This is an interesting question that is not so easy to answer. All organisms consist of living cells. Although it is difficult to determine exactly when the first cells appeared, geologists’ best guess is that it happened at least 3.8 billion years ago. So how much life has existed on this planet since the first cell on Earth? So how much life will exist on Earth?

In a new study published in the journal Current Biology, my colleagues at the Weizmann Institute of Science and Smith College and I set out to answer these big questions.

Carbon in the World

Approximately 200 billion tonnes of carbon are sequestered each year through so-called primary products. During primary production, inorganic carbon, such as carbon dioxide in the atmosphere and bicarbonate in the ocean, is used to obtain energy and create the organic molecules needed by life. Today, the most important participant in this process is oxygenic photosynthesis, in which sunlight and water are the main components.

However, unraveling the historical rates of the primary product has been a difficult task. Instead of a time machine, scientists like me rely on clues left in ancient sedimentary rocks to recreate past environments. In the case of the primary product, the isotopic composition of oxygen in the form of sulfate in ancient salt deposits allows such predictions to be made.

In our study we have collected all previous estimates of ancient primary product obtained by the above method and others. As a result of this efficiency count, we were able to estimate that 100 quintillion (or 100 billion) tonnes of carbon have passed through primary products since the beginning of life.

Large numbers like these are hard to imagine; 100 quintillion tons of carbon is roughly 100 times the amount of carbon found on Earth; This is quite an impressive achievement for Earth’s primary producers.

primary product

Today, the primary product is obtained mainly by terrestrial plants and marine microorganisms such as algae and cyanobacteria. In the past, the proportion of these main participants was very different; In Earth’s earliest history, primary cropping was predominantly carried out by a completely different group of organisms that did not require oxygenic photosynthesis to survive.

Using a combination of different methods, we were able to gain insight into the times when various primary producers were most active in Earth’s past. Examples of such methods include identifying the oldest forests or using molecular fossils called biomarkers. In our study, we used this information to investigate which organisms contributed most to Earth’s historical primary product. We found that land plants probably contributed the most, despite their late emergence. However, it is likely that cyanobacteria also made the largest contribution.

general life

By determining how much of the primary product was formed and which organisms were responsible for it, we were also able to estimate how much life there has ever been on Earth. In the end, we were able to estimate that there are about 10 in existence today.³⁰ (10 trillion) cells and 10³⁹ (duodecillion) and 10⁴⁰ Cells have always existed on Earth. Source