Hinny is easier to obtain when the lower chromosome count, the donkey, is in the male. Therefore breeding for hinnies is more hit-and-miss than breeding for mules." The male hinny or mule can and will mate, but the emission is not fertile. Male hinnies and mules are usually castrated to help control their behavior by eliminating their interest in females. Female hinnies and mules are not customarily spayed, and may or may not go through estrus. Female mules have been known, on rare occasions, to produce offspring when mated to a horse or donkey, although this is extremely uncommon. Since 1527,
The Female of the Species (poem) "Female of the Species". The title was again lifted in 2006 for Joanna Murray-Smith's satirical play "The Female of the Species". A 1946 novel by James Hadley Chase was titled "More Deadly Than The Male". Another novel, written by Mindy McGinnis, is titled “The Female of the Species.” In 1984, Off Centaur Publications released an audio tape cassette album titled "The Horse-Tamer's Daughter" featuring a song based on the poem, set to music by Leslie Fish and performed by Julia Ecklar. In 1998, the song was nominated for a Pegasus Award for "Best Adaptation" by a ballot of science fiction