Abstract. The field of systematics is experiencing a new molecular revolution driven by the increased availability of high-throughput sequencing technologies.

Abstract. We describe a new species of Polynesian sandpiper from Henderson Island, Prosobonia sauli sp. nov., based on multiple Holocene fossil bones collected

Objectives In 2013, the burials of 36 individuals of putative African ancestry were discovered during renovation of the Gaillard Center in downtown Charleston, South Carolina. The Charleston community facilitated a bioarchaeological and mitogenomic study to gain insights into the lives of these unknown persons, referred to as the Anson Street Ancestors, including their ancestry, health, and lived experiences in the 18th century. Methods Metric and morphological assessments of skeletal and dental characteristics were recorded, and enamel and cortical bone strontium stable isotope values generated. Whole mitochondrial genomes were sequenced and analyzed. Results Osteological analysis identified adults, both females and males, and subadults at the site, and estimated African ancestry for most individuals. Skeletal trauma and pathology were infrequent, but many individuals exhibited dental decay and abscesses. Strontium isotope data suggested these individuals mostly originated in Charleston or sub-Saharan Africa, with many being long-term residents of Charleston. Nearly all had mitochondrial lineages belonging to African haplogroups (L0-L3, H1cb1a), with two individuals sharing the same L3e2a haplotype, while one had a Native American A2 mtDNA. Discussion This study generated detailed osteobiographies of the Anson Street Ancestors, who were likely of enslaved status. Our results indicate that the Ancestors have diverse maternal African ancestries and are largely unrelated, with most being born locally. These details reveal the demographic impact of the trans-Atlantic slave trade. Our analysis further illuminates the lived experiences of individuals buried at Anson Street, and expands our understanding of 18th century African history in Charleston.

Key insights into the evolutionary history of recently extinct or critically endangered species can be obtained through analysis of genomic data collected using high-throughput sequencing and ancient DNA from museum specimens, particularly where specimens are rare. For instance, the evolutionary history of the critically endangered Puebla deer mouse, Peromyscus mekisturus, remains unclear due to discordance between morphological and molecular phylogenetic analyses. However, previous molecular analyses were based on PCR and Sanger sequencing of only a few mitochondrial genes. Here, we used ancient DNA from historical museum specimens followed by target enrichment and high-throughput sequencing of several thousand nuclear ultraconserved elements and whole mitochondrial genomes to test the validity of the previous phylogenetic placement of P. mekisturus. Based on UCEs and mitogenomes, our results revealed that P. mekisturus forms a well-supported distinct lineage outside the clade containing all other members of the Peromyscus melanophrys group. Additionally, the mitogenome phylogeny further supports the placement of P. mekisturus as the sister species of the genus Reithrodontomys. This conflicts with the previous mtDNA phylogenetic reconstruction, in which P. mekisturus was nested within the species P. melanophrys. Our study demonstrates that high-throughput sequencing of ancient DNA, appropriately controlling for contamination and degradation, can provide a robust resolution of the evolutionary history and taxonomic status of species for which few or no modern genetic samples exist. In light of our results and pending further analysis with denser taxon sampling and the addition of morphological data, a re-evaluation of the taxonomy and conservation management plans of P. mekisturus is needed to ensure that the evolutionary distinctiveness of this species is recognized in future conservation efforts.

Phylogenomics seeks to use next-generation data to robustly infer an organism’s evolutionary history. Yet, the practical caveats of phylogenomics motivate investigation of improved efficiency, particularly when quality of phylogenies are questionable. To achieve improvements, one goal is to maintain or enhance the quality of phylogenetic inference while severely reducing dataset size. We approach this by assessing which kinds of loci in phylogenomic alignments provide the majority of support for a phylogenetic inference of cockroaches in Blaberoidea. We examine locus substitution rate, saturation, evolutionary divergence, rate heterogeneity, stabilizing selection, and a priori information content as traits that may determine optimality. Our controlled experimental design is based on 265 loci for 102 blaberoidean taxa and 22 outgroup species. Loci with high substitution rate, low saturation, low sequence distance, low rate heterogeneity, and strong stabilizing selection derive more support for phylogenetic relationships. We found that some phylogenetic information content estimators may not be meaningful for assessing information content a priori. We use these findings to design concatenated datasets with an optimized subsample of 100 loci. The tree inferred from the optimized subsample alignment was largely identical to that inferred from all 265 loci but with less evidence of long branch attraction, improved statistical support, and potential 4-6x improvements to computation time. Supported by phylogenetic and morphological evidence, we erect three newly named clades (Anallactinae Evangelista & Wipfler subfam. nov., Orkrasomeria tax. nov. Evangelista, Wipfler, & Béthoux and Hemithyrsocerini Evangelista tribe nov.) and propose other taxonomic modifications. The diagnosis of Pseudophyllodromiidae Grandcolas, 1996 is modified to accommodate Anallactinae and Pseudophyllodromiinae Vickery & Kevan, 1983. The diagnosis of Ectobiidae Brunner von Wattenwyl, 1865 is modified to add novel morphological characters.

Cave adaptation has evolved repeatedly across the Tree of Life, famously leading to pigmentation and eye degeneration and loss, yet its macroevolutionary implications remain poorly understood. We use the North American amblyopsid fishes, a family spanning a wide degree of cave adaptation, to examine the impact of cave specialization on the modes and tempo of evolution. We reconstruct evolutionary relationships using ultraconserved element loci, estimate the ancestral histories of eye-state, and examine the impact of cave adaptation on body shape evolution. Our phylogenomic analyses provide a well-supported hypothesis for amblyopsid evolutionary relationships. The obligate blind cavefishes form a clade and the cave-facultative eyed spring cavefishes are nested within the obligate cavefishes. Using ancestral state reconstruction, we find support for at least two independent subterranean colonization events within the Amblyopsidae. Eyed and blind fishes have different body shapes, but not different rates of body shape evolution. North American amblyopsids highlight the complex nature of cave-adaptive evolution and the necessity to include multiple lines of evidence to uncover the underlying processes involved in the loss of complex traits. This article is protected by copyright. All rights reserved

Genetic structure in host species is often used to predict disease spread. However, host and pathogen genetic variation may be incongruent. Understanding landscape factors that have either concordant or divergent influence on host and pathogen genetic structuring is crucial for wildlife disease management. Devil facial tumor disease (DFTD) was first observed in 1996 and has spread throughout almost the entire Tasmanian devil geographic range, causing dramatic population declines. Whereas DFTD is predominantly spread via biting among adults, devils typically disperse as juveniles, which experience low DFTD prevalence. Thus, we predicted little association between devil and tumor population structure and that environmental factors influencing gene flow differ between devils and tumors. We employed a comparative landscape genetics framework to test the influence of environmental factors on patterns of isolation-by-resistance (IBR) and isolation-by-environment (IBE) in devils and DFTD. Although we found evidence for broad-scale co-structuring between devils and tumors, we found no relationship between host and tumor individual genetic distances. Further, the factors driving the spatial distribution of genetic variation differed for each. Devils exhibited a strong IBR pattern driven by major roads, with no evidence of IBE. By contrast, tumors showed little evidence for IBR and a weak IBE pattern with respect to elevation in one of two tumor clusters we identify herein. Our results warrant caution when inferring pathogen spread using host population genetic structure and suggest that reliance on environmental barriers to host connectivity may be ineffective for managing the spread of wildlife diseases. Our findings demonstrate the utility of comparative landscape genetics for identifying differential factors driving host dispersal and pathogen transmission.

Abstract. The adaptive radiations of East African cichlid fish in the Great Lakes Victoria, Malawi, and Tanganyika are well known for their diversity and repea

It is generally accepted that the spatial distribution of neutral genetic diversity within a species’ native range mostly depends on effective population size, demographic history, and geographic position. However, it is unclear how genetic diversity at adaptive loci correlates with geographic peripherality or with habitat suitability within the ecological niche. Using exome-wide genomic data and distribution maps of the Alpine range, we first tested whether geographic peripherality correlates with four measures of population genetic diversity at >17,000 SNP loci in 24 Alpine populations (480 individuals) of Swiss stone pine (Pinus cembra) from Switzerland. To distinguish between neutral and adaptive SNP sets, we used four approaches (two gene diversity estimates, FST outlier test, and environmental association analysis) that search for signatures of selection. Second, we established ecological niche models for P. cembra in the study range and investigated how habitat suitability correlates with genetic diversity at neutral and adaptive loci. All estimates of neutral genetic diversity decreased with geographic peripherality, but were uncorrelated with habitat suitability. However, heterozygosity (He) at adaptive loci based on Tajima’s D declined significantly with increasingly suitable conditions. No other diversity estimates at adaptive loci were correlated with habitat suitability. Our findings suggest that populations at the edge of a species’ geographic distribution harbour limited neutral genetic diversity due to demographic properties. Moreover, we argue that populations from suitable habitats went through strong selection processes, are thus well adapted to local conditions, and therefore exhibit reduced genetic diversity at adaptive loci compared to populations at niche margins.