Biology subjects

Keller, J. A.

Publications and source records attributed to Keller, J. A..

5 recordsLinked to original sources

bioRxiv2026

Mapping long-distance jump dispersal risk by leveraging transport infrastructure data and sampling bias correction: a case study with the invasive spotted lanternfly (Lycorma delicatula)

Long-distance jump dispersal accelerates invasive species spread. Analysis of past jumps can identify invasion pathways and point to locations at risk of future colonization, but spatial bias in survey records obscures patterns. To inform surveillance for the spreading invasive grape pest Lycorma delicatula (Hemiptera: Fulgoridae), we gathered 82,890 agency records of established invasive populations from the United States. We used a clustering algorithm to identify 207 jump dispersal sites, and we developed a bias-aware comparison dataset by filtering records to identify proactive search effort at locations not yet known to hold L. delicatula. We measured points' proximity to a co-produced list of 22 property types encompassing categories with high vehicle traffic, railroads, and related contexts that may transport L. delicatula. Bootstrapping analysis showed that proactive surveys were concentrated near hypothesized influential property types, confirming substantial sampling bias. With this bias accounted for, historical jump dispersal sites were closer than expected to 15 property types, particularly distribution centers, truck rentals, flea markets, and importers. We also compared the lengths of road and rail around these points, finding that jump sites were strongly associated with elevated rail density, whereas models showed limited support for roads as jump sites. Finally, we used the high-risk features to project risk of future jumps across the eastern U.S. using ensemble random forests. Predicted high-risk areas were northeast Illinois, southeast Michigan, and central Ohio. This framework is generalizable, allowing various pathways to be assessed and jump dispersal risk to be projected based on spatially biased surveillance data.

ecology↗

bioRxiv2026

Comparing pest survey methods through detection probability: seasonal and abundance-dependent detection of spotted lanternfly (Lycorma delicatula, Hemiptera: Fulgoridae)

BACKGROUND: Invasive species management demands accurate information on the distribution of targeted pests, but surveys have imperfect detection. Understanding the factors influencing detection probability can guide improved management planning. For the invasive spotted lanternfly (Lycorma delicatula), several sampling methods have been used. We evaluated three widely applied methods: 5-minute timed visual search, BugBarrier sticky band traps, and modified circle traps. These methods were used to quantify abundance in 5 x 20 m plots spanning the core to margins of five outlying satellite populations in Pennsylvania U.S.A. Methods were assessed every two weeks over the growing season for two years. RESULTS: Using a hierarchical Bayesian model, we found seasonal variation in all methods' detection probabilities, with timed visual search increasing in sensitivity over the course of the season and both tree-based traps showing a U-shaped pattern, with lowest detection probability around midseason. For timed visual search in plots used by ten L. delicatula individuals, the estimated probability of detecting at least one individual ranged from 10% to 53%. For tree-based traps, detection was higher on larger trees and on Ailanthus altissima, a preferred hostplant. For traps installed on A. altissima with diameter at breast height of 20 cm in a plot with the same L. delicatula density (N=10), estimated mean detection probability ranged from 33% to 99% for BugBarrier and from 28% to 84% for circle traps. CONCLUSION: Informed with estimated detection probabilities, managers can compare alternative survey methods and design strategic management plans that properly incorporate realistic survey sensitivity.

ecology↗

bioRxiv2025

Cortical control of innate behavior from subcortical demonstration

Motor control in mammals is traditionally viewed as a hierarchy of descending spinal-targeting pathways, with frontal cortex at the top 1-3. Many redundant muscle patterns can solve a given task, and this high dimensionality allows flexibility but poses a problem for efficient learning 4. Although a feasible solution invokes subcortical innate motor patterns, or primitives, to reduce the dimensionality of the control problem, how cortex learns to utilize such primitives remains an open question 5-7. To address this, we studied cortical and subcortical interactions as head-fixed mice learned contextual control of innate hindlimb extension behavior. Naive mice performed reactive extensions to turn off a cold air stimulus within seconds and, using predictive cues, learned to avoid the stimulus altogether in tens of trials. Optogenetic inhibition of large areas of rostral cortex completely prevented avoidance behavior, but did not impair hindlimb extensions in reaction to the cold air stimulus. Remarkably, mice covertly learned to avoid the cold stimulus even without any prior experience of successful, cortically-mediated avoidance. These findings support a dynamic, heterarchical model in which the dominant locus of control can change, on the order of seconds, between cortical and subcortical brain areas. We propose that cortex can leverage periods when subcortex predominates as demonstrations, to learn parameterized control of innate behavioral primitives.

neuroscience↗

bioRxiv2023

Differences in adult survival drive divergent demographic responses to a decade of field warming on the Tibetan Plateau

O_LIA central question in biodiversity conservation is whether species will maintain viable population dynamics under future climate change. Assessing species extinction risk under climate warming requires demographic studies integrating vital rate responses to long-term warming throughout species life cycle. However, studies of this nature are rare. C_LIO_LIHere, we examine the demographic responses of two co-occurring herbaceous plants, Elymus nutans Griseb. and Helictotrichon tibeticum (Roshev.) Holub, after a decade (2011-2020) of in situ active warming by 2{degrees}C in the grasslands of the Tibetan Plateau. We parameterise Integral Projection Models (IPMs) to project the population dynamics under ambient and long-term warming conditions, and examine the key vital rates responsible for any potential differences in population growth rates. C_LIO_LIWarming has contrasting effects on the two functionally similar co-occurring species: warming promotes the population growth rate of H. tibeticum, but intensifies the population decline of E. nutans. Our elasticity analyses show that survival is the most important vital rate for population viability in both species under both ambient and warmed conditions. Furthermore, our retrospective Life Table Response Experiment (LTRE) analysis reveals that the contrasting fates of the two species under warming mainly arise from the different responses of adult survival, which is significantly promoted in H. tibeticum but slightly reduced in E. nutans. Individual shrinkage occurred 1.6-fold more frequently under warming than ambient conditions for both species, and made considerable negative contributions to their population growth rates in warmed plots. However, such negative effects are offset in H. tibeticum (but not E. nutans) by the positive contribution to population growth rate of the associated increased survival. C_LIO_LISynthesis. Our study illustrates that the responses to climate warming may vary considerably between similar co-occurring species, and species with a demographically compensatory strategy may avoid population collapse. Additionally, caution is needed when generalizing findings among functionally similar species, and that conservation measures should be tailored at the species level. C_LI

ecology↗

bioRxiv2018

Brainstem control of urethral sphincter relaxation and scent marking behavior

Urination may occur either reflexively in response to a full bladder or deliberately irrespective of immediate need. Voluntary control is desired because it ensures that waste is expelled when consciously desired and socially appropriate1,2. Urine release requires two primary components: bladder pressure and urethral relaxation1-3. Although the bladder contracts during urination, its slow smooth muscle is not under direct voluntary control and its contraction alone is not sufficient for voiding. The decisive action of urination is at the urethral sphincter, where striated muscle permits fast control. This sphincter is normally constricted, but relaxes to enable urine flow. Barringtons nucleus (Bar, or pontine micturition center) in the brainstem is known to be essential for the switch from urine storage to elimination4-7, and a subset of Bar neurons expressing corticotropin releasing hormone (BarCRH) have recently been shown to promote bladder contraction8-10. However, Bar neurons that relax the urethral sphincter to enable urination behavior have not been identified. Here we describe novel brainstem neurons that control the external urethral sphincter. We find that scent marking behavior in male mice depends upon a subpopulation of spatially clustered Bar neurons that express high levels of estrogen receptor 1 (BarESR1). These neurons are glutamatergic, project to urinary nuclei in the spinal cord with a bias towards sphincter-inhibiting interneurons, and their activity correlates with natural urination. Optogenetic stimulation of BarESR1 neurons rapidly initiates sphincter bursting and efficient voiding in absence of sensory cues in anesthetized and behaving animals. Conversely, inhibiting the activity of these neurons prevents olfactory cues from promoting scent marking behavior. The identification of BarESR1 cells provides an expanded model for the supraspinal control of urination and its dysfunction.

neuroscience↗