Sara B. Weinstein

Utah State University | USU

The longstanding interactions between mammals and their symbionts enable thousands of mammal species to consume herbivorous diets. The microbial communities in mammals degrade both plant fiber and toxins. Microbial toxin degradation has been repeatedly documented in domestic ruminants, but similar work in wild mammals is more limited due to constra...

Vertebrates rely on their gut microbiome for digestion, and changes to gut microbial communities can impact host health. Past work, primarily in model organisms, has revealed that endoparasites disrupt the gut microbiome. Here, using wild-caught white-throated woodrats (Neotoma albigula), we tested whether naturally acquired parasite infections are...

Fungi are often overlooked in microbiome research and, as a result, little is known about the mammalian mycobiome. Although frequently detected in vertebrate guts and known to contribute to digestion in some herbivores, whether these eukaryotes are a persistent part of the mammalian gut microbiome remains contentious. To address this question, we s...

DNA metabarcoding is widely used to determine wild animal diets, however whether this technique provides accurate, quantitative measurements is still under debate. To test our ability to accurately estimate abundance of dietary items using metabarcoding, we fed wild caught desert woodrats (Neotoma lepida) diets comprised of constant amounts of juni...

Little is known about the tolerances of mammalian herbivores to plant specialized metabolites across landscapes. We investigated the tolerances of two species of herbivorous woodrats, Neotoma lepida (desert woodrat) and Neotoma bryanti (Bryant's woodrat) to creosote bush Larrea tridentata , a widely distributed shrub with a highly toxic resin. Wood...

Fibricola and Neodiplostomum are diplostomid genera with extremely similar morphology that are currently separated based on their definitive hosts, i.e., Fibricola spp. are normally found in mammals, while Neodiplostomum spp. typically parasitize birds. Prior to our study, no DNA sequence data was available for any member of Fibricola. We generated...

Significance Understanding the factors that sculpt gut microbial communities in mammals is of great interest. Here, we studied a diverse clade of herbivorous rodents (woodrats, Neotoma ) with variable but well-characterized diets and habitats to quantify the relative contributions of host genetics, geography, and diet, alongside neutral processes,...

Pharyngostomoides, Alaria and Didelphodiplostomum are among genera of diplostomid digeneans known to parasitize mammalian definitive hosts. Despite numerous recent molecular phylogenetic studies of diplostomids, limited DNA sequence data is available from diplostomids parasitic in mammals. Herein, we provide the first 28S rDNA and cox1 mtDNA sequen...

The crested rat, Lophiomys imhausi, is the only mammal known to sequester plant toxins. Found in eastern Africa, this large rodent is thought to defend against predation by coating specialized hairs along its sides with cardenolide toxins from the poison arrow tree, Acokanthera schimperi. To better understand the ecology of this unusual poisonous m...

The COVID-19 pandemic has altered human behaviour in profound ways, prompting some to question whether the associated economic and social impacts might outweigh disease impacts. This fits into a burgeoning ecological paradigm suggesting that for both predator–prey and parasite–host interactions, non-consumptive effects (avoidance) can be orders of...

Infectious diseases have indelibly altered human history and, in doing so, have shaped the ecology and conservation of the natural world. Attempts to control diseases often result in adverse environmental impacts, including habitat degradation and unintended outcomes such as effects on non‐target species. However, in instances where the most effect...

A diversity of Borrelia burgdorferi sensu lato (Johnson, Schmid, Hyde, Steigerwalt & Brenner) (Spirochaetales: Spirochaetaceae) genomospecies, including the Lyme disease agent, Borrelia burgdorferi sensu stricto (s.s.), have been identified in the western United States. However, enzootic transmission of B. burgdorferi s.l. in small mammals and tick...

Ecotones can increase free‐living species richness, but little is known about how parasites respond to ecotones. Here we use parasite communities in raccoons (Procyon lotor) to test the hypothesis that parasite communities can be divided into core and satellite species, each with fundamentally different responses to ecotones. We used published para...

Local and global measurements of parasite prevalence and abundance are critical for understanding the dynamics that underlie the diversity, distribution, and evolution of infectious diseases. Here we present a dataset of gut helminths found in 1) raccoons throughout their range, based on primary literature from 1925‐ 2017 and 2) raccoons in Santa B...

Diagnosis of parasitic diseases that involve tissue stage larvae is challenging, and serology remains the most effective antemortem test for detecting these infections. Baylisascaris procyonis, the raccoon roundworm, is a zoonotic ascarid. Raccoons are the usual definitive host, and humans may be infected as accidental hosts. More than 150 species...

Predators often cause prey to adopt defensive strategies that reduce predation risk. The 'ecology of fear' examines these trait changes and their consequences. Similarly, parasites can cause hosts to adopt defensive strategies that reduce infection risk. However the ecological and evolutionary consequences of these behaviors (the 'ecology of disgus...

Parasite avoidance behavior affects ecology and evolution in ways similar to predator avoidance

Fear of predation alters prey behavior, which can indirectly alter entire landscapes. A parasite-induced ecology of fear might also exist if animals avoid parasite-contaminated resources when infection costs outweigh foraging benefits. To investigate whether animals avoid parasite contaminated sites, and if such avoidance balances disease costs and...

Baylisascaris procyonis (raccoon roundworm) infection is common in raccoons and can cause devastating pathology in other animals, including humans. Limited information is available on the frequency of asymptomatic human infection. We tested 150 adults from California, USA, for B. procyonis antibodies; 11 were seropositive, suggesting that subclinic...

The introduced black rat, Rattus rattus, occurs throughout the native range of the raccoon roundworm, Baylisascaris procyonis, and might incorporate into its life cycle if rats consume parasite eggs, acquire viable infections, and are eaten by raccoons. Although rats forage at raccoon latrines, their role in B. procyonis transmission remains unknow...

Biodiversity loss can alter disease transmission; however, the magnitude and direction of these effects vary widely across ecosystems, scales, and pathogens. Here we experimentally examine the effects of one of the most globally pervasive patterns of biodiversity decline, the selective loss of large wildlife, on infection probability, intensity and...

California has more reported human raccoon roundworm cases than any other state due to large and overlapping human and raccoon populations. Infection by this parasite, Baylisascaris procyonis, is relatively benign in raccoons but can cause severe pathology in other species. Disease risk is driven by environmental egg contamination which increases w...

Wild rodents such as Peromyscus spp. are intermediate hosts for the zoonotic ascarid Baylisascaris procyonis (raccoon roundworm) and previous studies indicate P. leucopus likely serves an important role in parasite ecology. Natural infections have been sporadically identified in a few Peromyscus species, but no data are available on differences in...

Nearly half of all animals may have a parasitic lifestyle, yet the number of transitions to parasitism and their potential for species diversification remain unresolved. Based on a comprehensive survey of the animal kingdom, we find that parasitism has independently evolved at least 223 times in just 15 phyla, with the majority of identified indepe...

Parasites can significantly impact animal populations by changing host behavior, reproduction and survival. Detecting and quantifying these impacts is critical for understanding disease dynamics and managing wild animal populations. However, for wild hosts infected with macroparasites, it is notoriously difficult to quantify the fatal parasite load...

Human actions can affect wildlife and their nematode parasites. Species introductions and human-facilitated range expansions can create new host-parasite interactions. Novel hosts can introduce parasites and have the potential to both amplify and dilute nematode transmission. Furthermore, humans can alter existing nematode dynamics by changing host...

Spinitectus gabata n. sp. (Spirurina: Cystidicolidae) from the gastrointestinal tract of an oarfish, Regalecus russelii, (Regalecidae), captured off the coast of Fukuoka Prefecture, Kyushu Island, Japan is the first nematode described from an oarfish. Diagnostic characters of the new species are: female length of 6.5-8.7 mm, well-developed submedia...

Abstract Examination of a small portion of the viscera of an oarfish recovered from Santa Catalina Island, southern California, revealed numerous tetraphyllidean tapeworm plerocercoids, Clistobothrium cf. montaukensis; 2 juvenile nematodes, Contracaecum sp.; and a fragment of an adult acanthocephalan, family Arhythmacanthidae. This suggests that th...

The pathogenic chytrid fungus Batrachochytrium dendrobatidis, typically associated with anuran amphibians, Is present In natural populations of the terrestrial salamander, Batrachoseps attenuatus, from California, USA, and four congeners from California and Oregon, USA. I demonstrate that the chytrid has been present in wild populations of B. atten...