Single-Celled Slime Mold Can Learn And 'Remember'

Scientists find that even single-celled organisms, with no nervous systems, can learn.

It is important for the animal world to learn as well as remember from experience and adaptations to the dangerous world. However, people have never felt that single-celled organisms may be able to actually learn.

Scientists studied bacteria or other single-celled organisms to check if they learnt. Hence, they opted to study a protist, or "slime mold", which is a giant cell in shady, cool areas. Studies show that it has been able to solve mazes, avoid traps and maximise its consumption.

Scientists released  bitter, but harmless, substances through which the slime mold had to go through so that it could reach a food source. They made a "bridge" of either quinine or caffeine. Another control group had to cross a "bridge" that was not coated with the bitter materials.

At first, the molds resisted travelling through quinine or caffeine, but once they "realized" that they were harmless substances, they could cross quickly. Once they were confronted with the substance many times, they learnt not to fear them.

However, after a couple of days without contact with the substance, the mold returned to its initial distrust.

It is interesting that scientists could observe a form of habituation, or "rudimentary learning." Although it exists in all animals, it has not been observed in a non-neural organism like a slime mold.

Experts understood that the single-celled organisms are able to determine what is harmful and what is not, and they "remember" it for long.

The findings were published in the April 27 issue of the journal Proceedings of the Royal Society B: Biological Sciences.