عربي English Türkçe اردو فارسى
Logo
Latest News
Varieties

Freshwater Fish Can Do Math, New Study Suggests

A researcher from University of California, Davis catches hatchery salmon from a tank to measure their size, as part of a joint project between ecologists and rice farmers trying to reclaim the great flood plains of the Sacramento River for salmon habitat, in Robbins, California, US, February 4, 2022. REUTERS/Carlos Barria
A researcher from University of California, Davis catches hatchery salmon from a tank to measure their size, as part of a joint project between ecologists and rice farmers trying to reclaim the great flood plains of the Sacramento River for salmon habitat, in Robbins, California, US, February 4, 2022. REUTERS/Carlos Barria
TT
20
TT

Freshwater Fish Can Do Math, New Study Suggests

A researcher from University of California, Davis catches hatchery salmon from a tank to measure their size, as part of a joint project between ecologists and rice farmers trying to reclaim the great flood plains of the Sacramento River for salmon habitat, in Robbins, California, US, February 4, 2022. REUTERS/Carlos Barria
A researcher from University of California, Davis catches hatchery salmon from a tank to measure their size, as part of a joint project between ecologists and rice farmers trying to reclaim the great flood plains of the Sacramento River for salmon habitat, in Robbins, California, US, February 4, 2022. REUTERS/Carlos Barria

Some primates, bees, birds, and now freshwater fish: the circle of animals with mathematical skills is widening. A recent study has found that some types of fish have mathematical abilities such as addition.

It’s scientifically proven that all vertebrates, and even some invertebrates have the ability to measure quantities- a vital function creatures need when searching for food, avoiding predators, moving in group, and mating.

But scientists are now investigating how these creatures can quantify: is it a simple estimate based of the object’s size, or they are actually able of doing accurate math? Former studies showed that some monkeys, parrots, pigeons, spiders, and bees are capable of processing numerical information, and even performing simple mathematical functions.

A recent study at the University of Bonn’s Institute of Zoology revealed that some types of fish such as cichlids, stingrays, and zebra mbuna have some math skills. The findings were published in the journal Scientific Reports.

Eight fish of each type underwent hundreds of tests in large tanks specially designed to monitor their performance. In the tanks, the fish were trained to associate the blue color with addition (+1), and the yellow color with subtraction (-1).

Then, the scientists spread cards featuring blue and yellow shapes, and made the fish choose from two sliding doors each featuring a card with different number of shapes; one of the two doors has the correct answer.

For instance, when a fish sees a card with three blue shapes, it is supposed to swim towards the door with the card featuring four blue shapes as blue refers to addition. On the contrary, if the fish sees a card featuring four yellow shapes, it should head towards the door with the card featuring three yellow shapes, one shape lesser than the original card, as yellow refers to subtraction.

When the fish passed through the correct door, it was rewarded with its favorite food. The study showed that six of the mbuna fish and four stingrays successfully linked blue to (+1), and yellow to (-1).

According to researchers, the mbuna fish needed more time to select the door, and mbunas and stingrays remembered addition more easily than subtraction.

The researchers said their work unveils new cognitive abilities that could help mbunas and stingrays recognize other fishes from the same species based on their appearance, by counting the lines or spots on their bodies.

Most Viewed

 
Varieties

Nigerian Farms Battle Traffic, Developers in Downtown Abuja

Developers fill in farmland despite regulations protecting these areas as rare green spaces in Abuja. OLYMPIA DE MAISMONT / AFP
Developers fill in farmland despite regulations protecting these areas as rare green spaces in Abuja. OLYMPIA DE MAISMONT / AFP
TT
20
TT

Nigerian Farms Battle Traffic, Developers in Downtown Abuja

Developers fill in farmland despite regulations protecting these areas as rare green spaces in Abuja. OLYMPIA DE MAISMONT / AFP
Developers fill in farmland despite regulations protecting these areas as rare green spaces in Abuja. OLYMPIA DE MAISMONT / AFP

Under the din of traffic from the highway bridge that cuts over his fields, Bala Haruna inspects corn, cassava and okra on his family farm.

A pump pulls up water from a nearby stream and is diverted through trenches dug through cropland wedged between four-lane roads -- fields which were here long before the nearby hotel, the imposing national mosque or any of the high-rises that make up downtown Abuja were even dreamed up.

"There were no buildings here," Haruna, 42, told AFP, reminiscing over his childhood as birds chirped and frogs croaked.

The urban farms dotting Nigeria's capital show the limits of the top-down management the planned city is known for -- oases scattered around pockmarked downtown that has long expanded outward faster than it has filled in.

They owe much of their existence to the fact that they lie in hard-to-develop gulches along creek beds. Even roads built through them over the years tended to be elevated highway overpasses.

That fragile balancing act, however, is increasingly under threat, as developers fill in farmland despite regulations protecting these areas as rare green spaces in a city known for concrete sprawl.

On the other side of the overpass, the future has arrived: the vegetation abruptly stops and temperatures suddenly rise over flattened fields razed by construction crews.

Local farmers said the people who took the land three years ago provided no documentation and only gave the eight of them 300,000 naira to split -- a sum worth only $190 today after years of rampant inflation.

Much of the farmland in and around downtown is supposed to be a municipal green space, with neither farms nor buildings on it.

But enforcement of the decades-old Abuja master plan is ripe with abuse and lack of enforcement, said Ismail Nuhu, urban governance researcher who did his PhD on the capital's urban planning.

Adding to the sense of precarity is that the land, on paper, belongs to the government.

"Politicians still use it to grab lands, just to say, 'Oh, according to the master plan, this is not to be here'," no matter what the document actually says, he told AFP, adding that, technically, even the presidential villa is not located where it is supposed to be.

Nyesom Wike, the minister of the Federal Capital Territory, which includes Abuja, recently told reporters he would "enforce" the 70s-era master plan by building roads and compensating and evicting settlements that stand in the way.

FCT officials including Wike's spokesman did not respond to requests for comment.

Urbanizing country, not enough jobs

The farms have provided steady employment -- a lifeline for some as the rapidly urbanizing country fails to produce enough jobs. A recent opening for 10,000 government jobs saw 450,000 applicants, according to local media.

"Having a green space... in a very thick, populated city like Abuja does a lot of good," said retiree Malik Kuje Guni, who started farming three years ago to supplement his pension.

While tens of thousands of residents pass by the farms each day without second thought, Guni, when he was working as a civil servant, would often come down to visit, enjoying the shade and fresh air.

Now tilling a potato plot of his own, "I can come down, work, sweat," the 63-year-old said. "I have hope something will come out of it."

A few blocks over, squat, informal houses made of wood and sheet metal give way to a field of sugarcane, corn and banana trees. Glass-paneled highrises, half-finished construction and the imposing Bank of Industry tower above.

The crops give way to land cleared by developers a few months ago, some of whom pushed into Godwin Iwok's field and destroyed his banana trees.

Iwok, who quit his security job 22 years ago to make more money as a farmer, has had parts of his fields destroyed twice in the past two years, neither time with compensation.

To Guni, the farms represent the city's rural heritage. Despite decades of government promises to relocate Nigeria's capital from the crowded, congested mega-city of Lagos, the move only occurred in 1991.

But neither Iwok, 65, nor Haruna want their children to continue their increasingly precarious line of work.

"I wouldn't want my children to stand under the sun as I did," Iwok told AFP.

"I only use what I'm getting here... to make sure my children go to school."