Cichlids change of sex
The snail-dwelling Metriaclima livingstonii. This is a small species that lives over the sand. When the fish is in danger, it escapes into an empty snailshell. Photo taken at Luwala Reef, Malawi.
© Cichlid Press / Ad Konings
© Cichlid Press / Ad Konings
What happens if the male dies?
“A male often has a harem – a set of females each living in its own shell. And what do you think will happen if the male dies?” asks cichlid specialist Ken McKaye.“Well, of course the dominant female of the harem changes sex. Research is still going on, but at the moment it seems that in this situation, the alpha female does turn into a male.”
Reproductive Biology 101
The fetuses of all vertebrates (that is, animals with backbones - mammals, birds, fish etc) have an elementary form of both male and female genitalia, and the capacity to develop one of either.
In most species, the sex of the fetus determines which genitalia develops, while the other gradually disappears. In several species however, including some fish, females grow female genitalia normally, while the elementary male genitalia maintains its potential for later development.
An external stimulus causes changes in the female's hormone levels, eliciting the male genitalia to begin maturing.
