Food scarcity reduces reproductive organ mass even under long
photoperiods
The reduced body mass in high workload voles (Fig. 1G-J, Table S4)
confirms that a negative energy balance was induced by the
‘work-for-food’ protocol. This negative energy balance also caused a
15-47% reduction in testes mass (Fig. 1A,D; Table S4), a 0-50%
reduction in ovary mass (Fig. 1B,E; Table S4) and a 18-60% reduction in
uterus mass (Fig. 1C,F; Table S4). This effect appeared to be stronger
in tundra voles, and in female voles at low temperature.