These strange fossils that have intrigued scientists for decades are neither plants nor animals, but a bit of both. A “strange fusion” of life and a major discovery.
If scientific discoveries are regular in the field of biology, some make an impression. Hard to believe, but it still happens in our time to discover new species, to see them reappear when they were presumed extinct, or even sometimes to completely review knowledge about a form of life. A study published in the international scientific journal “Review of Palaeobotany and Palynology” recently looked at fossils whose nature has defied scientific certainty for decades.
These fossils, traced back over a very long period ranging from nearly half a billion years ago to the present day, correspond to a form of life that is neither animal, nor plant, nor even bacterial. And it’s not a mushroom either! They have been cited in several studies in the past without ever having been clearly identified. If they could have been considered in the 1960s as forms of familiar organisms (shells, algae, spores, etc.), “their biological affinity has never been established”, explains Andreas Koutsodendris, co-author of the new study.
It was only in 2012 that paleontologists Bas van de Schootbrugge and Paul Strother realized that these fossils could be traces of another form of life. Some in fact look strangely like fingerprints. And the two researchers of the time will immediately make the connection with something known: euglenids, a form of life resulting from a fusion of a group of living beings that we are still discovering today. When they are subjected to stress, they envelop themselves in a protective cyst, in which they plunge into a state of dormancy, a form of drowsiness or slowed life. And this cyst is similar to a fingerprint too!
That’s where the new study comes in: It not only helped confirm that the mysterious fossils were a form of euglenids, aquatic organisms that began to distinguish themselves from other life forms about a billion years ago years. But it also established a chronology of these living beings that could go back to the time of the dinosaurs! These life forms have probably “endured and survived all the major extinctions on the planet,” says an enthusiastic Van de Schootbrugge.
It must be said that our astonishing euglenids are capable of obtaining energy through photosynthesis, like a plant, while at the same time consuming other living beings, like an animal! Enough to make them very resilient. Now, it is a matter of learning more about these living beings which could tell us more about the mass extinction which caused 95% of species to disappear around 250 million years ago.
