Research: Clownfish can change their species

The star of the movie "Finding Nemo" did not have to raise his son alone; Scientists have discovered that the exotic fish maintain a fixed social structure, and change their species, size and function according to need

Anyone who had time to watch the movie "Finding Nemo" must have been captivated by the undisputed hero of the movie, the colorful marlin fish, which belongs to the Shoshonon group, also known as the "clown fish".
Now some interesting details about the pet fish, which has become a hit in any self-respecting aquarium in the US, are becoming clear. Observations made by scientists show that fish live in a complex and "precise" social structure in nature. If one of the adult dominant fish disappears from the scene (is eaten, dies or simply moves to another group) the size, status and even the species of other fish in the group change rapidly, to maintain the status quo.

"If the female in the group dies, one of the males changes sex and becomes a female," said biologist Peter Boston, of Connell University. "The most undeveloped male suddenly becomes the biggest quadruped of all." The phenomenon of sex change, by the way, is also known among other species of fish.

The research on the exotic reef fish, named after their bold colors, appeared on 10/7/03 in the journal "NATURE".

Clownfish take the social structure of the group in which they live very seriously. In order to maintain the social structure, they will change their size with enormous speed and even their gender from male to female; This is according to a study carried out by a researcher from Cornell University in New York. According to the editor of the study, Dr. Peter Boston, the fact that in the case of the shoshannon, size does matter, is intended to preserve a social structure that helps them survive in harmony.

The shashanon is a relatively small fish, about 3.5 centimeters long. It is known as one of the colorful fish living in the coral reefs, and is characterized by a bright orange color, decorated with white and black. It got its name because of the symbiotic relationship it managed to develop with sea lilies. The lily hides inside its rose with poisonous arms, when it is pursued by its enemies and manages to develop a resistance to this poison. The researchers have not yet been able to discover the exact mechanism that allows it to escape the stings of the rose.

Dr. Boston traveled to New Guinea to study the Shoshones who live in the coral reefs. After studying about 100 Shoshonun groups he discovered that their social structure is strict and precise. Each group is composed of a male and a female shoshannon who are engaged in the work of reproduction, along with up to four other shoshannons who are not related to reproduction. The social rank within the group is closely related to the size of the rose. The female is the dominant one in the group, therefore she is the largest of them all. The male, which is engaged in reproduction, is ranked number 2 and is about 80% the size of the female. The next four shoshnons in line are also ranked and the size of each of them is about 80% of the fish that is higher in the social ranking.

Conflict prevention strategy

Dr. Boston examined how the fish in the group change their social role, when one of the members disappears. For this he removed the female from the group. In an article published in "Science" magazine, Boston describes how the remaining fish began to change, to adapt to the new situation. First, the male that was engaged in reproduction grew rapidly and reached the size of the female. Then he changed his gender from male to female. The largest of the four non-breeding shoshannons (number three in the previous hierarchy) also grew and took the male's place. Some of the remaining roses also grew accordingly.

According to Dr. Boston, the Shoshones' ability to control their size helps them avoid social friction in the group. Thus, for example, the Shoshones who are not busy with reproduction know that there is a chance that one day they will climb the social ladder. On the other hand, the Shoshnons that are related to reproduction have to constantly watch over their teammates so that they don't grow too large. "We found that if a fish reached a size that threatened the fish of a higher rank, it was immediately removed from the group," Boston said.

In an interview with "New Scientist" magazine, Boston described the evolutionary reason for the Shoshones' unusual mechanism: "It is designed to prevent social conflicts within the small group. The individuals spend a long time together (tens of years) and thus they can live in harmony."

Research: Clownfish can change their species

14/7/03

Anyone who had time to watch the movie "Finding Nemo" must have been captivated by the undisputed hero of the movie, the colorful marlin fish, which belongs to the Shoshonon group, also known as the "clown fish".
AdvertisementNow some interesting details about the pet fish, which has become a hit in any self-respecting aquarium in the US, are becoming clear. Observations made by scientists show that fish live in a complex and "precise" social structure in nature. If one of the adult dominant fish disappears from the scene (is eaten, dies or simply moves to another group) the size, status and even the species of other fish in the group change rapidly, to maintain the status quo.

"If the female in the group dies, one of the males changes sex and becomes a female," said biologist Peter Boston, of Connell University. "The most undeveloped male suddenly becomes the biggest quadruped of all." The phenomenon of sex change, by the way, is also known among other species of fish.

The research on the exotic reef fish, named after their bold colors, appeared on 10/7/03 in the journal "NATURE".

For news on Yahoo's news site