Six sex changes per hour

1994/09/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Biologia

Ivan Ineitx, who works at the Museum of Natural History in Paris, has found a special type of reptile in Polynesia. It is produced without males. The eggs laid by geko females have two types of chromosomes. The female therefore lays eggs without germinating due to the presence of male chromosomes.

In the parthenogenesis of these reptiles will be obtained keys similar to those of the mother through the eggs, which when they grow will originate females without males. This will repeat the cycle over and over again.

Also special is the case of the small largemouth bass Serranus. These perches are hermaphrodites and can fulfill the function of male and female depending on the needs. When paired, the one who makes female paper has slower colors than the one who works as a male. After a few seconds of laying, the perch can change sex and re-match. Unpaired fish can lay eggs, change sex, and fertilize their eggs.

Serranus scriba is a perch that has both male and female gonads and that after a few hours can change sex six times. The perch Epinephelus striatus that inhabits around the Bahamas islands is even more peculiar. Some fish have gonads of both sexes, but can behave like males or females until arrival.

However, throughout evolution, half become large females and the other half become small males. Then, both of them definitely multiply by dominant sex. They have organs of both sexes, but only the dominant sex organs are active.

Thanks to this ability to change sex, the species presents a great variety and ease of survival.