@phdthesis{Stiegler2023, author = {Stiegler, Jonas}, title = {Mobile link functions in unpredictable agricultural landscapes}, doi = {10.25932/publishup-62202}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-622023}, school = {Universit{\"a}t Potsdam}, pages = {155}, year = {2023}, abstract = {Animal movement is a crucial aspect of life, influencing ecological and evolutionary processes. It plays an important role in shaping biodiversity patterns, connecting habitats and ecosystems. Anthropogenic landscape changes, such as in agricultural environments, can impede the movement of animals by affecting their ability to locate resources during recurring movements within home ranges and, on a larger scale, disrupt migration or dispersal. Inevitably, these changes in movement behavior have far-reaching consequences on the mobile link functions provided by species inhabiting such extensively altered matrix areas. In this thesis, I investigate the movement characteristics and activity patterns of the European hare (Lepus europaeus), aiming to understand their significance as a pivotal species in fragmented agricultural landscapes. I reveal intriguing results that shed light on the importance of hares for seed dispersal, the influence of personality traits on behavior and space use, the sensitivity of hares to extreme weather conditions, and the impacts of GPS collaring on mammals' activity patterns and movement behavior. In Chapter I, I conducted a controlled feeding experiment to investigate the potential impact of hares on seed dispersal. By additionally utilizing GPS data of hares in two contrasting landscapes, I demonstrated that hares play a vital role, acting as effective mobile linkers for many plant species in small and isolated habitat patches. The analysis of seed intake and germination success revealed that distinct seed traits, such as density, surface area, and shape, profoundly affect hares' ability to disperse seeds through endozoochory. These findings highlight the interplay between hares and plant communities and thus provide valuable insights into seed dispersal mechanisms in fragmented landscapes. By employing standardized behavioral tests in Chapter II, I revealed consistent behavioral responses among captive hares while simultaneously examining the intricate connection between personality traits and spatial patterns within wild hare populations. This analysis provides insights into the ecological interactions and dynamics within hare populations in agricultural habitats. Examining the concept of animal personality, I established a link between personality traits and hare behavior. I showed that boldness, measured through standardized tests, influences individual exploration styles, with shy and bold hares exhibiting distinct space use patterns. In addition to providing valuable insights into the role of animal personality in heterogeneous environments, my research introduced a novel approach demonstrating the feasibility of remotely assessing personality types using animal-borne sensors without additional disturbance of the focal individual. While climate conditions severely impact the activity and, consequently, the fitness of wildlife species across the globe, in Chapter III, I uncovered the sensitivity of hares to temperature, humidity, and wind speed during their peak reproduction period. I found a strong response in activity to high temperatures above 25°C, with a particularly pronounced effect during temperature extremes of over 35°C. The non-linear relationship between temperature and activity was characterized by contrasting responses observed for day and night. These findings emphasize the vulnerability of hares to climate change and the potential consequences for their fitness and population dynamics with the ongoing rise of temperature. Since such insights can only be obtained through capturing and tagging free-ranging animals, I assessed potential impacts and the recovery process post-collar attachment in Chapter IV. For this purpose, I examined the daily distances moved and the temporal-associated activity of 1451 terrestrial mammals out of 42 species during their initial tracking period. The disturbance intensity and the speed of recovery varied across species, with herbivores, females, and individuals captured and collared in relatively secluded study areas experiencing more pronounced disturbances due to limited anthropogenic influences. Mobile linkers are essential for maintaining biodiversity as they influence the dynamics and resilience of ecosystems. Furthermore, their ability to move through fragmented landscapes makes them a key component for restoring disturbed sites. Individual movement decisions determine the scale of mobile links, and understanding variations in space use among individuals is crucial for interpreting their functions. Climate change poses further challenges, with wildlife species expected to adjust their behavior, especially in response to high-temperature extremes, and comprehending the anthropogenic influence on animal movements will remain paramount to effective land use planning and the development of successful conservation strategies. This thesis provides a comprehensive ecological understanding of hares in agricultural landscapes. My research findings underscore the importance of hares as mobile linkers, the influence of personality traits on behavior and spatial patterns, the vulnerability of hares to extreme weather conditions, and the immediate consequences of collar attachment on mammalian movements. Thus, I contribute valuable insights to wildlife conservation and management efforts, aiding in developing strategies to mitigate the impact of environmental changes on hare populations. Moreover, these findings enable the development of methodologies aimed at minimizing the impacts of collaring while also identifying potential biases in the data, thereby benefiting both animal welfare and the scientific integrity of localization studies.}, language = {en} } @misc{NuthmannVituEngbertetal.2015, author = {Nuthmann, Antje and Vitu, Fran{\c{c}}oise and Engbert, Ralf and Kliegl, Reinhold}, title = {No evidence for a saccadic range effect for visually guided and memory-guided saccades in simple saccade-targeting tasks}, series = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Humanwissenschaftliche Reihe}, number = {506}, issn = {1866-8364}, doi = {10.25932/publishup-41163}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-411639}, pages = {27}, year = {2015}, abstract = {Saccades to single targets in peripheral vision are typically characterized by an undershoot bias. Putting this bias to a test, Kapoula [1] used a paradigm in which observers were presented with two different sets of target eccentricities that partially overlapped each other. Her data were suggestive of a saccadic range effect (SRE): There was a tendency for saccades to overshoot close targets and undershoot far targets in a block, suggesting that there was a response bias towards the center of eccentricities in a given block. Our Experiment 1 was a close replication of the original study by Kapoula [1]. In addition, we tested whether the SRE is sensitive to top-down requirements associated with the task, and we also varied the target presentation duration. In Experiments 1 and 2, we expected to replicate the SRE for a visual discrimination task. The simple visual saccade-targeting task in Experiment 3, entailing minimal top-down influence, was expected to elicit a weaker SRE. Voluntary saccades to remembered target locations in Experiment 3 were expected to elicit the strongest SRE. Contrary to these predictions, we did not observe a SRE in any of the tasks. Our findings complement the results reported by Gillen et al. [2] who failed to find the effect in a saccade-targeting task with a very brief target presentation. Together, these results suggest that unlike arm movements, saccadic eye movements are not biased towards making saccades of a constant, optimal amplitude for the task.}, language = {en} } @article{FeldmannMaduarSanteretal.2016, author = {Feldmann, David and Maduar, Salim R. and Santer, Mark and Lomadze, Nino and Vinogradova, Olga I. and Santer, Svetlana}, title = {Manipulation of small particles at solid liquid interface}, series = {Scientific reports}, volume = {6}, journal = {Scientific reports}, publisher = {Nature Publishing Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/srep36443}, pages = {10}, year = {2016}, abstract = {The strong adhesion of sub-micron sized particles to surfaces is a nuisance, both for removing contaminating colloids from surfaces and for conscious manipulation of particles to create and test novel micro/nano-scale assemblies. The obvious idea of using detergents to ease these processes suffers from a lack of control: the action of any conventional surface-modifying agent is immediate and global. With photosensitive azobenzene containing surfactants we overcome these limitations. Such photo-soaps contain optical switches (azobenzene molecules), which upon illumination with light of appropriate wavelength undergo reversible trans-cis photo-isomerization resulting in a subsequent change of the physico-chemical molecular properties. In this work we show that when a spatial gradient in the composition of trans- and cis- isomers is created near a solid-liquid interface, a substantial hydrodynamic flow can be initiated, the spatial extent of which can be set, e.g., by the shape of a laser spot. We propose the concept of light induced diffusioosmosis driving the flow, which can remove, gather or pattern a particle assembly at a solid-liquid interface. In other words, in addition to providing a soap we implement selectivity: particles are mobilized and moved at the time of illumination, and only across the illuminated area.}, language = {en} } @misc{FeldmannMaduarSanteretal.2016, author = {Feldmann, David and Maduar, Salim R. and Santer, Mark and Lomadze, Nino and Vinogradova, Olga I. and Santer, Svetlana}, title = {Manipulation of small particles at solid liquid interface}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-100338}, pages = {10}, year = {2016}, abstract = {The strong adhesion of sub-micron sized particles to surfaces is a nuisance, both for removing contaminating colloids from surfaces and for conscious manipulation of particles to create and test novel micro/nano-scale assemblies. The obvious idea of using detergents to ease these processes suffers from a lack of control: the action of any conventional surface-modifying agent is immediate and global. With photosensitive azobenzene containing surfactants we overcome these limitations. Such photo-soaps contain optical switches (azobenzene molecules), which upon illumination with light of appropriate wavelength undergo reversible trans-cis photo-isomerization resulting in a subsequent change of the physico-chemical molecular properties. In this work we show that when a spatial gradient in the composition of trans- and cis- isomers is created near a solid-liquid interface, a substantial hydrodynamic flow can be initiated, the spatial extent of which can be set, e.g., by the shape of a laser spot. We propose the concept of light induced diffusioosmosis driving the flow, which can remove, gather or pattern a particle assembly at a solid-liquid interface. In other words, in addition to providing a soap we implement selectivity: particles are mobilized and moved at the time of illumination, and only across the illuminated area.}, language = {en} } @article{DumontNeumannNagyetal.2013, author = {Dumont, Hanna and Neumann, Marko and Nagy, Gabriel and Becker, Michael and Rose, Norman and Trautwein, Ulrich}, title = {Class composition Effects in non-academic lower secondary school tracks in the state of Baden-W{\"u}rttemberg}, series = {Psychologie in Erziehung und Unterricht : Zeitschrift f{\"u}r Forschung und Praxis}, volume = {60}, journal = {Psychologie in Erziehung und Unterricht : Zeitschrift f{\"u}r Forschung und Praxis}, number = {3}, publisher = {Reinhardt}, address = {M{\"u}nchen}, issn = {0342-183X}, doi = {10.2378/peu2013.art16d}, pages = {198 -- 213}, year = {2013}, abstract = {The study investigates the effects of classroom composition (average ability, achievement, and socio-economic background, proportion of immigrant students) on the development in mathematics achievement, and reading literacy from grade 5 to 6. The study draws on a sample of N=1892 students in vocational track schools (Hauptschule) and intermediate track schools (Realschule) in Baden-Wuerttemberg, Germany. After controlling for school type, and between-school differences in student intake characteristics, none of the compositional characteristics showed a statistically significant effect on achievement development. School track was associated with the development of reading literacy even after controlling for individual differences; however, this relationship lost its statistical significance after the composition of the student body was additionally taken into account.}, language = {de} } @article{DumontNeumannMaazetal.2013, author = {Dumont, Hanna and Neumann, Marko and Maaz, Kai and Trautwein, Ulrich}, title = {The effect of student body composition on academic achievement International and National Evidence}, series = {Psychologie in Erziehung und Unterricht : Zeitschrift f{\"u}r Forschung und Praxis}, volume = {60}, journal = {Psychologie in Erziehung und Unterricht : Zeitschrift f{\"u}r Forschung und Praxis}, number = {3}, publisher = {Reinhardt}, address = {M{\"u}nchen}, issn = {0342-183X}, doi = {10.2378/peu2013.art14d}, pages = {163 -- 183}, year = {2013}, abstract = {This paper reviews empirical evidence on the effect of the composition of a student body on academic achievement of students. After defining the term composition effect, methodological aspects regarding the study of composition effects are considered. International and national evidence for the composition of a student body with respect to students' abilities, social, and ethnic background is then presented. Whereas international studies find evidence for social, ethnic, and achievement composition variables, national studies reveal that mean achievement level of a school or class is the most important composition variable in Germany. However, this effect is confounded with school track and social composition, which itself exerts a small incremental effect. Ethnic composition, however, does not seem to play an important role. The paper closes with a presentation of the underlying processes of composition effects and a discussion on how the composition of a student body is considered in school governance practices.}, language = {de} } @misc{ChmielewskiDumontTrautwein2013, author = {Chmielewski, Anna K. and Dumont, Hanna and Trautwein, Ulrich}, title = {Tracking effects depend on tracking type}, series = {American educational research journal}, volume = {50}, journal = {American educational research journal}, number = {5}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-404052}, pages = {33}, year = {2013}, abstract = {The aim of the present study was to examine how different types of tracking— between-school streaming, within-school streaming, and course-by-course tracking—shape students' mathematics self-concept. This was done in an internationally comparative framework using data from the Programme for International Student Assessment (PISA). After controlling for individual and track mean achievement, results indicated that generally for students in course-by-course tracking, high-track students had higher mathematics self-concepts and low-track students had lower mathematics self-concepts. For students in between-school and within-school streaming, the reverse pattern was found. These findings suggest a solution to the ongoing debate about the effects of tracking on students' academic self-concept and suggest that the reference groups to which students compare themselves differ according to the type of tracking.}, language = {en} } @article{ChmielewskiDumontTrautwein2013, author = {Chmielewski, Anna K. and Dumont, Hanna and Trautwein, Ulrich}, title = {Tracking Effects Depend on Tracking Type}, series = {American Educational Research Journal}, volume = {50}, journal = {American Educational Research Journal}, number = {5}, publisher = {Sage}, address = {Thousand Oaks, Calif.}, issn = {0002-8312}, doi = {10.3102/0002831213489843}, pages = {926 -- 957}, year = {2013}, abstract = {The aim of the present study was to examine how different types of tracking— between-school streaming, within-school streaming, and course-by-course tracking—shape students' mathematics self-concept. This was done in an internationally comparative framework using data from the Programme for International Student Assessment (PISA). After controlling for individual and track mean achievement, results indicated that generally for students in course-by-course tracking, high-track students had higher mathematics self-concepts and low-track students had lower mathematics self-concepts. For students in between-school and within-school streaming, the reverse pat- tern was found. These findings suggest a solution to the ongoing debate about the effects of tracking on students' academic self-concept and suggest that the reference groups to which students compare themselves differ according to the type of tracking.}, language = {en} }