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Scientists say they've discovered cookie-shaped fossils in Gabon that may represent the earliest-known multicellular life, dating back 2.1 billion years. But when you go that far back, claims about fossilized life get complicated.
For one thing, we're talking about multicellular life: The traces of microbial life appear to go even further back in time - to 3.45 billion years ago, based on the way that mats of organic material have built up in ancient sediment. In the multicellular category, the oldest candidate has been a 2 billion-year-old, centimeter-scale, coil-shaped fossil known as Grypania spiralis, which might have been a giant bacterial or algal creature.
The new discoveries, described in today's issue of the journal Nature, show more evidence of structure and measure as large as 12 centimeters (4.7 inches) in size. "On the surface, the fossils resemble irregularly shaped cookies with split edges and a lumpy interior," the researchers, led by Abderrarazak El Albani of the University of Poitiers, report in a news release.
El Albani and his colleagues collected more than 250 fossils from a well-known geological formation in the West African country of Gabon, and put them through rounds of micro-CT scans to chart their 3-D structure. Based on that structure, the researchers deduce that the organisms were built up through cell-to-cell signaling - and not merely deposited together as a microbial mat.
© CNRS Photothèque / Kaksonen
Many of the fossils found in Gabon measure more than an inch wide. Watch a video report about the discovery from TODAY's Dara Brown.
"The relative complexity of the fossils ... lead El Albani and colleagues to conclude that they are unlike any living bacterium," Philip Donoghue and Jonathan Antcliffe of the University of Bristol write in a Nature commentary on the research. However, Donoghue and Antcliff say additional work will have to be done to confirm that these cookies are more than mere assemblages of one-celled organisms, as well as to verify they were living 2.1 billion years ago rather than during a later age.
The 2.1 billion-year mark is significant because scientists think Earth's atmosphere made a major transition around 2.4 billion years ago. Before that time, there appears to have been no oxygen in the air. Even 2.1 billion years ago, "the atmosphere was still a toxic mix of greenhouse gases, with oxygen making up only a few percent of modern levels," Donoghue and Antcliff note.
"This bacterial world was undergoing the greatest episode of climate change in the history of the planet: pumping out oxygen, drawing down carbon dioxide, slowly transforming the Earth into the world we know," they say.
The bottom line is that these rock-hard cookies could shed light on how life as we generally know it arose from the alien-seeming, one-celled organisms that predated our planet's Great Oxidation Event. But this is still just a tiny piece in a puzzle that will take years of hard work to put together.
In addition to El Albani, the authors of the Nature study, "Large Colonial Organisms With Coordinated Growth in Oxygenated Environments 2.1 Gyr Ago," include Stefan Bengtson, Donald E. Canfield, Andrey Bekker, Roberto Macchiarelli, Arnaud Mazurier, Emma U. Hammarlund, Philippe Boulvais, Jean-Jacques Dupuy, Claude Fontaine, Franz T. Fursich, Francois Gauthier-Lafaye, Philippe Janvier, Emmanuelle Javaux, Frantz Ossa Ossa, Anne-Catherine Pierson-Wickmann, Armelle Riboulleau, Paul Sardini, Daniel Vachard, Martin Whitehouse and Alain Meunier.
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Way back in the seventies (1970s, that is) a friend of mine produced, from an Illinois coal mine, a piece or Iron Pyrite (sometimes called "fool's gold") a formation (for want of a better word) that was bilaterally symmetrical and looked to me like a fossil nautilus. Those, you will remember, are shelled cephalopods (like squid and octopus) with short tentacles. They are very old life form and are known from coal deposits. I took the thing to a geologist at the Field Museum of Natural History and was told that it did not represent a fossil animal. but was just a natural crystalization of pyrite. Despite the appearance of a spiral shell and lateral appendages, he said that there was no animal matrix inside the thing.
What this told me is that the interpretation of "fossils" can be very subjective and is not to be done without a deep knowledge of the field. The Precambrian "cookies" may turn out to be multicelled organisms, or clusters of one-celled organisms, or simply crystalizations that were never alive. Even the article we read allows for that.
"That nothing became something to evolve a brain into self explanation goes for insane! .... in the absolutely impossibility of dimensionally formed MATTER -- but it did --I guess we're ALL a product of insanity.
Unfortunately, the debate around creationism is not innocent - it has hugely important implications for how we view and treat the Earth now. For instance, if you believe that the ecosystem evolved over billions of years, you must also see that everything is extremely linked together. It is a SYSTEM, not a species in isolation.
If you think that everything was created a short time ago, especially by a kind of interventionist God, then you might be deluded into thinking that we (humans) are in isolation. Yes, ironically, the same people who want to push creationism generally have the least respect, appreciation and love for God's actual creation!!
So instead of acting responsibly and in accord, and dealing with the challenges we have together as we need to, we waste time and money arguing...And what is at the core of the creationist philosophy? THEY ARE NOT RESPONSIBLE ! Yes, in so many ways, the whole movement is a way of getting out of taking any personal or collective responsibility for what we do and have created.
But what is the very most poignant and powerful gift we have from God? Our own Free Will, our own ability to take responsibility and to act in ways which respect and honor creation…or not! So what appears to the “believers” to be the high and sure moral ground, firmly planted in the unwavering truth of the Bible and other similar texts is in fact a path away from their humanity and their relationship with God.
This same argument of creation versus evolution goes nowhere for either side since if you trace either to side to the beginning point (since most people need a linear time line to grasp) it still boils down to who created the universe versus who created god.
To me, I have no problem with the universe being created from nothing in the singularity known as the big bang or time being a construct of that process and not being linear at all. Regardless, it's pointless to think about what caused or may have existed before the big bang because any evidence of anything before it would have been totally destroyed in the process. Sometimes the best answer is we don't know and will never know and just end it at that.
If faith floats your boat, then go with it. At least it somewhat fills in a lot of the blanks and if that helps you in your life, then that's great. I prefer science, but that requires accepting that there are lot of questions which will never have answers, which is hard for people who do like closure. I'm OK with not knowing that. The most we ever learn is how much we don't know. I believe that's what most people refer to as wisdom regardless of your slant.
Uhhhh, everything that is known to man on the periodic table of elements, from deuterium to iron was created by the death of a star. In other words a Supernova. You create deuterium by smashing two protons together. Smash more protons into deuterium and you get carbon, helium, hydrogen, oxygen and so forth until you get to iron. Cool huh? So technically we are all made from star stuff.