Publications by authors named "Alexis P Sullivan"

Understanding the process of genetic adaptation in response to human-mediated ecological change will help elucidate the eco-evolutionary impacts of human activity. In the 1930s red imported fire ants (Solenopsis invicta) were accidently introduced to the Southeastern USA, where today they are both venomous predators and toxic prey to native eastern fence lizards (Sceloporus undulatus). Here, we investigate potential lizard adaptation to invasive fire ants by generating whole-genome sequences from 420 lizards across three populations: one with long exposure to fire ants, and two unexposed populations.

View Article and Find Full Text PDF
Article Synopsis
  • Intestinal microbiota plays a crucial role in various diseases, and understanding diet's impact on it is essential for developing targeted therapies.
  • A study analyzing meals and stool samples from 173 hospitalized patients found that higher caloric intake is linked to greater fecal microbiota diversity.
  • The research indicates that consuming sweets or sugars while on antibiotics may disrupt the microbiome, suggesting that reducing sugar intake during such treatment could help protect gut health.
View Article and Find Full Text PDF

Antibiotic-induced microbiome injury, defined as a reduction of ecological diversity and obligate anaerobe taxa, is associated with negative health outcomes in hospitalized patients, and healthy individuals who received antibiotics in the past are at higher risk for autoimmune diseases. No interventions are currently available that effectively target the microbial ecosystem in the gut to prevent this negative collateral damage of antibiotics. Here, we present the results from a single-center, randomized placebo-controlled trial involving 32 patients who received an oral, fermentation-derived postbiotic alongside oral antibiotic therapy for gastrointestinal (GI)-unrelated infections.

View Article and Find Full Text PDF
Article Synopsis
  • Gut microbiome dysbiosis is linked to COVID-19 severity, but a direct causal relationship has not been proven yet.
  • Research shows that SARS-CoV-2 infection leads to changes in gut bacteria in mice, which could compromise gut barrier function and increase infection risk.
  • Analysis of samples from 96 COVID-19 patients indicates that altered gut bacteria can enter the bloodstream, potentially causing severe secondary infections in these patients.
View Article and Find Full Text PDF
Article Synopsis
  • * Research using a mouse model shows that SARS-CoV-2 infection disrupts the gut microbiome and affects gut cell function, mirroring findings in human patients.
  • * The study found that hospitalized COVID-19 patients have an overgrowth of harmful bacteria, including antibiotic-resistant strains, which are associated with secondary infections that may originate from the gut.
View Article and Find Full Text PDF
Article Synopsis
  • A high-quality genomic reference assembly named SceUnd1.0 was created for the eastern fence lizard (Sceloporus undulatus), leveraging advanced sequencing technologies.
  • *The study explored chromosome evolution in lizards and snakes, revealing key changes like the fusion of chromosomes, and this genomic resource also supports improved references for 34 related Sceloporus species.
  • *Findings indicate that while the initial Supernova Assembly is effective for various analyses, incorporating additional data (HiC and PacBio) significantly improves structural genome insights, enhancing the utility for physiological and evolutionary research.*
View Article and Find Full Text PDF
Article Synopsis
  • The gut microbiome has been linked to the severity of COVID-19, but a direct causal relationship had not been clearly established before this study.
  • This research demonstrates that dysbiosis (imbalance) in the gut microbiome can lead to harmful bacteria entering the bloodstream during COVID-19, potentially causing serious infections.
  • Analysis of stool samples from COVID-19 patients showed significant microbiome imbalances, including an increase in harmful bacteria, which aligns with findings from a mouse model that confirms viral infection adversely affects gut health.
View Article and Find Full Text PDF

Although protocols exist for the recovery of ancient DNA from land snail and marine bivalve shells, marine conch shells have yet to be studied from a paleogenomic perspective. We first present reference assemblies for both a 623.7 Mbp nuclear genome and a 15.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

A genome-wide association study (GWAS) identifies regions of the genome that likely affect the variable state of a phenotype of interest. These regions can then be studied with population genetic methods to make inferences about the evolutionary history of the trait. There are increasing opportunities to use GWAS results-even from clinically motivated studies-for tests of classic anthropological hypotheses.

View Article and Find Full Text PDF

Due to our intensive subsistence and habitat-modification strategies-including broad-spectrum harvesting and predation, widespread landscape burning, settlement construction, and translocation of other species-humans have major roles as ecological actors who influence fundamental trophic interactions. Here we review how the long-term history of human-environment interaction has shaped the evolutionary biology of diverse non-human, non-domesticated species. Clear examples of anthropogenic effects on non-human morphological evolution have been documented in modern studies of substantial changes to body size or other major traits in terrestrial and aquatic vertebrates, invertebrates, and plants in response to selective human harvesting, urbanized habitats, and human-mediated translocation.

View Article and Find Full Text PDF

The Eurasian sympatry of Neandertals and anatomically modern humans - beginning at least 45,000 years ago and possibly lasting for more than 5000 years - has sparked immense anthropological interest into the factors that potentially contributed to Neandertal extinction. Among many different hypotheses, the "differential pathogen resistance" extinction model posits that Neandertals were disproportionately affected by exposure to novel infectious diseases that were transmitted during the period of spatiotemporal sympatry with modern humans. Comparisons of new archaic hominin paleogenome sequences with modern human genomes have confirmed a history of genetic admixture - and thus direct contact - between humans and Neandertals.

View Article and Find Full Text PDF

We have identified a fixed nonsynonymous sequence difference between humans (Val381; derived variant) and Neandertals (Ala381; ancestral variant) in the ligand-binding domain of the aryl hydrocarbon receptor (AHR) gene. In an exome sequence analysis of four Neandertal and Denisovan individuals compared with nine modern humans, there are only 90 total nucleotide sites genome-wide for which archaic hominins are fixed for the ancestral nonsynonymous variant and the modern humans are fixed for the derived variant. Of those sites, only 27, including Val381 in the AHR, also have no reported variability in the human dbSNP database, further suggesting that this highly conserved functional variant is a rare event.

View Article and Find Full Text PDF