@article{GrittnerBairdStoeckl2022,
  author    = {Grittner, Rebecca and Baird, Emily and St{\"o}ckl, Anna},
  title     = {Spatial tuning of translational optic flow responses in hawkmoths of varying body size},
  series = {Journal of Comparative Physiology A},
  volume    = {208},
  journal   = {Journal of Comparative Physiology A},
  number    = {2},
  issn      = {1432-1351},
  doi       = {10.1007/s00359-021-01530-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-266565},
  pages     = {279-296},
  year      = {2022},
  abstract  = {To safely navigate their environment, flying insects rely on visual cues, such as optic flow. Which cues insects can extract from their environment depends closely on the spatial and temporal response properties of their visual system. These in turn can vary between individuals that differ in body size. How optic flow-based flight control depends on the spatial structure of visual cues, and how this relationship scales with body size, has previously been investigated in insects with apposition compound eyes. Here, we characterised the visual flight control response limits and their relationship to body size in an insect with superposition compound eyes: the hummingbird hawkmoth Macroglossum stellatarum. We used the hawkmoths' centring response in a flight tunnel as a readout for their reception of translational optic flow stimuli of different spatial frequencies. We show that their responses cut off at different spatial frequencies when translational optic flow was presented on either one, or both tunnel walls. Combined with differences in flight speed, this suggests that their flight control was primarily limited by their temporal rather than spatial resolution. We also observed strong individual differences in flight performance, but no correlation between the spatial response cutoffs and body or eye size.},
  language  = {en}
}
@article{WalterDegenPfeifferetal.2021,
  author    = {Walter, Thomas and Degen, Jacqueline and Pfeiffer, Keram and St{\"o}ckl, Anna and Montenegro, Sergio and Degen, Tobias},
  title     = {A new innovative real-time tracking method for flying insects applicable under natural conditions},
  series = {BMC Zoology},
  volume    = {6},
  journal   = {BMC Zoology},
  doi       = {10.1186/s40850-021-00097-3},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-265716},
  year      = {2021},
  abstract  = {Background Sixty percent of all species are insects, yet despite global efforts to monitor animal movement patterns, insects are continuously underrepresented. This striking difference between species richness and the number of species monitored is not due to a lack of interest but rather to the lack of technical solutions. Often the accuracy and speed of established tracking methods is not high enough to record behavior and react to it experimentally in real-time, which applies in particular to small flying animals. Results Our new method of real-time tracking relates to frequencies of solar radiation which are almost completely absorbed by traveling through the atmosphere. For tracking, photoluminescent tags with a peak emission (1400 nm), which lays in such a region of strong absorption through the atmosphere, were attached to the animals. The photoluminescent properties of passivated lead sulphide quantum dots were responsible for the emission of light by the tags and provide a superb signal-to noise ratio. We developed prototype markers with a weight of 12.5 mg and a diameter of 5 mm. Furthermore, we developed a short wave infrared detection system which can record and determine the position of an animal in a heterogeneous environment with a delay smaller than 10 ms. With this method we were able to track tagged bumblebees as well as hawk moths in a flight arena that was placed outside on a natural meadow. Conclusion Our new method eliminates the necessity of a constant or predictable environment for many experimental setups. Furthermore, we postulate that the developed matrix-detector mounted to a multicopter will enable tracking of small flying insects, over medium range distances (>1000m) in the near future because: a) the matrix-detector equipped with an 70 mm interchangeable lens weighs less than 380 g, b) it evaluates the position of an animal in real-time and c) it can directly control and communicate with electronic devices.},
  language  = {en}
}