Biology subjects

Strasser, F.

Publications and source records attributed to Strasser, F..

3 recordsLinked to original sources

bioRxiv2025

How to catch flies in the city (fast): Citizen Science on Drosophila ecology helps to raise awareness for biodiversity in urban environments

To efficiently mitigate biodiversity loss both robust ecological data and broader societal engagement are needed. Citizen science offers a pathway to address these dual challenges by combining data collection with public involvement. Here, we introduce the citizen science project Vienna City Fly, conducted at the Natural History Museum Vienna (NHMW), which used fruit flies (Drosophila) as a model organism group for urban biodiversity research and public engagement. Participants deployed standardized traps across Vienna, enabling systematic sampling and active participation in research, which resulted in hundreds of fly collections, thousands of sampled fly specimens and new insights into the biodiversity and ecology of the collected fly species, demonstrating the feasibility of large-scale ecological research through public collaboration. To assess motivational drivers and perceived impacts of participation, we conducted an online survey (N=59) using the validated psychometric MORFEN-CS scale. Survey results revealed that nature conservation values and the intention to contribute to biodiversity conservation emerged as the strongest drivers of engagement, complemented by sociopolitical responsibility and citizen science-based motivations. Reported outcomes include knowledge gain (61%), more positive attitude toward study organisms (50%), and increased awareness of biodiversity (30%). Satisfaction was very high, with 85% rating their experience at the top of the scale and all participants expressing willingness to join future citizen science projects. Recruitment occurred mainly via social networks, and the sample of participants was highly educated, indicating limits to inclusivity and reach. Our findings demonstrate that citizen science can contribute to robust ecological data collection while gaining knowledge and awareness. Natural history museums, as trusted institutions, play a key role in facilitating such initiatives. Overall, Drosophila research proves to be a suitable field for citizen science, combining accessibility with strong potential for advancing ecological and biodiversity research as well as public engagement in urban biodiversity research.

scientific communication and education↗

bioRxiv2025

Ecology and temporal dynamics of urban Drosophila species communities as potential indicators of biodiversity decline

Understanding the impact of ecological factors on biodiversity is central in the context of accelerating climate change and biodiversity loss. Urban areas, as landscapes under particularly strong anthropogenic influence, are undergoing rapid ecological change, yet the consequences for urban biodiversity and ecosystem functioning remain poorly understood. In this study, we focused on fruit flies of the genus Drosophila - a diverse group of dipterans with variable ecological niches and degrees of synanthropy - to investigate species composition and community ecology in the metropolitan area of Vienna, Austria. With the help of numerous citizen scientists, we have collected approximately 18,000 specimens through dense spatio-temporal sampling both indoors and outdoors of human dwellings. A total of 13 Drosophila species were identified, with communities dominated by widespread cosmopolitan synanthropic species. Among these, D. mercatorum and D. virilis represent novel records for Austria. Comparisons to a previous study from more than 30 years ago revealed that the species richness in Vienna was more than 50% lower than before and showed that formerly common species were potentially replaced by neobiots. We further assessed ecological niches by intersecting species abundance data with high-dimensional, high-resolution earth observation datasets, which revealed distinct ecological preferences among species. In particular, the neozoan D. mercatorum emerged as a highly synanthropic species, tightly confined to urban areas with high levels of imperviousness. In summary, our study underpins the versatility of the Drosophila system as indicators of biodiversity loss in a rapidly changing world.

ecology↗

bioRxiv2024

Optical tomography reconstructing 3D motion and structure of multiple-scattering samples under rotational actuation

Optical Diffraction Tomography (ODT) has emerged as a powerful tool for imaging biological cells in a non-invasive and label-free manner. However, conventional approaches using ODT by varying the illumination are plagued by the missing cone problem, which introduces ambiguity and deteriorates the axial resolution in the reconstruction. Although utilizing object rotation has the potential to yield isotropic resolution, experimental control or prior retrieval of the rotational parameters is challenging. In this work, we demonstrate ODT of multiple-scattering samples undergoing variable rotational motion, unlocking the potential for isotropic resolution in non-contact systems. We introduce a comprehensive reconstruction method to jointly retrieve both sample and rotational motion in 3D. An interferometric setup enables the recording of amplitude and phase data while the object is rotated in a non-contact manner around one or more chosen axes in an acoustofluidic device. We evaluate the tomographic reconstruction performance of the method for clusters of micro-beads and highlight its suitability for biomedical application beyond single cells, demonstrating high-resolution reconstruction of dense cancer spheroids containing more than 100 cells.

bioengineering↗