Fig. 9.

Experimental design and results from testing injections. (A) Males that had never be socially dominant (N=60) were randomly divided into three groups of size-matched pairs. (B) In control animals, both members of the pair received vehicle injections. In experimental animals of one group (left), one member of the pair received l-methionine and the other received vehicle control; in the other group (right), one member of the pair received zebularine and the other received vehicle control. (C) Animals receiving l-methionine injections became socially dominant while those receiving zebularine did not. Modified from Lenkov et al. (2015).