In a new study, researchers have found that that fighting fish or bettas moved or fought with each other in a synchronized manner. Genes in their brains were also examined, and the scientists discovered that the fishes' molecules seemed to be coordinated as well.
According to Alison Bell, a behavioral ecologist at the University of Illinois, Urbana-Champaign, the study depicts a perfect example of how social interactions can genuinely affect an individual.
The Betta splendens or Siamese fighting fish is a vibrantly colored small fish. In pet shops or at home, caretakers usually keep them in a separate tank or container due to their aggressive behavior. The fish are highly territorial and are known to get involved in fights that last more than an hour.
They usually bite, chase, and strike their foes. The fish would even lock jaws with its opponent in a duel. Although the mechanism in which the genes work remains to be unclear, the scientists consider the possibility of it occurring in humans as well.
Norihiro Okada, a molecular biologist from Kitasato University in Japan and colleagues, observed the behavior of the bettas in a duel. They captured footage of more than a dozen hours of fights between 17 pairs of fish.
In their findings, they found that the longer the fight, the more the fish integrated their behavior. Moreover, the researchers observed the precise timing of their striking, biting, and circling, and found similarities in the fish's actions. The findings of the study were published in the journal PLOS Genetics on June 17, 2020.
Choreographed Battles and Harmonized Moves
Moreover, the scientists observed that the fishes' duels lasted about 80 minutes, with seemingly "agreed upon" breaks between each strike. To them, it seemed like the fights were choreographed as they moved in harmony with each other.
They examined how bouts heighten every five to ten minutes when the fish locked onto each other's jaws and held on for as long as they could. Experts say it was a tactic to prevent breathing, which meant that they were testing each other on who could hold on longer.
After they break apart for a breather, a new cycle then begins. Furthermore, the researchers found that their coordinated actions happen at a molecular level as well.
After a 20-minute battle, five fish pairs were sacrificed, and the scientists then compared which chromosomes were activated during and after the fights. After 60 minutes, they repeated the procedure to another five pairs.
Interactive Brain Synchronization in Animals
Twenty minutes into the battle, the researchers found that "early intermediate genes," that switched on other genes, were engaged in each fish. Then at 60 minutes, they saw that hundreds more genes had harmonized expressions.
According to Hans Hofmann, an evolutionary social neuroscientist from the University of Texas in Austin, the team saw an exceptional degree of synchronization. Apparently, bettas aren't the only animals that scientists have observed to demonstrate synchronization in their actions.
In 2019, two teams reported in the journal Cell that communicating mammals synchronize brain activity. One paper studied bats flying around in a dark room and avoiding bumps, while the other tested supremacy in mice in a small arena. In both the findings of the studies, the longer the animals interacted, the more harmonized their brain activity became.
