Zombie Ant Monitoring
One of the key user groups of the lab are researchers who want modified hardware. This project is exceptional in that a complete experimental setup was created from scratch. The objective were multiple set-ups without camera blind spots or shadows, getting there took a bit of thinking.
PhD candidate Emmeline van Roosmalen images the behaviour of ants after they have been infected by the fungus, Cordyceps. This family induces ‘height seeking behaviour’ in infected hosts. Rather than watch ants all day, Emmeline has a camera set-up to record them. The camera can detect the relatively dark ants against the light background. However, shadows would darken the background and prevents ants being measured. Ants also cannot be allowed to hide in crevices, cracks or blind spots. Lastly, the setup needed to be easily removable to clean and sterilize the boxes.
The first challenge was to produce a camera holder which would not generate shadows from external light sources. The solution was to use transparent acrylate sheet which could be laser cut to mount the camera. Emmeline bent the sides of the sheet at a 100 ̊ angle° (to match the viewing angle of the camera) and 3D printed sturdy mounts. The mounts clip onto the rim of the box, held down by finger tight bolts, and are glued to acrylate. Second, Emmeline designed a rim to hold and aim IR LEDs along the box edge. Special pieces of furniture for the ants included a nesting spot for the nights and a feeding station. Both were designed and printed by Emmeline to avoid shadows or crevices and ensure high contrast with the dark ants.
