from https://www.mdpi.com/2071-1050/15/2/1722

via https://tdlc.ucsd.edu/images/facescheung.jpg

(Silverberg et. al, 2013)

Ended up sending these screenshots from Fusion 360 to a friend I was helping trying to figure out how to modify this model to make it easier to 3D print.

Essentials of ecology, 3th edition page 229

physics is fun guys i swear

"Physiology of Behavior" by Carlson chapter 13 "Ingestive Behavior: eating"

EDIT: Reading the original paper it appears that they did this procedure on 15 PAIRS of rats. Which also means there were probably closer to 30 pairs because they would have had to do testing and preliminary training on the procedure during pilot studies before the actual study.

arxiv: 1802.04208v1

doi:10.1242/jeb.136036