What are Arenas and how do they work?

Arenas define the space in which flies can move. There are several types of existing behavioural arenas that can be used with the ethoscope and many more can be constructed depending on your specific needs. 3D printing is the method of choice for creating arenas. Most users will work with the regular arena (Panel A in the figure below). All our arenas are available on onshape.

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Very important. Arenas must have "targets". Targets are 4mm-diameter black disks that mark three of the four corners of the arena, at constant positions. They are recognised automatically by the ethoscope (see green crosses above) and are essential for the software to define regions of interest and adjust orientation. You will be able to record videos but not be able to start tracking experiments without targets! Printed arena provide three recess that can be used to position targets, in the form of small black paper circles. Print the PDF file below on A4 or letter paper, cut a square around the circle and glue it to each of the three slots.

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arena_targets.pdf

Commonly used arenas

The arenas below are the most commonly used ones. If you require access to a special model please get in touch and I’ll add it to the list. All the models can be freely accessed on onshape but they are all shared as view only. To modify them or export them you’ll first have to copy them to your own workspace, after creating your own, free, account. If you want to design your own arenas, you may want to start from these templates: HD template, full glass lid template, virgin template.

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Standard SD arena.

This is the most commonly used arena for sleep studies, also used in Geissmann et al Science Advances 2019 and many other studies. It is designed to work with the sleep deprivation module. It houses twenty 5mm silica glass tubes (VWR 201-1005) and it is designed so that every other slot will be slightly larger to comfortably accomodate tube rotations on the SD module. Model on onshape (here). A fixed version that is not compatible with tube rotations can be found here.

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SD Arena for 7mm silica glass tubes.

Conceptually similar to the classical arena above, but able to fit 7mm tubes, significantly larger than the ones we normally use for D.Melanogaster. The Arena hosts 16 tubes in total, 8 for each side. It is designed to still fit on sleep deprivators. Model available on onshape (here).

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2D Arena with removable wells.

This arena was used in Jones et al eLife 2023. It features 24 removable wells that can be filled with food and covered with regular 13mm coverslips, as used in microscopy (e.g. VWR 631-0148). Model available on ohshape (arena, wells). Also comes with a version of the well designed with curved wall profile as in Simon et al PLoS ONE 2010 (onshape).

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Arena for long 5mm tubes.

This fits 10 5mm tubes and it is designed to work with longer tubes. It was used in French et al Nature 2021 in which we used air pumps to deliver odour stimuli. The longer tube provides more room for the flies to move and therefore more robust choice when exposing flies to odours. Onshape model here.

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HD arena for courtship or fighting.

This arena is designed to be used for HD video recording. It features six fixed chambers designed for 1 to 1 encounters. The longitudinal slits can host two strips that serve as separating walls allowing to keep animals on their respective side until the experiment can start. The onshape model is here. Each of the wells also has an opening to insert animals using a blow tool and the opening can then be closed using this removable plug. Use 22mm square coverslips as lids for each chamber (e.g. VWR 631-0126).

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HD arena for 2D recording, square wells.

Each well can be filled directly with food or can be used to fit custom inserts. Also closing with 22mm square coverslips. Onshape model here or alternatively here for the version with open slits.

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non-HD arena with open wells.

Same as the one above but to be used with regular video or tracking. Features 12 wells. onshape model here.