Medaka

[…] report oscillating patterns in the rate of genetic variation around the start sites of transcription in the medaka (Japanese killifish, Oryzias latipes ) genome.

Similar to the findings in medaka, fathead minnows treated with an intermediate concentration (10ng/L) of EE2 [18] in the ambient water at various timeranges throughout development did not result in sexreversal.^([sic])

Much of the research directed toward developing this technology has been done using model fish species such as medaka (Wakamatsu et al. 1994; Hong et al. 1996) and zebrafish (Sun et al. 1995; Ma et al. 2001; Kurita and Sakai 2004).