Schoolboy explodes goldfish memory myth
February 18, 2008
A 15-year-old South Australian school student
has busted the myth that goldfish have a three second memory.
Rory Stokes, from the Australian Science and
Mathematics School in Adelaide, conducted an experiment to test
the commonly held theory that goldfish have short memory spans.
He was also keen to open people's minds to the
cruelty of keeping fish in small tanks.
"We are told that a goldfish has a memory span
of less than three seconds and that no matter how small its tank
is, it will always discover new places and objects," Rory said.
"I wanted to challenge this theory as I
believe it is a myth intended to make us feel less guilty about
keeping fish in small tanks."
Rory's experiment involved teaching a small
group of fish to swim to a beacon by establishing a memory
connection between the beacon and food.
Over a period of three weeks, he placed a
beacon in the water at feeding time each day, waited 30 seconds
and then sprinkled fish food around the beacon.
The time taken for the fish to swim to the
beacon reduced dramatically, from more than one minute for the
first few feeds to less than five seconds by the end of the
Following the initial three-week period, Rory
removed the beacon from the feeding process.
Six days later, he once again placed the
beacon in the water and despite not seeing it for almost a week,
the fish swam to the beacon in 4.4 seconds, showing they had
remembered the association between food and the beacon for at
least six days.
"My results strongly showed that goldfish can
retain knowledge for at least six days," Rory said.
"They can retain that knowledge indefinitely
if they use it regularly."
Rory also conducted a number of
sub-experiments which showed that goldfish were capable of
negotiating a simple maze, having them move onto a second beacon
if they found no food at the previous one.
"My experiments showed that goldfish have the
mental capabilities to learn and remember fairly complex
concepts and they can retain that knowledge for at least a
number of days," he said.
Australian Science and Mathematics School
principal Jim Davies said the series of experiments were an
excellent example of science investigation made fun.