Education logo

Cyanobacteria, Tiny Microorganisms That Changed Our World.

Our planet is estimated to be 4.5 billion years old. It took a long time for the molten Earth to cool down from its violent beginning, but as it cooled the new conditions allowed the first rain to fall from the sky which began forming the oceans and lakes.

By A B ForbesPublished 2 months ago 3 min read
Image by Bernd Hildebrandt from Pixabay

British spelling.

Scientists believe that water was present as the Earth was being formed, and that massive amounts of incoming asteroids and comets also contributed to the water on our planet.

One estimate for the total amount of salt and fresh water on the Earth is 1,368,000,000 cubic kilometres, that water covers just over 70% of the surface of our planet

Photo by Sean Oulashin on Unsplash

Around 3.5 to 4 billion years ago some elements came together in the oceans and formed the key substances which would eventually see the creation of primitive bacteria the first life on our planet.

These early organisms came into existence at a time when the atmosphere was made up of mostly nitrogen and carbon dioxide gases.

Fossil stromatolites have been found in western Australia dating back 3.5 billion years, their columns were constructed by Cyanobacteria a single-cell photosynthesising microbe.

They used the energy of sunlight to drive photosynthesis, and one of the end products of that process is oxygen. The atmosphere of the Earth now contains 21% oxygen, 78% nitrogen and a few other gases in small amounts.

The new conditions with oxygen in the atmosphere was bad news for the life that came before Cyanobacteria, it is thought that most of them would have died off.

Over a very long period, the element oxygen accumulated in lakes, oceans, and the atmosphere. That was a game-changer for the development of life and eventually led to a big leap in animal evolution and diversity. However, it must be said that it is not yet fully understood how primitive life got started on our amazing world.

The evolutionary path for life on Earth has been very long but at last, we humans have arrived. Some animals have evolved to be stronger, larger and faster than we are and some can fly, many never leave the water, but what sets us apart is that we have developed the most advanced brain.

That amazing brain has given us the intelligence, curiosity and ability to carry out science which is providing us with a better understanding of the Universe and life itself.

By frank mckenna on Unsplash

You are a very advanced life form but why are you here? Evolution is thought to be the reason. Personally, I cannot see a more plausible reason for our existence.

Evolutionary biologists agree that all living species including ourselves are descended from the first simple organisms that lived on our planet billions of years ago.

As I said, primitive life can be traced back at least 3.5 billion years. Over countless generations, small modifications have taken place, and the small changes which are more favourable to life are more likely to be passed on to the next generation.

This process has been playing out since the first life appeared on our planet. It is called natural selection, this is the reason you are here reading this article.

Our lives are too short for us to see the small evolutionary changes taking place in populations. But one thing that evolution needs is long periods of time.

End of the main article.


We can only imagine what our early ancestors were thinking as they gazed up at the night sky, were they curious as to what the heavens had to hide?

Now it is very different as we have developed sophisticated telescopes and other specialised scientific instruments that are helping to reveal some of the secrets that the Universe holds.

Simple life forms were living on our planet almost 4 billion years ago, since that time billions of animal species have existed, and millions of species are still alive today.

The evolutionary path for life has been long but at last, we have arrived. Our highly developed brain has given us intelligence and curiosity, now we can try and make sense of our existence.

You may find a few of my articles regarding the Universe and life interesting and educational. Regards


About the Creator

A B Forbes

I hope you find some of my articles interesting.

Our highly developed brain has given us intelligence and curiosity, now with the help of sophisticated scientific instruments, we can try and make sense of the Universe and our existence.

Reader insights

Be the first to share your insights about this piece.

How does it work?

Add your insights

Comments (1)

Sign in to comment
  • A B Forbes (Author)2 months ago

    Author. My articles are written for people with an average understanding of the universe and life. We are not all experts. I hope you gain some knowledge if you decide to read them. Regards.

Find us on social media

Miscellaneous links

  • Explore
  • Contact
  • Privacy Policy
  • Terms of Use
  • Support

© 2023 Creatd, Inc. All Rights Reserved.