Could this unsolicited warning be anticipating, paradoxically, a fossil announcement on Mars? What actually do they mean by false fossils? Let’s find out
When looking for signs of life on Mars, we often come across interesting things that seem to point to some kind of biological life, including objects that some anomaly hunters – through photographs taken by the rovers – have interpreted as fossils, fungi, or even crabs. However, now a group of scientists warns that we must be on the lookout for “false fossils” that may be abundant on the red planet.
According to astrobiologist Sean McMahon of the University of Edinburgh and geobiologist Julie Cosmidis of the University of Oxford in the UK, scientists will need to be on the lookout for non-biological mineral deposits that closely resemble fossils.
In a new paper, the pair described dozens of nonbiological or abiotic processes that can produce pseudo-fossils – fossil-like structures of microscopic organisms like those that once existed on Mars.
“At some point, a Mars rover is almost certain to find something that looks a lot like a fossil, so it is vital to be able to confidently distinguish them from structures and substances produced by chemical reactions,” McMahon said. “For every type of fossil that exists, there is at least one non-biological process that creates very similar things, so there is a real need to improve our understanding of how they are formed.”
This notion is not exactly surprising. Mars is an absolute feast for pareidolia and conspiracies. All it takes is a suggestive-looking stone and rumors break out. However, it is also true that, since we do not know the life that could have emerged on this planet, the opposite could happen – with fossils that could be interpreted as simple rocks and be overlooked. After all, even here on Earth, we have a hard time differentiating between really old rocks and fossils of ancient microbes.
But, if we go into the analysis of any potential microfossils on Mars knowing the processes that can produce pseudo-fossils, we have a better chance of accurately interpreting what we are seeing.
Many physical processes associated with weathering and the deposition of sedimentary layers can produce rocks that eerily resemble fossils.
Another mechanism is the chemical garden, in which mixing chemicals can produce structures that appear biological. Also, many different types of minerals can combine to produce pseudo-fossils known as biomorphs, which appear surprisingly biological.
The researchers also point out that more work, perhaps even experimentation, in the chemistry and physics of Mars could reveal the odd unknown natural processes and shed more light on how such formations might occur. This work might even help us better understand Earth’s rock and fossil record.
“We have been fooled by processes that mimic life in the past,” Cosmidis said. ‘On many occasions, objects that looked like fossil microbes were described in ancient rocks on Earth and even in meteorites on Mars, but upon closer examination, they turned out to have non-biological origins. This article is a warning in which we ask for more research on the processes of imitation of life in the context of Mars, to avoid falling into the same traps over and over again.
Aiming at the exploration of Mars taking these factors into account, could not only help us to better understand its nature but also establish a clearer geological-biological differentiation process that seriously considers the possibility that there really are Martian fossils waiting to be discovered.
Source: University of Edinburgh