Belgium

Understanding how muscle contractions are coordinated to maintain stability and efficiency across varied locomotor tasks remains a key biomechanics challenge. Indirect evidence suggests that antagonist muscle co-activation stabilizes joints, but muscle force data remains limited, leaving the role of antagonist action in musculoskeletal energy transfer unresolved. We took a multi-scale approach, using Guinea fowl(Numida meleagris) to determine how an antagonist muscle pair generate and distribute energy during unsteady movement such as drop landings, slip–trip perturbations, and treadmill decelerations). We combined fascicle-scale (sonomicrometry), muscle-scale (tendon buckles, EMG) and musculoskeletal-scale (force plates, 3D motion capture) observations with center-of-mass analyses. Thereby, we captured a continuum of responses spanning from rapid perturbations to sustained decelerations. During drop landings, antagonist force and torque generation by tibialis anterior and lateral gastrocnemius facilitates controlled energy dissipation by adjusting limb stiffness to prevent joint collapse upon impact. Treadmill locomotion reveals antagonist torque overlaps at both toe-on and toe-off that manifest at low levels even during steady locomotion and increases during deceleration. Taken together, our direct, multi-scale measurements of antagonist muscle action indicate that co-contraction employs flexible mechanisms—adjusting timing and magnitude to perturbation severity—to foster robust, adaptable locomotion under diverse conditions. Thus, our study refreshes and refines traditional views of antagonist action and provides a framework for bio-inspired robotics and intervention strategies for efficient yet stable movement.

SEB Conference 2025

Feathered Balance: the roles of muscle antagonist action during locomotor perturbations.

antagonism

muscle

biomechanics

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technical paper

Thermal plasticity allows insects to adjust physiological traits in response to changing environmental temperatures. In temperate winter climates, low temperatures often coincide with shorter daylight periods. Photoperiod, the duration of darkness and daylight in a 24-hour cycle, affects many aspects of insect physiology, including seasonal plasticity and circadian rhythms. The yellow fever mosquito, Aedes aegypti, historically confined to tropical regions, is expanding its geographic range into poleward, temperate climates where it would experience varied temperature and photoperiod conditions. Ae. aegypti is capable of cold acclimation under a standard tropical photoperiod (12h:12h). Cold acclimation reduces injury and enables survival at otherwise lethal low temperatures. To test whether the ability to acclimate is tied to photoperiod, and when during the lifecycle photoperiod is important to Ae. aegypti thermal tolerance, we used an extreme photoperiod outside of their typical range (20h:4h), introduced at three different life stages; during egg development, during adult acclimation, and at the parental generation. A chill coma onset (CCO) assay was used to confirm the capacity for cold acclimation. Here, we present the first evidence of a photosensitive acclimation phenotype in this species. Extreme photoperiod significantly influenced CCO temperature, however, the magnitude of plasticity depends on when during development a light-cycle was introduced. To investigate the possible molecular mechanisms underlying this photosensitive acclimation phenotype, we are using qPCR to measure expression of known clock genes. This approach will help us gain a deeper understanding of the complex relationship between photoperiod cues and cold acclimation in Ae. aegypti.

Is thermal plasticity in Aedes aegypti sensitive to photoperiod?

Urban areas provide novel environments with a variety of new selective pressures, which makes them excellent systems to study contemporary evolution in response to anthropogenic environmental change. They are generally warmer than their surroundings (urban heat island effect), which, at high latitudes, can lead to decreased snow cover in cities during winter. Snow acts as an insulator, and thus snow cover loss might lead to increased temperature variation in urban ground temperatures. Insects often escape harsh winter conditions by diapausing under the snow cover, and urban insects might thus be exposed to increased thermal variation compared to rural insects. However, information on the effects of variable temperature on organism physiology and survival is scarce, especially during the winter season.
We performed a common garden laboratory study aiming to understand the effects of urbanisation and daily temperature variation on diapause energetics and termination timing inPieris napibutterflies. For this, we reared urban and rural populations at constant or variable temperature and measured diapause metabolic rate plasticity and diapause termination timing. We then combine these measurements with field microclimate temperature data to construct energy use models, which will help predict phenological patterns under field conditions. We expect that temperature variation will affect diapause metabolism and termination timing. However, if evolution in response to urbanisation has occurred, we expect urban butterflies to be less sensitive to temperature variation than urban ones.
This study will provide valuable insights on the capacity of ectotherms to evolve in response to variable thermal conditions

Effects of urbanisation and temperature variation on diapause in a temperate butterfly

The social environment during early life can play a pivotal role in the development of the behavioural phenotype. As colonial breeding species experience significant variation in their social environment, with central parts typically showing higher concentrations of territories then peripheral parts, the parental territory choice could have consequences for the their offspring’s behavioural phenotype. To accommodate these effects parents might pre-adjust their offspring via maternal effects to match the post-hatching conditions.
We tested in lesser black-backed gulls whether the fact that chicks in dense breeding areas are exposed to more aggression impinges on their movement activity and exploratory behaviour. We cross-fostered full clutches between and within high- and low-density parts of the colony, used ultra-wideband tags to track free-ranging chicks, and collected data on the chicks’ exploratory phenotype in an open field test. Post-fledging exploratory movements of juveniles were studied over a 20-day period using GPS tracking.
We found that movement activity and exploratory behaviour measured different aspect of the chicks phenotype, but both were affected by the social environment. Chicks reared in denser areas had a lower movement activity, and chicks in high breeding densities were less explorative, which was reinforced by pre-natal maternal effects. When studying exploratory aspects of foraging post-fledging, only habitat preferences were weakly linked to the chicks’ exploratory phenotype pre-fledging. We conclude that offspring adjust their behaviour to their early social environment, facilitated by maternal effects, but the (as yet limited) juvenile data suggest that these effects are not lasting.

Growing up in a crowd - the early life of lesser black-backed gull chicks

Reactive oxygen species  function as key signals in plant adaptation to environmental stresses like drought. Roots respond to transient water unavailability by temporarily ceasing branching through the acclimative response xerobranching. In this study, we report how a xerobranching stimulus triggers rapid changes of ROS levels  in root nuclei, triggering redox-dependent multimerization of the auxin repressor protein IAA3. Mutations in specific cysteine residues of IAA3 disrupt redox-mediated multimerization and interaction with co-repressor TPL, thereby attenuating IAA3 mediated  target gene repression. Other AUX/IAA proteins also vary in their redox mediated multimerization, revealing a regulatory mechanism that connects dynamic changes in cellular redox status to auxin signalling.  Our study reveals how ROS, auxin and water availability intersect and  shape root adaptive responses, thereby maintaining  phenotypic plasticity in plants.

Redox regulated Aux/IAA multimerization modulates auxin responses

There is increasing evidence in STEM education that creativity and innovation occur in spaces at the edge and in-between. This talk presents research, conducted at a STEMMB-focused university, that employed a mixed-methods approach to explore student transitions between formal and informal learning spaces. Applying an ecological lens helped to reveal tensions between timetabled and non-timetabled spaces which students navigate as part of their learning experience. These insights informed the redesign of campus transitional spaces across multiple departments to foster more serendipitous learning experiences and collaboration within the university community. The research highlights the untapped potential of in-between transitional spaces for creativity, innovation, and learning—an area that warrants further exploration.

Beyond the classroom: rethinking the ecology of learning spaces in STEM education 

The modern workplace requires teamwork bridging distances, time-zones and cultures using virtual collaboration platforms. As such teamwork is a key employability skill for our graduates, and yet we rarely explicitly teach team skills or how to navigate and collaborate in a virtual environment. Here we demonstrate that integrating in-person (synchronous) and online (synchronous and asynchronous) learning environments can prove an extremely resilient teaching method that allowed continuity during the pandemic, while providing students with these essential skills. But this isn’t just a story about using collaborative software – this is also a student journey into the creative side of science communication. The assessment (which we all know is what matters to students!) is a semester long documentary video team assignment supported by regular compulsory team training sessions and using the Microsoft Teams online collaboration platform. Students interview researchers outside the University of Nottingham (our home university) and create animations, film footage and determine stock footage that is legal to use. I would love to share this journey with you, from both my instructor view and the student perspective and introduce new directions we are exploring with virtual reality.

Virtual Teamwork and Creativity: A Journey in Science Communication

Since the late 2010s, artificial intelligence (AI), including machine learning and deep learning, has transformed life science research by enhancing the computational analysis of biological processes, natural product discovery, and ecosystem understanding. The surge in high-throughput omics data has made AI-based analyses essential for deciphering complex datasets, with phenotyping facilities becoming crucial in advancing plant sciences.
This presentation focuses on plant metabolism and the role of omics-based predictive analytics in systems biology. By using plant metabolomes as an integrative system, machine learning tools have been employed to address critical areas such as plant resilience to extreme environments and plant-soil interactions. These AI-driven approaches have provided deeper insights into the complex biological systems governing plant life. For instance, metabolic profiles of 24 plant species from the Atacama Desert could predict plant growth elevation with 79% accuracy using only 39 compounds, revealing a shared metabolic toolkit for coping with extreme conditions like freezing temperatures, water deficit, and intense solar radiation.
The presentation also discusses future challenges and opportunities in using AI in plant sciences, offering strategies to advance AI-based predictions of complex plant traits. It highlights AI's potential to revolutionise our understanding of plant biology and its applications in agriculture and environmental conservation.

AI-based metabolome predictions to study complex plant traits

Avena fatua (common wild oat) is a weed affecting the yield of cereals, such as wheat and barley. Its combination of rapid growth and tall statue (high competitive ability) with abundant seed production (high fecundity) make it particularly problematic. Based on the hypothesis that inflorescence photosynthesis contributes to carbon capture for seed production, we explored photosynthetic gene expression in inflorescence organs and the impact of source-sink manipulation on seed formation. Initial analysis of mRNA-Seq comparing inflorescence organs (glume, lemma, palea and awn) to leaves shows higher expression of genes involved in fatty acids synthesis (lipoxygenase), sucrose and secondary metabolism (carbohydrate accumulation and distribution and lignin and flavonoids synthesis) but lower expression of genes related to RuBisCO activity and photochemical efficiency. Defoliation, shading of the inflorescence and de-awning of plants reduced total seed weight by 13, 32 and 38 %, respectively. This indicates that inflorescences, and particularly the awn, contribute more to seed carbon gain than the leaves. Additionally, inflorescence shading and de-awning resulted in a significant delay in stem senescence and higher leaf photosynthesis, suggesting that leaf and stem senescence is determined by source-sink interactions. Extended photosynthetic lifespan of the leaves could increase stem reserves to sustain longer seed filling when photoassimilates in the leaves and stems are depleted in the absence of inflorescence photosynthesis. Altogether, A. fatua exhibits remarkable inflorescence photosynthesis, contributing to seed carbon assimilation, thus supporting high fecundity.

The role of inflorescence photosynthesis in the high fecundity of an agricultural weed, Avena fatua

Far-red light is abundant in natural sunlight, particularly in shaded leaves within plant canopies. Although traditionally excluded from photosynthetically active radiation (PAR), recent studies suggest that far-red can enhance leaf photosynthesis (An ) and reduce mesophyll conductance (gm ) at low light intensities. This triggered an interesting debate: should PAR be redefined?
Previous research, however, was conducted on plants grown in artificial ‘white’ lighting in climate chambers, with spectral conditions differing significantly from natural sunlight. Furthermore, these studies used unrealistic low far-red fractions in control treatments, raising questions about their applicability to field conditions.
To address this, we grew tomato plants under a simulated sunlight spectrum (400-750 nm) at 300 mmol PAR m-2 s-1 . We measured An  and gm  in 25-days-old leaves under normal, increased, and decreased (field-unrealistic) far-red fractions in sunlight PAR. We used a LI6800 and LI7800 Stable Isotope Analyzer system to monitor An  and gm  over 3-4 diurnal cycles, measuring at 5 min⁻¹, under constant and sinusoidal diurnal intensity patterns.
Our results show that increasing far-red—mimicking the shift from unshaded to shaded leaves in the field—did not significantly affect An  or gm . However, removing far-red, comparable to previous studies, reduced An  and gm  throughout light periods regardless of light intensity variation.
These findings suggest that while far-red plays a role in photosynthesis, its effect in realistic field conditions may be less pronounced than previously thought. However, its role can be significant in protected cultivations, where low fractions of far-red frequently occur.

Bridging with Care: Does Far-Red Light Influence Photosynthesis in Field Conditions?

Aquatic ectotherms are highly vulnerable to climate change, prompting extensive research into the factors that determine their upper thermal limits. A common method to assess thermal tolerance is the critical thermal maximum (CTmax), defined as the temperature at which organisms reach a critical non-lethal endpoint marked by a reversible loss of equilibrium. The physiological mechanisms behind CTmax are still being debated, with a particular focus on mitochondrial dysfunction. Indeed, mitochondria are essential for aerobic metabolism by producing ATP coupled to oxygen consumption through oxidative phosphorylation, which has a highly variable activity and is influenced by temperature. This study aimed to evaluate whether mitochondrial phosphorylation and coupling efficiency are impaired at CTmax temperature in a little-known fish species, the spirlin (Alburnoides bipunctatus), whose long-term persistence in large temperate rivers is questioned under climate change. Wild spirlins were acclimatized at 20°C for two months. Once their CTmax was determined (33.85°C ± 0.12°C), mitochondrial respiration rates and ATP/O ratio (mitochondrial efficiency) were assessed at 20°C and 34°C. Our findings show that mitochondrial complex I respiration is more sensitive to temperature than complex II respiration, and that the ATP/O ratio decreases at CTmax temperature, indicating an increased cost of mitochondrial ATP synthesis at this higher temperature. This observation suggests an increased energy constraint on cellular performance, which may play a role in organismal thermal tolerance. Yet, other organs, such as the heart and brain, are more sensitive to temperature than muscle, underlining the need for further research into mitochondrial efficiency in these organs.

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Is thermal plasticity in Aedes aegypti sensitive to photoperiod?

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