Subterranean rodents spend most of the day inside underground tunnels. where there is little daily change in environmental variables. Our observations of tuco-tucos (Ctenomys aff. knighti) in a field enclosure indicated that these animals perceive the aboveground light-dark cycle by several bouts of light-exposure at irregular times during the light hours of the day. https://www.roneverhart.com/Hosa-SH-8X4-25-Stage-Box-Non-locking-8x4-25-p37478/