Abstract. Levels of diversity vary strikingly among different phylogenetic lineages of ants. Rapid radiations in early ant evolution have often proven difficul

Significance Archaeogenomic analysis of scarlet macaw bones demonstrates that the genetic diversity of these birds acquired by people in the southwestern United States (SW) between 900 and 1200 CE was exceedingly low. Only one mitochondrial DNA haplogroup (Haplo6) is present of the five historically known haplogroups in the lowland forests of Mexico and Central America. Phylogenetic analyses indicate the ancient macaw lineage in the SW shared genetic affinities with this wild lineage. These data support the hypothesis that a translocated breeding colony of scarlet macaws belonging to only one haplogroup existed some distance north of their endemic range, and SW peoples continuously acquired these birds from this unknown location for nearly 3 centuries, as no evidence currently exists for macaw breeding in SW. , Hundreds of scarlet macaw ( Ara macao cyanoptera ) skeletons have been recovered from archaeological contexts in the southwestern United States and northwestern Mexico (SW/NW). The location of these skeletons, >1,000 km outside their Neotropical endemic range, has suggested a far-reaching pre-Hispanic acquisition network. Clear evidence for scarlet macaw breeding within this network is only known from the settlement of Paquimé in NW dating between 1250 and 1450 CE. Although some scholars have speculated on the probable existence of earlier breeding centers in the SW/NW region, there has been no supporting evidence. In this study, we performed an ancient DNA analysis of scarlet macaws recovered from archaeological sites in Chaco Canyon and the contemporaneous Mimbres area of New Mexico. All samples were directly radiocarbon dated between 900 and 1200 CE. We reconstructed complete or near-complete mitochondrial genome sequences of 14 scarlet macaws from five different sites. We observed remarkably low genetic diversity in this sample, consistent with breeding of a small founder population translocated outside their natural range. Phylogeographic comparisons of our ancient DNA mitogenomes with mitochondrial sequences from macaws collected during the last 200 years from their endemic Neotropical range identified genetic affinity between the ancient macaws and a single rare haplogroup (Haplo6) observed only among wild macaws in Mexico and northern Guatemala. Our results suggest that people at an undiscovered pre-Hispanic settlement dating between 900 and 1200 CE managed a macaw breeding colony outside their endemic range and distributed these symbolically important birds through the SW.

Empirical population genetic studies generally rely on sampling subsets of the population(s) of interest and of the nuclear or organellar genome targeted, assuming each are representative of the whole. Violations of these assumptions may impact population-level parameter estimation and lead to spurious inferences. Here we used targeted capture to sequence the full mitochondrial genome from 123 individuals of the Galapagos giant tortoise endemic to Pinzón Island (Chelonoidis duncanensis) sampled at two time points pre- and post-bottleneck (circa 1906 and 2014) to explicitly assess differences in diversity estimates and demographic reconstructions based on subsets of the mitochondrial genome versus the full sequences, and to evaluate potential biases associated with diversity estimates and demographic reconstructions from post-bottlenecked samples alone. Haplotypic diversities were equal between the temporal samples based on the full mitochondrial genome, but single gene estimates suggested either decreases or increases in diversity depending upon the region. Demographic reconstructions based on the full sequence were more similar between the temporal samples than those based on the control region alone, or a subset of three regions, where the trends in population size changes shifted in magnitude and direction between the temporal samples. In all cases, the estimated coalescent point was more distant for the historical than contemporary sample. In summary, our results empirically demonstrate the influence of sampling bias when interpreting population genetic patterns and punctuate the need for careful consideration of potentially conflicting evolutionary signal across the mitochondrial genome.

The musk ox (Ovibos moschatus) is the only surviving member of a group of Pleistocene North American musk ox genera (Praeovibos, Ovibos, Bootherium, Euceratherium, and Soergelia) whose taxonomy is uncertain. The helmeted musk ox (Bootherium bombifrons) and the woodland musk ox (Symbos cavifrons) have been synonymised as male and female forms of a single Nearctic species found from Alaska, in the north, to Texas, in the south. However, this reclassification has not been tested using molecular data, despite the potential to use ancient DNA to examine these late Pleistocene taxa. In the present study, we sequenced mitochondrial genomes from seven subfossil musk ox specimens (originally identified as Bootherium and/or Symbos), allowing us to evaluate the identity of these muskoxen, explore their phylogeography, and estimate the timeline for their evolution. We also used nuclear genomic data to determine the sex of six of our seven samples. Ultimately, our molecular data support the synonymisation of the North American muskoxen Bootherium and Symbos.

We investigated a pantropical sub-family and genus of damselfishes, the sergeant-majors (Pomacentridae: Abudefdufinae: Abudefduf), to identify the tempo and mechanisms of speciation in the lineage. We examined sequence capture data from 500 loci and 20 species, with multiple individuals sampled from across the geographic ranges of widespread species. Utilizing a maximum likelihood framework, as well as a time-calibrated Bayesian phylogeny, the following key questions are addressed: What is the historical tempo of speciation? What are the relative contributions of vicariant, peripatric and parapatric speciation to sergeant-major diversity? How is speciation related to major variation in trophic ecology? The approximately 20 species of sergeant-majors fall into three main lineages. The ancestral condition appears to be benthivory, which is predominant in two lineages comprising six species. The remaining species of sergeant-majors, of which there are at least 15, fall within a clade composed entirely of planktivores. This clade is sister to a benthivore clade that included one species, Abudefduf notatus, in transition to planktivory. Most speciation of sergeant-majors, which appeared ∼24 million years ago, occurred in the last 10 million years. Present distributional patterns indicate vicariant speciation precipitated by the closure of land barriers between both sides of the Atlantic and the Pacific, and the emergence of land between the Indian and Pacific Oceans. Within this backdrop, frequent oscillations in sea level over the last 10 million years also appear to have generated conditions suitable for both peripatric and vicariant speciation, and most speciation within the genus appears linked to these changes in sea level. Diversification within the genus has been concentrated in planktivorous seargeant-majors rather than benthivores. The root cause is unclear, but does not appear to be related to differences in dispersal potential, which is greater in the planktivorous species, due to the ability of their post-larval juveniles to raft with floating debris. This elevated speciation rate in planktivores and their propensity to form local endemics may reflect relaxation of selective pressures (e.g., on crypticity) that limit speciation in benthivorous sergeant-majors. Finally, our data allow us to clarify relationships of geminate sergeant-major species, indicating that there are subdivisions within the Atlantic for both benthivore and planktivore geminate pairs that may have misled previous studies.

Rome initiated several campaigns to expand, conquer, and enslave local Italic populations following the establishment of the republic in 504 BCE. However, the cultural and biological changes resulting from Roman subjugation across Italy remain a topic of intense historical debate. Although important, historic and archaeological lines of evidence fail to track the impact of forced enslavement and enculturation at individual and broader genetic scales and, more generally, offer fewer clues regarding the potential affinities of Roman period Italians to European, Near Eastern, western Asian and North African populations at this time.

Premise of the Study Pinaceae have a rich but enigmatic early fossil record, much of which is represented by permineralized seed cones. Our incomplete knowledge of morphology and anatomy in living and extinct species poses an important barrier to understanding their phylogenetic relationships and timing of diversification. Methods We expanded a morphology matrix to 46 fossil and 31 extant Pinaceae species, mainly adding characters from stem and leaf anatomy and seed cones. Using parsimony and Bayesian inference, we compared phylogenetic relationships for extant taxa with and without fossils from the morphology matrix combined with an alignment of plastid gene sequences. Key Results Combined analysis of morphological and molecular characters resulted in a phylogeny of extant Pinaceae that was robust at all nodes except those relating to the interrelationships of Pinus, Picea, and Cathaya and the position of Cedrus. Simultaneous analysis of all fossil and extant species did not result in changes in the relationships among the extant species but did greatly reduce branch support. We found that the placement of most fossils was sensitive to the method of phylogenetic reconstruction when analyzing them singly with the extant species. Conclusions A robust phylogenetic hypothesis for the main lineages of Pinaceae is emerging. Most Early Cretaceous fossils are stem or crown lineages of Pinus, but close relationships also were found between fossils and several other extant genera. The phylogenetic position of fossils broadly supports the existence of extant genera in the Lower Cretaceous.

Noninvasive sampling is an important development in population genetic monitoring of wild animals. Particularly, the collection of environmental DNA (eDNA) which can be collected without needing to encounter the target animal facilitates the genetic analysis of endangered species. One method that has been applied to these sample types is target capture and enrichment which overcomes the issue of high proportions of exogenous (nonhost) DNA from these lower quality samples. We tested whether target capture of mitochondrial DNA from sampled feeding traces of the aye-­aye, an endangered lemur species would yield mitochondrial DNA sequences for population genetic monitoring. We sampled gnawed wood where aye-­ayes excavate wood-b­ oring insect larvae from trees. We designed RNA probes complementary to the aye-­aye’s mitochondrial genome and used these to isolate aye-­aye DNA from other nontarget DNA in these samples. We successfully retrieved six near-­complete mitochondrial genomes from two sites within the aye-­aye’s geographic range that had not been sampled previously. Our method demonstrates the application of next-­ generation molecular techniques to species of conservation concern. This method can likely be applied to alternative foraged remains to sample endangered species other than aye-­ayes.

Transcriptome-based exon capture methods provide an approach to recover several hundred markers from genomic DNA, allowing for robust phylogenetic estimation at deep timescales. We applied this method to a highly diverse group of venomous marine snails, Conoidea, for which published phylogenetic trees remain mostly unresolved for the deeper nodes. We targeted 850 protein coding genes (678,322 bp) in ca. 120 samples, spanning all (except one) known families of Conoidea and a broad selection of non-Conoidea neogastropods. The capture was successful for most samples, although capture efficiency decreased when DNA libraries were of insufficient quality and/or quantity (dried samples or low starting DNA concentration) and when targeting the most divergent lineages. An average of 75.4% of proteins was recovered, and the resulting tree, reconstructed using both supermatrix (IQ-tree) and supertree (Astral-II, combined with the Weighted Statistical Binning method) approaches, are almost fully supported. A reconstructed fossil-calibrated tree dates the origin of Conoidea to the Lower Cretaceous. We provide descriptions for two new families. The phylogeny revealed in this study provides a robust framework to reinterpret changes in Conoidea anatomy through time. Finally, we used the phylogeny to test the impact of the venom gland and radular type on diversification rates. Our analyses revealed that repeated losses of the venom gland had no effect on diversification rates, while families with a breadth of radula types showed increases in diversification rates, thus suggesting that trophic ecology may have an impact on the evolution of Conoidea.