Structures previously thought to be footprints of tiny marine animals have turned out to be fossilized communities of bacteria and algae. The finding suggests that some of the Ediacaran oceans did not yet support such animals.
Ancient fossils from Brazil, some 540 million years old, are changing one of the assumptions about the beginning of complex life on Earth. Structures previously thought to be footprints left by tiny marine animals on the seafloor have been revealed in a new study to be the fossilized remains of communities of bacteria and algae. The study is published in the journal Gondwana Research and reported on the website SciTechDaily.
The study focused on fossils from the Tamengo Formation in the state of Mato Grosso do Sul, Brazil. These fossils were previously interpreted as possible evidence of tiny animals that lived on the seafloor at the end of the Ediacaran period, shortly before the “Cambrian explosion,” when a wide variety of complex animals appeared. If the old interpretation was correct, it would be one of the earliest evidences of such tiny creatures, invertebrates less than a millimeter in size.
But the new study paints a different picture. The researchers say the structures are not burrows or signs of animal movement. They are the three-dimensional remains of microbial communities, which included filamentous algae and bacteria. This conclusion strengthens the possibility that at that time some marine environments did not yet contain enough oxygen to support the kind of small animals previously attributed to these fossils. The ScienceDirect abstract states that the evidence points to communities of algae and bacteria, not actual burrows of tiny animals. (ScienceDirect)
New technology revealed the internal structure
The study was led by Bruno Becker-Kerber, who carried out the work as a postdoctoral researcher at the University of São Paulo and the Brazilian Center for Energy and Materials Research. He is currently continuing his postdoctoral research at Harvard University. He said that using microtomography and spectroscopy, he showed that the fossils preserved cellular structures, and sometimes organic material, that corresponded to bacteria or algae that lived at the time.
The researchers used the MOGNO beamline at the Sirius facility, a particle accelerator in Brazil. The equipment allowed them to examine fossils ranging in size from a few micrometers to a few millimeters, and scan their internal structure without destroying the samples. In some cases, “zoom tomography” was performed, which means focusing on a small detail within the sample and examining it at the nanometer scale.
The researchers also used Raman spectroscopy, a method that allows them to examine the chemical composition of the material. The test revealed organic compounds in the walls of fossilized cells. This finding reinforced the conclusion that these are actual biological remains of bacteria or algae, and not just marks created when animals moved through the sediment.
Microbial communities instead of animals
Some of the fossils also contained pyrite, a mineral composed of iron and sulfur. Based on their shape and composition, some of the structures may represent sulfur-oxidizing bacteria. Such bacteria use sulfur as part of their metabolism, and some species in this group are relatively large compared to other bacteria and are even visible to the naked eye.
The researchers found preserved cells, cell wall divisions, coiled fibers, and organic matter in the fossils. These are features that are difficult to explain as mere signs of sediment disturbance. In addition, the fossils fell into three different size groups, suggesting that several types of organisms may have lived together in microbial communities. The larger forms resemble green or red algae, while the smaller ones may be algae, cyanobacteria, or sulfur-oxidizing bacteria.
The findings are important because they draw a more careful line between evidence of microbial life and evidence of ancient animals. Complex life was already present in the Ediacara period, but not every fossilized structure that suggests movement or burrowing is necessarily a sign of an animal. In this case, imaging technologies and chemical analysis showed that the structures themselves were preserved as biological bodies, not just traces.
A new look at the period before the Cambrian explosion
The study helps to better understand the conditions that preceded the Cambrian explosion. The Ediacara period is considered an important transitional stage in the history of life, when larger, more complex life forms appeared, but many ecosystems were still dominated by microorganisms. If the fossils from Brazil are not evidence of tiny animals, such animals may have appeared later than some researchers thought.
The scientific article, titled “Proposed Ediacaran meiofaunal burrows from Brazil are pyritized algal/microbial consortia,” was published in the June 2026 issue of Gondwana Research. According to the publication details, it was written by Bruno Becker-Kerber and colleagues, and deals with a reinterpretation of structures previously thought to be burrows of tiny animals. (ScienceDirect)
The broader significance of the study goes beyond identifying the fossils themselves. It reminds us of how difficult it is to interpret the ancient fossil record, especially when it comes to very small structures formed in ancient marine environments. Advanced technologies are now making it possible to reexamine old conclusions, and sometimes change the picture of how complex life on Earth evolved.
Short FAQ
What the new study found?
The researchers found that structures thought to be the footprints of tiny marine animals are actually fossilized communities of bacteria and algae.
How old are the fossils??
The fossils are about 540 million years old, from the end of the Ediacar period.
why is it important?
The finding changes the interpretation of the appearance of tiny animals before the Cambrian explosion, and shows that some of the previous evidence may be microbial rather than animal.
How the researchers discovered this?
They used microtomography, nanotomography, and Raman spectroscopy, which revealed cellular structures and organic material within the fossils.
More of the topic in Hayadan:
12 תגובות
To my father: "The complexity of the real world" is not of interest to these sectors, but rather the words of God Almighty. This complexity is vanity compared to them. Preoccupation with this world is out of necessity to exist (and this requires quite a few things), and also in order to fulfill the Creator's commandments. More than that – it is already abrogation of the Torah.
To Raviv: The stories written 3338 years ago about what happened 5786 years ago (and more) deal with the same thing that the measurements measure – the development of our world to its current state.
This is because of the rejection of core studies by large segments of society. Because they have been taught that there is one book that knows everything, they are not open to learning the complexities of the real world.
Why are we even trying to find a connection between a puzzle that never stops building itself based on measurements, and a folklore story that was written five thousand years ago according to the 'scientific' concepts of the time?
There is a theory that the words "the great crocodiles" (on the fifth day of creation) refer to dinosaurs. The Torah does not use the word "dinosaurs" for the simple reason that this word was invented after the Torah was written.
To this day I don't understand how the world has only existed for 5,700 years... It's interesting that dinosaurs are not mentioned even once in the Torah... because according to the Torah, all creatures were created at the creation of the world in Genesis.
Happy holiday.
Abba Eban once said in a television series he created about the history of the Jewish people that civilization began thousands of years ago, not creation.
Response to Anna and anyone interested: Every day in the Torah in Genesis, about four billion and three hundred million years!
https://youtu.be/HPEBC8wDt_M
A scientific fact that agrees perfectly and precisely with the Torah!
The contradiction between the Torah and science is not new. Even in the time of the Greeks, there was a debate between us and them, whether the world was created (as written in the Bible) or pre-existent (as it was visible to the eyes).
In my humble opinion, these are simply two different points of view – essential and technical: Essential – the world was created so that we could use it and improve ourselves and it, and creation is just a small detail in this; Technical – the world has evolved over billions of years, animals a few million, and organized human society – a few thousand.
And one more thing: Happy holiday!
According to science, between the creation of the universe (the Big Bang) and the formation of the sun, about 9 billion years passed, and that's only three days in the story of creation, you have to add a few zeros. Also according to Genesis 1, the Earth existed from the first moment, and in fact - it was created only after the sun was created.
Every year in the Bible = 10,000 years in evolution.
The world has only existed for 5786 years, so does it make sense that fossils are millions of years old?
The miscalculation is that what makes these fossils look so old is the sudden flood that happened in the Flood era.
Interesting thank you