Male is usually first cross listed.

here is more on the question.

Need to Understand HBG Genetics - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ords=childers&Search=true#Post474445

Sunfish (Centrarchid Fishes) genetics - Pond Boss Forum
https://forums.pondboss.com/ubbthre...ords=childers&Search=true#Post449213

From Childers (1967 data)

It is not known which sex is the heterogametic condition for the sex chromosomes of the four experimental species; however, Haldane (1922) formulated a rule which furnishes a clue: �When in the F1 offspring of a cross between two animal species or races, one sex is absent, rare, or sterile, that sex is always the heterozygous sex.� Using Haldane's rule, Krumholz (1950), in a study concerning BR F1 hybrids, pointed out that the males of both bluegills and red-ear sunfish are probably homozygametic for sex and the females heterozygametic. The application of Haldane's rule to all possible F1 hybrids produced from red-ear sunfish, bluegills, and green sunfish indicates that the female is the heterozygametic sex in these three species.

Last edited by ewest; 05/28/24 12:24 PM.