UWEC CERCA 2025

Light is important for plants as an energy source for photosynthesis, as a measure of day/night and seasonal cycles, and as information about the surrounding environment. For this reason, plants have evolved a sophisticated set of pathways to detect and respond to light, which allows them to adjust their development in response to changing conditions. Red and far-red light are detected by photoreceptors called phytochromes. A genetic screen for Arabidopsis thaliana mutants altered in red-light response conducted by the Gingerich lab identified mutations in PHYB, the gene encoding the major phytochrome involved in red-light responses. We have found that one of these mutations, which is predicted to alter a single amino acid in the phyB protein, increases sensitivity to not only red-light but also blue. Furthermore, this increased blue sensitivity is exacerbated when the genes LRB1 and LRB2 (which encode proteins functioning in complexes that initiate red-induced degradation of the phytochromes) are disrupted. This suggests a previously unrecognized interaction between blue-light response and the red-light phytochrome response pathway. Characterization of the blue-light response of this mutant will be presented.

Biologists have long recognized the importance of two native rodent species – California ground squirrels and voles – as important ecosystem engineers and prey for a suite of predators in California ecosystems. However, in the twelfth year of studying California ground squirrels at Briones Regional Park, for the first time, we observed ground squirrels shifting their diets from primarily granivorous to actively consuming vole prey. In 2024, our team documented a total of 74 events involving the hunting, killing, and/or consuming of voles by ground squirrels. Here we explored associations between vole density and these events. First, we extracted iNaturalist data to quantify vole numbers. Vole sightings in 2024 were regionally high at our site and seven times greater than the 10-year average statewide. Second, we created heat maps to show that vole-squirrel events occurred mostly where vole and ground squirrel burrows were the closest at our site. Our findings reveal important associations between this unusual peak in vole numbers, close spatial proximity between voles and squirrels, and the emergence of novel carnivorous behaviors by squirrels. Thus, spatial overlap with a locally abundant prey in a boom year likely contributed to the emergence of unusual dietary shift by a granivorous mammal.

Natural selection is expected to favor foraging behaviors that allow animals to maximize energy gain in novel situations. Whereas many species are known to regularly hunt prey and eat meat, squirrels are largely considered to be flexible omnivores that consume mainly grasses and seeds. However, our team recently documented the widespread hunting of California voles (Microtus californicus) by California ground squirrels (Otospermophilus beecheyi). This novel behavior is unusual for the species and has not been studied before. Here, we analyze the behavior of ground squirrels during these predation events (N=22 events). We characterized the hunting sequence for the first time in the California ground squirrel. We define hunting as the active pursuit of prey. We know that some mammalian hunters (cursors) chase prey over distances whereas sit-and-wait predators use stealth to ambush prey. We found that California ground squirrels were successful in 59% of their hunts, typically chasing, pouncing, and then biting the neck or head of the vole before consuming it. Revealing these opportunistic patterns of behavior contributes to our broader understanding of mammalian hunting styles.

Anthropogenic changes are expected to influence behavior, stress physiology, and ultimately, lifetime fitness of animals. For social animals, external stressors imposed by human activities may interact with the social environment to either exacerbate or buffer stressors. In the context of human-induced rapid environmental change, long-term data on individually recognized social mammals has the potential to offer novel insights into the extent to which organisms can cope with social and ecological stressors. In this research, we established a new project focused on the behavioral ecology of North American beavers (Castor canadensis), a native ecosystem engineer, through monitoring using camera traps. We surveyed various public lands and identified several active family groups of beavers in West-Central Wisconsin. Our camera trap data indicate that the behavioral patterns and their interactions with other local fauna vary temporally within days and across seasons. Future research will focus on their social behaviors, including their monogamous lifestyles, dominance structures, communication systems, and movement ecology. The plethora of wildlife we monitored on our camera traps illustrates how beavers play a key role in shaping diverse and healthy wetland ecosystems. This research therefore has important implications for the management of wetlands and conservation of beaver populations in the region.

Mosquitoes are harmful, disease-carrying vectors that pose significant publichealth risks worldwide. Aedes aegypti, known for transmitting Zika Virus, Dengue, andyellow fever, poses a threat in various climates, while Aedes triseriatus—native toWisconsin—transmits the La Crosse virus.While much is known about adult mosquito behavior, less is understood about thesensory behaviors of mosquito larvae. To address this gap, our lab is investigating thechemosensory behaviors of Ae. aegypti and Ae. triseriatus larvae, particularly in relation toforaging. We have refined protocols using the InVision device, a high-resolution camerasystem designed for tracking aquatic invertebrates, to monitor and quantify the behavior ofmosquito larvae in response to chemical gradients emitted from a point source.With these methodologies, our research now focuses on sensory behaviorvariations across all mosquito larval and pupal stages. The mosquito life cycle consists offour instar (larval) stages, followed by a pupal stage before emerging into adulthood. Ourprevious findings suggest that L1 Ae. triseriatus and Ae. aegypti larvae do not rely onchemosensory modalities to locate food. Preliminary results indicate that foragingbehavior increases in L2-L4 instars, suggesting a developmental shift in foraging strategiesas larvae progress through these stages.

Dietary flexibility allows animals to respond adaptively to food pulses in the environment. Here we document the novel emergence of widespread hunting of California voles and carnivorous feeding behavior by California ground squirrels. Specifically, we aimed to investigate whether the age and sex of squirrels explained the extent to which they engaged in hunting, consumption, and/or competition over voles. This work is part of a long-term study at Briones Regional Park in California where squirrels of known ages and sexes are regularly live-trapped, marked, and released. In 2024, from June 10th to July 30th, we recorded all sightings of squirrels hunting, killing and/or consuming voles both opportunistically on trapping days and during formal behavioral observations. We found no significant difference in the age-sex composition of those individuals that engaged in any of these behaviors compared to those that did not hunt, consume, or compete over voles. Thus, juvenile and adult ground squirrels of both sexes depredate, consume, and/or compete over vole prey. Given that participation in hunting and consumption of voles was so widespread across members of the study population, future studies are required to understand whether these novel foraging behaviors were learned individually or spread socially throughout the study population.

Squirrels (Rodentia; Sciuridae) are a well-known and diverse group of rodents, including the charismatic ground-dwelling members of the Tribe Marmotini. In particular, the California ground squirrel (Otospermophilus beecheyi) is an emerging model system for the study of social and risk-sensitive behaviors in a rapidly changing world, as well as the physiology of resistance to snake venoms. To complement extensive natural history information for O. beecheyi, we provide a chromosome-scale genome to facilitate molecular studies focused on the genetic basis of ecologically important traits, population genetics, comparative genomics, and social evolution. The final scaffolded genome was 2.27 Gb contained in 9,960 contigs and placed into 28 1,383 scaffolds. The scaffold N50 was just over 125 Mb. We used the presence of 10,248 complete genes detected by BUSCO v5 specifically to compare broad patterns of chromosomal synteny between chromosomal scaffolds for O. beecheyi and two other sciurid rodents. The recovered pattern of synteny suggests several fusion and fission events for O. beecheyi to the other two species. This new information should advance our understanding of O. beecheyi, particularly concerning the study of social and risk-taking behaviors, and comparative studies of mammalian genomic biology and evolution.

Aging is a complex biological process influenced by a range of genetic, environmental, and physiological factors. Studying normal aging can help us better comprehend age related diseases and potentially lead to the identification of therapeutic targets. In this study, we use large transcriptomes collected from mouse and human brains (Tabula Muris and GTEx) to investigate genes, gene networks, and biological pathways that are selectively engaged at different biological ages through brain aging. We use a novel network biology platform called NetDecoder to determine which genes are highly utilized within brain specific biological networks; high utility genes are those that encode for important proteins that are crucial to a specific function, even if they are not differentially expressed. Our approach is unique because we can recover genes relating to the aging brain that are not differentially expressed, meaning they likely would not be pinpointed by other labs.

Cortisol is a hormone released in response to stress that is also vital to human development. Previous studies in lab have shown that cortisol exposure of zebrafish embryos resulted in hypolocomotion with increasing cortisol concentration. Cortisol acts through two receptors, the glucocorticoid receptor (GR) and mineralocorticoid receptor (MR). We tested if the activation of the GR receptor would produce similar effects on behavior to cortisol exposure. Dexamethasone is a synthetic gluccocorticoid that selectively binds to the GR. Zebrafish embryos were collected and treated with different concentrations of dexamethasone at 4-6 hours post-fertilization (hpf) in a 12-well plate. The resulting zebrafish were transferred at 5dpf to a 96-well plate, which was then measured in an 18-minute alternating light-dark assay to assess their locomotor behavior using a commercial motor tracking system. Two rounds of experiments, consisting of concentrations ranging from 100 to 1 uM showed differential relative behavioral phenotypes at different concentrations. These experiments inform our understanding of how corticosteroid receptors affect zebrafish behavior in embryonic development.

Glucocorticoids are steroid hormones vital to development and many physiological responses. The body’s primary glucocorticoid, cortisol, is released in response to stress and binds to two receptors: mineralocorticoid (MR) and glucocorticoid receptors (GR). Excess prenatal exposure to glucocorticoids has been linked to adverse effects on neurodevelopment. Previous work in the lab found that an increase in embryonic exposure to cortisol resulted in decreased swim behavior in zebrafish larvae 5 days post-fertilization (dpf). The goal of this study was to identify how selective MR exposure would affect behavior in larval zebrafish using deoxycorticosterone (DOC), a natural precursor to cortisol that binds to MR. Zebrafish embryos were treated with decreasing concentrations of DOC (1 µM, 0.3 µM, and 0.1 µM) at 4-6 hours post-fertilization (hpf) in a 12-well plate. Larvae were transferred at 5dpf to a 96-well plate and assayed using a commercial motor tracking system (Noldus DanioVision). Initial results indicate that the swim velocities for larvae exposed to 0.3 µM DOC were higher than control groups in the first dark cycle, but no other significant differences were observed. By investigating how DOC affects neurodevelopment in zebrafish, these results can inform future studies on the role of MR agonists in development.

This study investigated the diversity, growth, and abundance of macroalgal species on reefs surrounding San Salvador Island, The Bahamas, amid ongoing ecological change. Coral reef ecosystems are undergoing significant shifts due to climate change, habitat degradation, and the spread of invasive species. Understanding macroalgal communities during this transition is critical, as these organisms play a key role in reef structure and function. We conducted quadrat sampling and photo surveys across three reefs representing different levels of degradation. Algal diversity, including variations in growth forms and color patterns, was estimated from photographic data collected at over 50 quadrat locations. A subset of samples was analyzed to confirm species identifications and to assess photosynthetic capacity and growth strategies through quantitative measurements of biomass and chlorophyll content. Reefs around San Salvador Island support a diverse macroalgal community, including calcareous algae (Halimeda spp.), fleshy browns (Dictyota spp.), greens (Udotea spp.), and filamentous species. This study establishes a valuable baseline for understanding macroalgal responses to environmental change and contributes to ongoing reef conservation efforts.

Schistosomes are parasitic flatworms that cause schistosomiasis, a highly prevalent neglected tropical disease impacting over 250-million people worldwide. Life cycle progression through a snail intermediate host during their first larval stage, which are called miracidia, is required for worms to become infective to humans. The mechanism miracidia use to locate snails is not known. However, a secreted snail peptide known as P12 has been shown to elicit responses from miracidia that suggest it may serve as a cue for them in locating their snail hosts. The objective of this study was to investigate the role and structural requirements of P12 in Schistosoma mansoni miracidia host-seeking. P12 was cloned and sequenced from five snail species, revealing natural variation at 7 key residues. Quantitative methods were employed to characterize miracidia behavioral responses to snail cues and synthesized P12 variants. Preliminary findings suggest that stimulant gradients are required to elicit behavioral changes in miracidia. Infection experiments with live snails were carried out to determine if P12-rich solutions can disrupt these gradients and dysregulate miracidia sensation. Miracidia dysregulation control strategies are an under-researched approach to reducing the prevalence of schistosomiasis, but they could have especially significant impacts in endemic regions of the world.

The aim of this study is to understand how flatworms use their sensory capacities in their environments. Parasitic flatworms are a threat to human health globally. Understanding how these worms can find hosts to infect would help advance parasite control. This study focuses on Girardia dorotocephala, a species of free-living planaria we are developing as a flatworm model, uses chemoreceptors located in their auricles to sense their surroundings. While planaria are not parasites, they possess many of the same traits as parasites within the phylum. Both planaria and parasitic flatworms belong to the Platyhelminthes and have some of the same morphological features and molecular pathways. Because of the similarity between the two clades, we can use planaria as a model organism to better understand flatworm behavior. To initiate this project, we recorded and tracked planaria when placed in separate controlled environments. Experiment followed the planaria’s movements when placed in the presence or absence of food, or under different light conditions. We were also working on sequencing the genome to help identify genes potentially involved in sensation, setting up G. dorotocephala as a model flatworm for sensory experiments.

Schistosomiasis, a neglected tropical disease caused by three parasitic flatworm species,including Schistosoma mansoni, relies on freshwater snails as intermediate hosts. Interrupting theparasite’s ability to locate snails could provide a novel strategy for disease control. Praziquantelis the current treatment of choice for human infections, and it exerts its effect by targetingtransient receptor potential (TRP) channels on the parasite, leading to death of the worm. Despiteits effectiveness in eliminating adult parasites, treated individuals remain susceptible toreinfection.In this study, a drug screening approach was used to identify compounds targeting the transientTRP receptors in miracidia, a larval stage of the parasite. A custom 96-well acrylic device wasdesigned; worms were added to each well and treated with 10 µM of drug.The impact of eachcompound on miracidia behavior was assessed to identify potential drug candidates. Toaccurately monitor their responses, a high-resolution recording device was utilized. This systemenabled precise observation of miracidia motility and orientation, allowing identification ofcompounds that disrupt general movement or host-seeking behavior. Preliminary findingssuggest that TRP channel modulators play a role in altering miracidia navigation, offering apromising avenue for disrupting the parasite’s life cycle.

Schistosomiasis is a tropical disease caused by human-infective parasites of the genus Schistosoma. The larval stage, called miracidia, infects a snail intermediate host and matures into cercariae that are shed into water. Cercariae penetrate human skin and migrate to blood vessels connecting the intestines and liver. Here, mature parasites lay eggs that follow the flow of blood into the liver or against the flow into the intestines. Intestinal eggs will mature, be defecated into fresh water, and hatch to miracidia to continue the cycle of infection. In contrast, liver eggs have reached a dead end, but these are routinely harvested from rodent lab hosts for research use and maintenance of the life cycle. Previous evaluation of transcriptomic differences between the liver and intestine eggs revealed distinct functional differences, yet nothing is known about differences between miracidia derived from these eggs. We isolated distinct infected mice tissues and hatched miracidia. Using these miracidia, we performed RNA-seq analysis and found distinct transcriptomic clusters and differentially expressed genes between the samples. Future directions include experiments to test for differences between these miracidia in behavior and infection capacity. These findings will lead to deeper insights about relevant differences between miracidia from different tissues.

In lakes, mosses are distributed in deeper waters than any other form of plant life. Little is known about these plant communities, and this ongoing study by Dr. Lonzarich and his students is the most comprehensive of its kind. Prior work in this lab has explored the distribution and factors affecting the occurrence of mosses from 70 lakes in Wisconsin. The objectives of this study were to identify the mosses collected from these lakes using a DNA barcoding approach, which involves DNA extraction, PCR amplification of the LTS gene (barcoding gene), and sequencing using the Sanger method. An altermative method using the RBCL gene and next-generation sequencing is also being used. By identifying the species through online gene databases, the study intends to unravel the geographic distribution patterns of deep-water moss species in the state. The study builds on previous work that found difficulties in identifying moss species based on morphological characteristics due to their unique growth forms in deep-water habitats. Initial indications from morphological assessments suggest the presence of distinct geographic patterns in the distribution of deep-water mosses within Wisconsin's lakes.

Mobile applications like PictureThis use artificial intelligence to identify plant species, providing a convenient tool for users without botanical expertise. However, the accuracy of these applications remains uncertain, which is particularly important in ecological and conservation contexts, as misidentifications can have serious consequences. This study evaluated the reliability of PictureThis by comparing its identifications with genetic sequencing results from plant samples collected on the University of Wisconsin–Eau Claire campus. Ninety-four plant samples were analyzed, with sixty-five yielding positive genetic identifications. Of these, thirty-three (51%) matched the species-level identification provided by PictureThis, while twelve (18%) were confirmed at the genus level and five (8%) at the family level. The remaining fifteen (23%) showed no correspondence between genetic sequencing and app-based identifications. Discrepancies may stem from the app’s inability to identify certain plants, such as grasses, or its reliance on superficial similarities. Notably, genetic analysis confirmed that twelve plants identified by the app as non-native were actually native to Wisconsin, indicating an overestimation of non-native species. These findings highlight the limitations of AI-based plant identification apps and emphasize the need to supplement such tools with scientific validation when making ecological or conservation decisions.