Even the most seemingly simple cells are capable of complexity.
For generations, we have been studying the microscopic cells of the world to gain a better understanding of how life operates. But finding that a single-celled organism is capable of passing a complex learning test without a brain or any neurons to speak of is astounding, to say the least.
How can life be so simple yet so complex?
How studying single-celled organisms has shifted our knowledge set
Studying single-celled organisms is about so much more than just understanding germs; it has rewritten the rulebook for how life on Earth exists.
Science used to believe that life on our planet was set in stone, with only two types of basic forms of life, bacteria and eukaryotes, which are complex organisms, i.e., us. But we now understand that a third type exists, Archaea, which acts like bacteria but is far more complex.
The fact that we have vast amounts of oxygen in our atmosphere can be attributed to single-celled organisms.
Roughly 2.4 billion years ago, the single-celled Cyanobacteria began to produce oxygen through photosynthesis, eventually creating an air-rich environment that allowed us, and other species, to evolve over time.
We have devastated life on our planet, but conservation is making a comeback
Our collective progress as a society has come at a cost.
Through industrialization, we have ravaged parts of the planet that are crucial for some animal species, pushing them to the brink of extinction. But as we pull back, nature has a chance at healing through natural regeneration.
Thanks to significant conservation efforts, the tallest bird in the UK is making a triumphant comeback.
We now understand how every step in the evolutionary line of life is crucial to the planet.
From tiny single-celled organisms to the more dangerous predators found in the Amazon, life of all forms is pushing back against human-led devastation. A nearly extinct type of crocodile has been repopulating in Laos, thanks in no small part to the efforts of locals.
But how can microscopic forms of life affect our thinking patterns about how the world around us behaves?
A study, “Associative learning in the protozoan Stentor coeruleus,” published in the bioRxiv preprint scientific repository, has made a remarkable discovery about how single-celled organisms are able to learn.
The secrets about associative learning in cells have been revealed
The secrets about some forms of animal life on our planet are being revealed. From river predators that have been hidden for decades to the more recent discovery made about how single-celled organisms can actually learn without brains or even neurons, life sure is strange.
Researchers were studying the single-celled Stentor coeruleus organisms when they noticed something.
The team found that these microscopic organisms are capable of what is known as Pavlovian associative learning, something we used to think was only possible with a brain, but these organisms broke the rule book.
Human beings are not the only ones capable of complex learning
The researchers found that these single-celled Stentor coeruleus organisms learnt to associate a neutral stimulus with a protective response.
This suggests that learning is a biological process that does not require a brain or even neurons to undertake, proving that even the most seemingly simple forms of life are capable of so much more than we thought. How might this change our perception of learning in ourselves?
Without the efforts of science, these types of remarkable discoveries would not be possible.
So, while we unearth new findings about our brains, this study has found that learning does not need a complex brain or neurons of any kind, only a single cell to form the basis of learning.