Yes, it took 300 years to finally figure out how bacteria ‘see’ their world and they do it in a remarkably similar way to us. The team of British and German researchers revealed how bacterial cells act as the equivalent of a microscopic eyeball or the world’s oldest and smallest camera eye.
The team was studying the bacteria Synechocystis. It’s not an aquatic bacterium, since it can’t swim, but it does have tiny hair-like cilia, that allow it to crawl its way across wet surfaces like rocks. Synechocystis uses photosynthesis to make energy for itself, and so it’s dependent on the sun.
Experts have long known that Synechocystis can sense light and will haul itself towards a light source. But exactly how it perceives that light was unknown. Scientists surmised that Synechocystis might have tiny receptors along the outside wall of its cells that measure different light levels on either side of its body.
Another possibility is that Synechocystis may have a system that measures the chemical reactions of its environment to light.
According to the new findings published in eLife, the bacteria could see the world just like us.
The idea that bacteria can see their world in basically the same way that we do is pretty exciting.
stated lead researcher Conrad Mullineaux, professor of microbiology.
When the research team put the bacteria on a surface that had a gradient of light, the bacteria moved randomly. E. coli bacteria, on the other hand, have sensors that respond to chemical stimulus, and thus would have sensed the gradient and accumulated in the area most comfortable for them. Give the Synechocystis one light source, though, and they’ll move right towards it.
‘The cells act as tiny spherical lenses,’ the researchers wrote in their study. Light that shines in the front is focused on the back cell wall. On the back wall, ‘light-detecting molecules called photoreceptors,’ respond to the light, letting the bacteria get a blurry and basic picture of the world.
The complex process of seeing explained by the experts is exactly how the human eye works. The obvious conclusion is that the bacteria don’t just have eyeballs, they are eyeballs.
The funny thing is that it took scientists’ so long to figure this out. On that note, professor Mullineaux concludes the findings, stating that:
No one else noticed it before, despite the fact that scientists have been looking at bacteria under microscopes for the last 340 years.