Biology subjects

van Giesen, L.

Publications and source records attributed to van Giesen, L..

4 recordsLinked to original sources

bioRxiv2026

Dispersal behavior in a cold-water coral is orchestrated via stage and species-specific physiology.

Corals form important ecosystems that serve as habitat for numerous marine species. Being sessile, adult corals are exposed to changing environments without the means to relocate. Species dispersal is therefore restricted to the motile larval lifestage. How do microscopic larvae achieve reliable dispersal and conquest of novel habitats under time pressure and unpredictable environmental conditions? Here we show an unexpected diversity of behaviors in the cold-water coral Lophelia pertusa. Anatomical and behavioral changes of coral planula promote a change from neutral, passive buoyancy in the dispersal phase, to active swimming and search behavior during competency. As lipids are metabolized and sensory abilities develop, the coral larvae drastically change their motility patterns. Comparative analysis with a poorly dispersing, lecithotrophic anthozoan larvae reveals that developmentally timed sensory integration is conserved between species, but the behavioral modes and sensory responses are adapted to their particular ecology.

developmental biology↗

bioRxiv2025

Developmentally timed sensory integration enables efficient larval dispersal

Animals integrate internal and external sensory information to adjust movement gait according to the physical constraints imposed by body-environment interactions. Efficient locomotion is especially important in small organisms where the motile phase is ontogenetically restricted. Motile larvae of otherwise sessile cnidarians must disperse and identify a suitable habitat in a restricted timeframe. Here we show that dispersal in Nematostella vectensis larvae is accomplished by a constant ciliary sensory-motor system that produces stimulus-induced movement. In contrast, neuro-muscular and sensory systems gradually increase in complexity during development, enabling movement-associated gait control through reafferent matching of external and internal information. Together with ciliary propulsion, the developmentally timed appearance of sensory and neuronal structures endows the animal with the ability to integrate information to shape swimming behavior and achieve dispersal in a timely manner, appropriate to the physical challenges of its specific ecological niche.

neuroscience↗

bioRxiv2025

Voltage-gated ion channel diversity underlies neuronal excitability and nervous system evolution

All nervous systems function via electrical excitability mediated by ion channels. However, channels and excitability are both ancient, preneuronal features that many cells use to rapidly adjust behavior. We systematically studied the evolutionary paths to neuronal excitability by characterizing the voltage-gated ion channel complements (VGL-chanomes) of 623 organisms, dissecting their expression patterns in 11 whole-body cell atlases and 3 entire nervous systems, and recording electrical properties of "primitive" neurons in the sea anemone. We find a disconnect between ion channel availability and organismal or nervous system complexity and find instead an association with lifestyle and behavior. Cell type restricted chanome expression predated the emergence of nervous systems in multicellular organisms. Multiple gene-family expansions and contractions independently specialized or diversified VGL-chanomes leading to a surprising convergent pattern: not the number of channels but their diversity and restrictive recruitment is a hallmark of neuronal complexity. These findings suggest that the evolution of highly complex nervous systems was not a stepwise progression of expanding complexity.

neuroscience↗

bioRxiv2020

A molecular filter for the cnidarian stinging response

All animals detect and integrate diverse environmental signals to mediate behavior. Cnidarians, including jellyfish and sea anemones, both detect and capture prey using stinging cells called nematocytes which fire a venom-covered barb via an unknown triggering mechanism. Here, we show that nematocytes from Nematostella vectensis use a specialized voltage-gated calcium channel (nCav) to distinguish salient sensory cues and control the explosive discharge response. Adaptations in nCav confer unusually-sensitive, voltage-dependent inactivation to inhibit responses to non-prey signals, such as mechanical water turbulence. Prey-derived chemosensory signals are synaptically transmitted to acutely relieve nCav inactivation, enabling mechanosensitive-triggered predatory attack. These findings reveal a molecular basis for the cnidarian stinging response and highlight general principles by which single proteins integrate diverse signals to elicit discrete animal behaviors.

physiology↗