The Intelligence of Betta Fish

Contrary to popular belief, Siamese fighting fish are fairly intelligent. Research indicates they have complex behaviors, social interactions, and even individualized personalities. Males engage in carefully coordinated combat, dance-like courtship, and the building of “bubble nests”, which they fiercely protect; all this indicates a fairly well developed nervous system. Bettas are even capable of associative learning, meaning they develop and adopt certain responses to new stimuli (think of Pavlov’s famous experiment with dogs, where they learned to associate a bell ring with food).

Having had bettas for over fifteen years—including around 36 at the moment (blame the pandemic!)—I can vouch for this by personal experience. Our bettas are inquisitive, alert, and generally perceptive of their surroundings, watching and exploring anything new that comes their way. They also have varied personalities: Some are nearly always aggressive, tending to flare at us when we walk by; others are more shy and reclusive. They even have distinct tastes in food (which has prompted me to get several different brands and types).

Image may contain: plant
Our beautiful betta Dream, a “dumbo” or “elephant ear” type.

Now, aside from this being anecdotal, I know we humans tend to anthropomorphize animals, especially our pets, attributing human traits, behaviors, and intelligence to their natural behaviors. But there is quite a bit of scientific research backing my impressions (and perhaps those of fellow betta fish keepers).

In fact, Siamese fighting fish are frequently utilized in physiology and psychology studies due to their complex biology; many scientists in these fields consider them “prime models” in understanding how hormones and other hormones affect behavior.

For example, one study found that bettas were affected by antidepressants, specifically fluoxetine, which relies on serotonin transporter pathways to regulate behaviors; in this case, the bettas saw a reduction in their characteristic aggression, which indicates that have a comparable neurological framework. (In fact, bettas can be bored, depressed, and happy; moving them to a bigger tank or placing new decorations will elicit a positive response, with each specific betta having its own preference.)

A more recent study showed that bettas are able to synchronize their behavior during fights—something that has been observed among mammal as well! The longer they fought, the more they could precisely time their strikes and bites, to an extent that surprised the researchers. The study also determined that fights are highly choreographed, with seemingly “agreed on” breaks between each move. Bouts escalated every five to ten minutes, when fish locked onto each other’s jaws to prevent breathing—and thus test who can hold out the longest. The bettas then break apart to catch their breath, and the cycle begins anew—not unlike a boxing match!

Even more surprising, the team found that this synchronicity went down to the molecular level: Certain genes of the combatants were “turned on”, and while it is unclear what they do, this may influence how bettas will engage in future fights. Thanks to the betta’s renowned martial prowess, the researchers claim to have a “new dimension” to studying the relationship between genes and the nervous system in humans.

Given the complex personalities among bettas, and their capacity to feel happy, sad, or bored, they should be given far more than a cup or vase to live in: Not unlike humans, they prefer more space, more decor, and cleaner water, even if they can otherwise tolerate less than ideal conditions.