Studies in Mass Physiology: Effect of Numbers upon the Oxygen Consumption and Locomotor Activity of Carassius auratus

ESEARCH ESEARCH on animal aggregations has shown that many physiological processes of animals are controlled or modified by the number of animals mutually participating in these processes. Allee (i93i and 1934) has comprehensively reviewed the work that has been done in this field. "Group effects" have been found for breeding, hibernation, estivation, growth, death-rate, resistance to toxic agents, and other processes. An effect of grouping on oxygen consumption has been demonstrated by Allee (1927), Schuett (i933 and 1934), and Bowen (1932). Schuett (1933), attempting to bridge the gap between the solitary fishes and those which exhibit highly integrated mechanisms of aggregation, reported that, in a given volume, the oxygen consumption of isolated goldfishes was significantly higher than if in a group of four. Stating that the unmodified Winkler technique he had used for determining oxygen tension was at fault, owing to nitrite contamination, Schuett (1934) repeated his experiments, using the permanganate modification of the Winkler method, and found no significant difference in oxygen consumption between goldfishes in isolation and in groups of four. Schuett (1934) and Escobar, Minahan, and Shaw (1936) pursued the analysis of the problem by determining the effect of grouping on the locomotor activity of goldfishes; they found a significantly higher rate of activity if the animals were isolated than if they were grouped. It has been the purpose of the present studies to repeat the analysis of this problem and to find the correlation, if any, between oxygen consumption and locomotor activity.