gender transformation
Gender reassignment is a change in gender during individual development. There are a number of examples of sex reassignment in the animal kingdom. Still, she is an exception. Usually the gender is clearly defined, or double-sex individuals ( hermaphrodites ) arise .
Examples
- In the swordtail ( Xiphophorus helleri helleri ), a viviparous toothcarp , females gradually developed male sexual characteristics in very rare cases . It is said that in isolated cases these also produced offspring; However, this has not been scientifically proven. Most of the time, however, these are carriers of male characteristics who cannot function as males in the biological sense.
- Most perch-like coral fish can also be sexually changed.
- Females of river pearl mussels ( Margaritifera margaritifera ) undergo sex reassignment if too few males endanger the population.
During sex reassignment, physical transformations can also occur externally due to gender dimorphism .
Artificial sex reassignment
Some chemicals, such as certain halogenated hydrocarbons and steroids , can trigger artificial sex reassignment (as seen in frogs , for example ). Both the conversion of a male into a female and the reverse route were demonstrated.
Individual evidence
- ↑ World of Animals: Swordtail
- ↑ Joachim Großkopf: Sex differences in coral fish
- ↑ Ministry for the Environment and Nature Conservation NRW: Freshwater pearl mussel (Margaritifera margaritifera) ( Memento of the original from September 27, 2007 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ BUND : Hormonically active substances in water , September 2001 , order no. 45 078 ( Memento of March 11, 2004 in the Internet Archive )
