We quantify locomotor behavior of freely walking and flying flies by videotaping them and extracting movements features using custom-written algorithms in Python. Flies walking on a 2D surface are filmed with a single camera and position as well as posture-related parameters such as body orientation and head angle are being extracted. For flying flies, 3 dimensions have to be taken into account. A calibrated camera system inspired by Straw et al. (2011) is used to obtain 3D position by triangulation. We combine these readouts with visual stimulation as well as (opto-)genetic circuit manipulation. With this approach, we hope to uncover some of the roles of visual neurons in a naturalistic context.
Straw AD, Branson K, Neumann TR, Dickinson MH (2011) Multi-camera real-time three-dimensional tracking of multiple flying animals. J R Soc Interface 8(56):395–409.