exhibited under prediction. Accurate results were more common for species modeled from the greatest number of species occurrence points. The least accurate species models developed were for eurytopic species or those for which taxonomic affinities are unclear. Results indicate that with ample outcrop, well-defined stratigraphy, and sufficient fossil occurrence data, ENM methods could be successfully applied to many intervals in Earth history

Dispersal in the Ordovician: Speciation patterns and paleobiogeographic analyses of brachiopods and trilobites

The Middle to Late Ordovician was a time of profound biotic diversification, paleoecological change, and major climate shifts. Yet studies examining speciation mechanisms and drivers of dispersal are lacking. In this study, we use Bayesian phylogenetics and maximum likelihood analyses in the R package BioGeoBEARS to reanalyze ten published data matrices of brachiopods and trilobites and produce time-calibrated species-level phylogenetic hypotheses with estimated biogeographic histories. Recovered speciation and biogeographic patterns were examined within four time slices to test for changes in speciation type across major tectonic and paleoclimatic events. Statistical model comparison showed that biogeographic models that incorporate long-distance founder-event speciation best fit the data for most clades, which indicates that this speciation type, along with vicariance and traditional dispersal, were important for Paleozoic benthic invertebrates. Speciation by dispersal was common throughout the study interval, but notably elevated during times of climate change. Vicariance events occurred synchronously among brachiopod and trilobite lineages, indicating that tectonic, climate, and ocean processes affected benthic and planktotrophic larvae similarly. Middle Ordovician inter-oceanic dispersal in trilobite lineages was influenced by surface currents along with volcanic island arcs acting as “stepping stones” between areas, indicating most trilobite species may have had a planktic protaspid stage. These factors also influenced brachiopod dispersal across oceanic basins among Laurentia, Avalonia, and Baltica. These results indicate that gyre spin-up and intensification of surface currents were important dispersal mechanisms during this time. Within Laurentia, surface currents, hurricane tracks, and upwelling zones controlled dispersal among basins. Increased speciation during the Middle Ordovician provides support for climatic facilitators for diversification during the Great Ordovician Biodiversification Event. Similarly, increased speciation in Laurentian brachiopod lineages during the Hirnantian indicates that some taxa experienced speciation in relation to major climate changes. Overall, this study demonstrates the substantial power and potential for likelihood-based methods for elucidating biotic patterns during the history of life.This study was supported by NSF (EF-1206750, EAR-0922067 to A.L.S.) and the Dry Dredgers Paleontological Research Award, the Paleontological Society Arthur J. Boucot Award, and an Ohio University Graduate Alumni Research Grant to A.R.L. N.J.M. was supported by Discovery Early Career Researcher Award (DECRA) DE150101773, funded by the Australian Research Council, and by The Australian National University. He was also supported by the National Institute for Mathematical and Biological Synthesis (NIMBioS), an Institute sponsored by the National Science Foundation, the U.S. Department of Homeland Security, and the U.S. Department of Agriculture through NSF Awards #EFJ0832858 and DBI-1300426, with additional support from The University of Tennessee, Knoxville. In addition, a NIMBioS short-term visitor award allowed A.R.L. to visit NIMBioS to begin collaboration with N.J.M. This is a contribution to the International Geoscience Programme (IGCP) Projects 591- The Early to Middle Paleozoic Revolution and 653- The Onset of the Great Ordovician Biodiversification Event

Developing a phylogenetic framework for tiny Ordovician brachiopods (Atrypida: Anazyginae and Catazyginae) from the eastern United States

Elucidating how environmental change can facilitate the differentiation of evolutionary lineages and the establishment of new species is a critical issue for understanding both the history of life and modern biota. Notably, speciation events are known to be the main drivers of biodiversification; thus, generating well-constrained phylogenetic hypotheses to investigate speciation processes and facilitators can provide key data on links between biogeography, speciation, and diversification. During the Great Ordovician Biodiversification Event (GOBE), articulate brachiopods were a key group on the rise. By the Middle to Late Ordovician, the brachiopod order Atrypida was no exception. The atrypids diversified greatly and established evolutionary novelties such as helical and calcite-supported lophophores. The Ordovician epicontinental seas in eastern Laurentia provided an excellent environment for reproductive isolation and speciation, with sea-level fluctuations, ideal climate conditions, and active tectonic settings. However, speciation patterns and drivers within two widely-distributed atrypid subfamilies, Anazyginae (Anazyga spp. and Zygospira spp.) and Catazyginae (Catazyga spp.), remain poorly known. In this project, we seek to develop a robust phylogenetic framework for these clades and use that framework to evaluate speciation processes and facilitators during the Late Ordovician. Morphological data will be collected from published literature and museum collections for a target group of 18 species, five recently reviewed species of Zygospira, seven species of Anazyga, and five species assigned to Catazyga. Protozyga exigua will be included for outgroup comparison. Specimens will be assessed at the Smithsonian National Museum of Natural History, which houses the comprehensive Cooper Collection, and specimens loaned from other museums. A morphological matrix will be created using more than 40 characters, including both external and internal characters. The resulting character matrix will be analyzed via Bayesian phylogenetic inference using the MrBayes software package. The Bayesian framework assesses the posterior probability in a generated tree by incorporating likelihood models and uncertainties, such as data insufficiency. Hence, given the incompleteness of the nature of morphological data for these clades, Bayesian inference is an ideal and efficient method to reconstruct phylogenetic relationships. Speciation mode and biogeographic patterns will then be analyzed using the BioGeoBears software package. Through this process, we aim to understand the speciation relationships within a monophyletic clade (Anazyginae and Catazyginae) and ancestor forms. Systematic revision results in more precise species identities, through which it is possible to track character evolution within the genera. The results include (1) consistency in morphological traits within genera, such as shell ribs and the number of lophophore whorls, and (2) articulated differences among the three genera, evidencing derived states from a common ancestor. Combining phylogenetic and biogeographic analyses within the Atrypida provides essential information for understanding the impacts of geological and biotic changes on marine species across the Middle and Upper Ordovician. Thus, incorporating unique characters such as the number of whorls, shell ribs, and size in phylogenetic frameworks can elucidate evolutionary trends and phylogenetic relationships within the clade and provide evidence of how those factors impacted atrypidsâ distribution and abundance throughout the Paleozoic

Frontiers of Biogeography:Taking its place as a journal of choice for the publication of high quality biogeographical research articles

Through this editorial we seek your support and engagement as authors, readers and reviewers as we take the next steps in developing Frontiers of Biogeography as a leading international journal of biogeography and related subdisciplines. Here we make the case for submitting your next contribution to this journal: affordable, gold libre, open access, with the support of a disciplinarily-informed editorial and review team, which returns benefits to the biogeography community.Peer Reviewe

Diversification and speciation among Laurentian brachiopods during the GOBE: insights from basinal and regional analyses

Full understanding of diversity dynamics during the Great Ordovician Biodiversification Event (GOBE) requires analyses that investigate regional and species-level data and patterns. In this study, we combine bedding-plane scale data on brachiopod species counts and shell size col­lected from the Simpson Group of Oklahoma, USA, with species-level phylogenetic biogeography for three articulated brachiopod lineages that occurred throughout Laurentia. From these data, we ascertain that the primary influences of brachiopod shell size and diversity in the Simpson Group reflect global drivers, notably temporal position and paleotemperature. Similarly, the primary speciation pattern observed within Hesperorthis, Mimella, and Oepikina is the oscillation in speciation mode between dispersal and vicariance, which reflect the connection and disconnection of geographic areas, respectively. Processes that facilitate cyclical connectivity are global to regional in scale such as oceanographic changes, glacial cycles, or tectonic pulses. Therefore, both regional and continental scale analyses reinforce the importance of global factors in driving diversification during the GOBE

Framing the future for taxonomic monography: Improving recognition, support, and access

No abstract available

Framing the future for taxonomic monography: Improving recognition, support, and access

Taxonomic monographs synthesize biodiversity knowledge and document biodiversity change through recent and geological time for a particular organismal group, sometimes also incorporating cultural and place-based knowledge. They are a vehicle through which broader questions about ecological and evolutionary patterns and processes can be generated and answered (e.g., Muñoz Rodríguez et al., 2019). Chiefly, monography represents the foundational research upon which all biological work is based (Hamilton et al., 2021). Moreover, monography can be a pathway to developing inclusive scientific practices, engaging diverse audiences in expanding and disseminating indigenous and local knowledge and significance of place. Apart from the scientific importance of monography, these comprehensive biodiversity treatments are also crucial for policy, conservation, human wellbeing, and the sustainable use of natural resources. Taxonomic, cultural and biodiversity data within monographs aid in the implementation of law and policy, such as the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), the Nagoya Protocol of the Convention on Biological Diversity (Buck & Hamilton, 2011), and the International Union for Conservation of Nature (IUCN) Red List (e.g., Neo et al., 2017). While vital as a knowledge resource and tool for conservation and research, monographs are not available for many groups of organisms. This is of particular concern for organisms that are threatened with extinction, of medical or economic importance, and those organisms that have the potential to provide insight into biodiversity change over time because they are most susceptible to global change. In discussing the future of collections-based systematics, researchers have highlighted the importance of updated monographic workflows, collaborative teams, and effective ways to educate and disseminate the results of monographs to the public and scientific community (e.g., Wen et al., 2015; Grace et al., 2021). Here, we discuss how improving recognition, support, and access can lead to greater inclusivity while promoting a more active, sustainable, and collaborative outlook for monographic research. </p

Invasive species and biodiversity crises: testing the link in the late devonian.

During the Late Devonian Biodiversity Crisis, the primary driver of biodiversity decline was the dramatic reduction in speciation rates, not elevated extinction rates; however, the causes of speciation decline have been previously unstudied. Speciation, the formation of new species from ancestral populations, occurs by two primary allopatric mechanisms: vicariance, where the ancestral population is passively divided into two large subpopulations that later diverge and form two daughter species, and dispersal, in which a small subset of the ancestral population actively migrates then diverges to form a new species. Studies of modern and fossil clades typically document speciation by vicariance in much higher frequencies than speciation by dispersal. To assess the mechanism behind Late Devonian speciation reduction, speciation rates were calculated within stratigraphically constrained species-level phylogenetic hypotheses for three representative clades and mode of speciation at cladogenetic events was assessed across four clades in three phyla: Arthropoda, Brachiopoda, and Mollusca. In all cases, Devonian taxa exhibited a congruent reduction in speciation rate between the Middle Devonian pre-crisis interval and the Late Devonian crisis interval. Furthermore, speciation via vicariance is almost entirely absent during the crisis interval; most episodes of speciation during this time were due to dispersal. The shutdown of speciation by vicariance during this interval was related to widespread interbasinal species invasions. The lack of Late Devonian vicariance is diametrically opposed to the pattern observed in other geologic intervals, which suggests the loss of vicariant speciation attributable to species invasions during the Late Devonian was a causal factor in the biodiversity crisis. Similarly, modern ecosystems, in which invasive species are rampant, may be expected to exhibit similar shutdown of speciation by vicariance as an outcome of the modern biodiversity crisis