Factors affecting the breeding of the field mouse (microtus agrestis). Part II.—Temperature and food

Abstract

Introduction .—In Part I (1931) we described experiments on the effects of light on reproduction in the field mouse. The conditions under which the control and experimental mice were kept was described in full. The control mice were kept for a year under summer conditions of temperature, food and daily period of exposure to light (15 hours), while the experimental mice had the same conditions of temperature and food, but light for only 9 hours daily. We call this the “ winter light ” experiment. The control mice bred throughout the year, but the winter-light mice scarcely at all. Concurrently with the winter light experiment, two other experiments were carried out against the same control. These were the winter temperature experiment and the winter food experiment, which are described in this paper.