Biology subjects

Moss, C. F.

Publications and source records attributed to Moss, C. F..

7 recordsLinked to original sources

bioRxiv2026

The functional diversification of somatosensory neuron repertoires across Mammalia

The striking diversity of mammalian body forms and surfaces, lifestyles, and habitats prompts the question of how each species' somatosensory neuron repertoire accommodates such diversity. The visual and olfactory systems diversify by gaining and losing sensor/receptor genes and corresponding sensory cell types. Using multiomic single-cell analysis of dorsal root ganglia neurons from thirteen different mammalian species and cross-species functional studies enabled by cell-type-specific enhancer viruses, we show that mammals instead assemble species-specific, functionally distinct somatosensory neuron repertoires from a conserved set of neuron types (orthotypes). Repertoire diversification takes multiple forms: orthotype abundance scales with variable bodily traits like hair follicle density, facilitating relevant behaviors; sensor/receptor expression is shuffled across species, such that orthotypes can detect different stimuli in different species; and orthotypes split into functionally distinct, species-specific subtypes (paratypes). Thus, unlike other sensory systems, the mammalian somatosensory system diversifies through multifarious changes to conserved orthotypes, enabling adaptation to diverse habitats, lifestyles, and body forms.

neuroscience↗

bioRxiv2026

Bats decouple sonar gaze from steering to resolve sensory conflict

When sensory modalities yield conflicting information, animals must rapidly reassess stimuli to select their actions. We induced auditory-visual conflict in free-flying echolocating Egyptian fruit bats, by fitting animals with prisms that shifted the perceived visual location of a landing perch while echoes returned from its veridical location. Bats that course-corrected within a single goal-directed flight did so by decoupling sonar gaze from steering, to enable rapid reweighting of visual and auditory cues. We designed artificial agents that used Bayesian inference to construct estimates of goal locations in their environment. When competing estimates directed active-sensing behaviors distinctly from steering, agents course-corrected more rapidly. Consistent with this idea, when bats were fit with prisms and earplugs that attenuated auditory localization cues, they were unable to course-correct. Removing prisms produced no systematic after-effects. Our framework suggests that instead of correcting their behavior after failure, animals could efficiently employ active sensing to resolve sensory conflict before failure occurs. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=178 SRC="FIGDIR/small/743555v1_ufig1.gif" ALT="Figure 1"> View larger version (41K): org.highwire.dtl.DTLVardef@e9374aorg.highwire.dtl.DTLVardef@12d03bforg.highwire.dtl.DTLVardef@5109d2org.highwire.dtl.DTLVardef@5bbb2e_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOCover figure.C_FLOATNO Bat wearing helmet with clear-glasses and tracking markers. Photograph (C) 2026 Nikita M. Finger / Moss Laboratory. C_FIG

neuroscience↗

bioRxiv2026

Bat eye movements resolve a long-standing question in gaze control

Eye movements enable visual information gathering and stabilize gaze via optokinetic (OKR) and vestibulo-ocular reflex (VOR) pathways.1 Echolocating bats, despite their rapid and agile flight maneuvers to land upside down and navigate 3D space, have long been thought not to move their eyes, an assumption originating from Wallss influential assertion over 80 years ago2 but never tested with empirical measurements. Here we present quantitative analysis of eye movements driven by visual and vestibular signals in Sebas short-tailed bat (Carollia perspicillata). Bats generated robust visually driven OKR with an oculomotor range of [~]{+/-}10{degrees}, and displayed strong otolith-mediated responses during off-vertical axis rotation. In contrast, they showed minimal semicircular canal-driven angular VOR (aVOR) for passive head rotations that elicit large, sustained responses in mice. Micro-CT reconstructions revealed that bats and mice have similar semicircular canal geometry, indicating that the weak aVOR does not reflect peripheral anatomical constraints. These findings provide the first empirical demonstration that bats make robust eye movements and exhibit strong visual and otolith-driven components of gaze stabilization. We propose that semicircular canal signals may be more strongly engaged during active flight and modulated by behavioral state-dependent tuning of vestibular pathways to support ecologically specialized behaviors.

physiology↗

bioRxiv2025

Sensorimotor dynamics in the superior colliculus of the echolocating bat

To successfully execute natural tasks, animals must continuously monitor and integrate dynamic sensory information to guide behavior. While this process - known as active sensing - is fundamental to goal-directed behavior, the mechanisms by which sensory information supports motor planning, particularly across different behavioral contexts, remains poorly understood. We investigated sensory and motor activity in the superior colliculus (SC) of echolocating bats, a powerful model system to study active sensing behaviors due to their reliance on self-generated sonar signals. We recorded multichannel SC activity while bats performed spatial navigation and target tracking behaviors. We hypothesized that changes in sensory signals (i.e., returning echoes) drive quantifiable adjustments in SC activity related to sonar call production, and that adaptive changes in SC sensorimotor processing are preserved across behavioral contexts. We examined pooled SC activity using a dimensionality reduction technique to isolate the largest changes in firing rates across multichannel SC recordings. We then examined the variation in SC activity from the time of echo arrival (sensory input) to call production (motor output). Our data show that increases in call rate are associated with shorter trajectory lengths in neural state space, reflecting reduced variability and increased efficiency in population activity. Strikingly, when bats cluster calls into sonar sound groups (SSGs, which are rapid bursts of calls to increase sensory sampling), SC activity is distinct from times when bats produce isolated calls. Notably, we find that successive SSGs lead to progressively shorter trajectory lengths, suggesting a refinement of sensorimotor processing across successive SSGs. Together, our findings demonstrate that sensorimotor population dynamics in the SC follow common principles across distinct behavioral tasks. These results support a fundamental role for the SC in adaptive sensing and highlight its contribution to flexible sensorimotor tranformations in natural behaviors.

neuroscience↗

bioRxiv2024

Why do bats fly into cave doors? Inattentional blindness in echolocating animals

Echolocating bats can navigate complex 3D environments by integrating prior knowledge of spatial layouts and real-time sensory cues. This study demonstrates that inattentional blindness to sensory information undermines successful navigation in Egyptian fruit bats, Rousettus aegyptiacus, a species that has access to vision and echolocation to traverse natural environments. Bats flew over repeated trials to a perch at a fixed location in the light, allowing them to navigate using both vision and echolocation. The experiment was then repeated in the dark to exclude the bats use of vision. The perch was subsequently displaced by either 15 or 30 cm in one of six different directions (up, down, left, right, front, back). Echolocation behavior was recorded using a 25-channel microphone array, while flight paths were tracked using 13 motion capture cameras. The directional aim of echolocation clicks served as a metric for the bats spatial attention to locations in their environment. In the light, bats modified their flight paths to successfully land on a perch that was moved 15 cm but surprisingly, often failed to land on it when displaced by 30 cm. In the dark, bats often failed to land on the perch after it was moved by only 15 cm. Landing failures suggest that learned spatial priors invoked inattentional blindness to changes in the environment, which interfered with successful navigation. In both the light and dark, when bats failed to land on the perch at its new location, they directed their attention toward the original perch position. Performance differences in the light and dark suggest that the bats attentional spotlight may be narrower when it relies on echolocation than vision. To our knowledge, these findings provide the first evidence of inattentional blindness in a flying echolocating animal, demonstrating that spatial priors can dominate sensory processing during navigation.

animal behavior and cognition↗

bioRxiv2024

Resistance to age-related hearing loss in the echolocating big brown bat (Eptesicus fuscus)

Hearing mediates many behaviors critical for survival in echolocating bats, including foraging and navigation. Most mammals are susceptible to progressive age-related hearing loss; however, the evolution of biosonar, which requires the ability to hear low-intensity echoes from outgoing sonar signals, may have selected against the development of hearing deficits in echolocating bats. Although many echolocating bats exhibit exceptional longevity and rely on acoustic behaviors for survival to old age, relatively little is known about the aging bat auditory system. In this study, we used DNA methylation to estimate the ages of wild-caught big brown bats (Eptesicus fuscus) and measured hearing sensitivity in young and aging bats using auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). We found no evidence for hearing deficits in aging bats, demonstrated by comparable thresholds and similar ABR wave and DPOAE amplitudes across age groups. We additionally found no significant histological evidence for cochlear aging, with similar hair cell counts, afferent, and efferent innervation patterns in young and aging bats. Here we demonstrate that big brown bats show minimal evidence for age-related loss of peripheral hearing sensitivity and therefore represent informative models for investigating mechanisms that may preserve hearing function over a long lifetime.

neuroscience↗

bioRxiv2023

Spatially clustered neurons encode vocalization categories in the bat midbrain

Rapid categorization of vocalizations enables adaptive behavior across species. While categorical perception is thought to arise in the neocortex, humans and other animals could benefit from functional organization of ethologically-relevant sounds at earlier stages in the auditory hierarchy. Here, we developed two-photon calcium imaging in the awake echolocating bat (Eptesicus fuscus) to study encoding of sound meaning in the Inferior Colliculus, which is as few as two synapses from the inner ear. Echolocating bats produce and interpret frequency sweep-based vocalizations for social communication and navigation. Auditory playback experiments demonstrated that individual neurons responded selectively to social or navigation calls, enabling robust population-level decoding across categories. Strikingly, category-selective neurons formed spatial clusters, independent of tonotopy within the IC. These findings support a revised view of categorical processing in which specified channels for ethologically-relevant sounds are spatially segregated early in the auditory hierarchy, enabling rapid subcortical organization of call meaning.

neuroscience↗