Creationism in Crisis
Remains of Earliest Eukaryote Organisms
From 1.0 - 1.6 Billion Years Ago
Image: Orchestrated in MidJourney by TA 2023
Remains of Earliest Eukaryote Organisms
From 1.0 - 1.6 Billion Years Ago
Artist’s imagination of what a planktonic stem group eukaryote of the ‘Protosterol Biota’ may have looked like. Based on molecular fossils, organisms of the Protosterol Biota inhabited the oceans about 1.6 to 1.0 billion years ago and are our earliest known ancestors.
Image: Orchestrated in MidJourney by TA 2023
Artist's reconstruction of early eukaryotes on marine sediment.
The great thing about the Theory of Evolution or descent with modification, is that it predicts simpler ancestry as you go further back into archaeological history, and this is just what we find as we dig down into the geological column. Creationists have never managed to come to terms with that evidence other than the almost unbelievably childish notion that the more advanced species could run faster so got higher up the mountains as the encroaching genocidal flood grew deeper.
Which of course doesn't explain why fossilised shellfish are found on tops of mountains.
And nor does it explain why the fossils are arranged so neatly in sedimentary strata that creationists also claim was all produced by that single global flood event, since dead bodies would float away from the mountainsides where they supposedly drowned.
And, of course it doesn't explain the arrangement of the species which don't run away from a flood, like marine species and single-celled organisms, and yet, there they are in the geological column, looking for all the world as though the simpler, more primitive organisms got buried below the more advanced forms.
And now we have the spectacular discovery that strata laid down between 1.6 and 1.0 billion years ago contains molecular fossils produced by the earliest (and simplest) single-celled eukaryote organisms, just where and when the TOE predicts they should be!
The chemical fossils are in the form of "protosteroids", i.e., intermediate stages in the production of sterols such as cholesterol that almost all modern eukaryotes produce. These intermediate may have been the end product in these early eukaryotes in which the modern metabolic pathways were still evolving, but the fact that they were being produced by these early eukaryotes suggests that amongst them was the stem species from which all later eukaryotes have descended.
The discovery was announced a few days ago in the journal Nature, by an international team of researchers, including GFZ geochemist Christian Hallmann of the GFZ German Research Centre for Geosciences, Potsdam, Germany, and a news release from GFZ:
Newly discovered biomarker signatures point to a whole range of previously unknown organisms that dominated complex life on Earth about a billion years ago. They differed from complex eukaryotic life as we know it, such as animals, plants and algae in their cell structure and likely metabolism, which was adapted to a world that had far less oxygen in the atmosphere than today. An international team of researchers, including GFZ geochemist Christian Hallmann, now reports on this breakthrough for the field of evolutionary geobiology in the journal Nature.Sadly, the team's paper in Nature is behind an expensive paywall but the abstract is available.
The previously unknown “protosteroids” were shown to be surprisingly abundant throughout Earth´s Middle Ages. The primordial molecules were produced at an earlier stage of eukaryotic complexity — extending the current record of fossil steroids beyond 800 and up to 1,600 million years ago. Eukaryotes is the term for a kingdom of life including all animals, plants and algae and set apart from bacteria by having a complex cell structure that includes a nucleus, as well as a more complex molecular machinery.
Unprecedented glimpse of a lost worldThe highlight of this finding is not just the extension of the current molecular record of eukaryotes. Given that the last common ancestor of all modern eukaryotes, including us humans, was likely capable of producing ‘regular’ modern sterols, chances are high that the eukaryotes responsible for these rare signatures belonged to the stem of the phylogenetic tree.
Christian Hallmann, co-author
GFZ German Research Center for Geosciences
Potsdam, Germany
This “stem” represents the common ancestral lineage that was a precursor to all still living branches of eukaryotes. Its representatives are long extinct, yet details of their nature may shed more light on the conditions surrounding the evolution of complex life. Although more research is needed to evaluate what percentage of protosteroids may have had a rare bacterial source, the discovery of these new molecules not only reconciles the geological record of traditional fossils with that of fossil lipid molecules, but yields a rare and unprecedented glimpse of a lost world of ancient life. The competitive demise of stem group eukaryotes, marked by the first appearance of modern fossil steroids some 800 Million years ago, may reflect one of the most incisive events in the evolution of increasingly complex life.
What the Nobel laureate thought impossible...Almost all eukaryotes biosynthesise steroids, such as cholesterol that is produced by humans and most other animals. Due to potentially adverse health effects of elevated cholesterol levels in humans, cholesterol doesn’t have the best reputation from a medical perspective. However, these lipid molecules are integral parts of eukaryotic cell membranes where they aid in a variety of physiological functions. By searching for fossilised steroids in ancient rocks, we can trace the evolution of increasingly complex life.
Benjamin J. Nettersheim, co-first author
Research School of Earth Sciences
The Australian National University
Canberra, Australian Capital Territory, Australia
And MARUM–Center for Marine Environmental Sciences and Faculty of Geosciences
University of Bremen, Bremen, Germany
Nobel laureate Konrad Bloch had already speculated about such a biomarker in an essay almost 30 years ago. Bloch suggested that short-lived intermediates in the modern biosynthesis of steroids may not always have been intermediates. He believed that lipid biosynthesis evolved in parallel with changing environmental conditions throughout Earth history. In contrast to Bloch, who did not believe that these ancient intermediates could ever be found, Nettersheim started searching for protosteroids in ancient rocks that were deposited at a time when those intermediates could actually have been the final product.
But how to find such molecules in ancient rocks?
Scientists had overlooked these molecules for decades because they do not conform to typical molecular search images.We employed a combination of techniques to first convert various modern steroids to their fossilised equivalent; otherwise we wouldn’t have even known wat to look for.
“Once we knew our target, we discovered that dozens of other rocks, taken from billion-year-old waterways across the world, were oozing with similar fossil molecules.
Profess Jochen J. Brocks, co-first author
Australian National University
Canberra, ACT, Australia
One of the most profound ecological turning points in our planet’s history
The oldest samples with the biomarker are from the Barney Creek Formation in Australia and are 1.64 billion years old. The rock record of the next 800 Million years only yields fossil molecules of primordial eukaryotes before molecular signatures of modern eukaryotes first appear in the Tonian period.
During this time, however, the Earth's atmosphere became increasingly enriched with oxygen — a metabolic product of cyanobacteria and of the first eukaryotic algae that would have been toxic to many other organisms. Later, global "Snowball Earth” glaciations occurred and the protosterol communities largely died out. The last common ancestor of all living eukaryotes may have lived 1.2 to 1.8 billion years ago. Its descendants were likely better able to survive heat and cold as well as UV radiation and displaced their primordial relatives.…the Tonian Transformation emerges as one of the most profound ecological turning points in our planet’s history. Both primordial stem groups and modern eukaryotic representatives such as red algae may have lived side by side for many hundreds of millions of years.
Christian Hallmann.
Since all stem group eukaryotes are long extinct, we will never know for certain how most of our early relatives looked like, but artistic efforts have created tentative visualisations (see pictures attached), while the primordial steroids may eventually shed more light on their biochemistry and lifestyle.
Research at ANU, MARUM and GFZ continues to pursue tracing the roots of our existence — the discovery of protosterols now brings us one step closer to understanding how our earliest ancestors lived and evolved.Earth was a microbial world for much of its history and left few traces.
Benjamin J. Nettersheim.
Title of the original study: Jochen J. Brocks, Benjamin J. Nettersheim et al.: Lost world of complex life and the late rise of the eukaryotic crown. In: Nature. DOI: 10.1038/s41586-023-06170-w
AbstractIn summary, the presence of these chemical fossils was predicted 30 years ago by a Noble Prize-winning scientist, using the Theory of Evolution. They have now been found in abundance, exactly when and where the theory predicted, and it all took place on an Earth that is many orders of magnitude older than creations claim.
Eukaryotic life appears to have flourished surprisingly late in the history of our planet. This view is based on the low diversity of diagnostic eukaryotic fossils in marine sediments of mid-Proterozoic age (around 1,600 to 800 million years ago) and an absence of steranes, the molecular fossils of eukaryotic membrane sterols1,2. This scarcity of eukaryotic remains is difficult to reconcile with molecular clocks that suggest that the last eukaryotic common ancestor (LECA) had already emerged between around 1,200 and more than 1,800 million years ago. LECA, in turn, must have been preceded by stem-group eukaryotic forms by several hundred million years3. Here we report the discovery of abundant protosteroids in sedimentary rocks of mid-Proterozoic age. These primordial compounds had previously remained unnoticed because their structures represent early intermediates of the modern sterol biosynthetic pathway, as predicted by Konrad Bloch4. The protosteroids reveal an ecologically prominent ‘protosterol biota’ that was widespread and abundant in aquatic environments from at least 1,640 to around 800 million years ago and that probably comprised ancient protosterol-producing bacteria and deep-branching stem-group eukaryotes. Modern eukaryotes started to appear in the Tonian period (1,000 to 720 million years ago), fuelled by the proliferation of red algae (rhodophytes) by around 800 million years ago. This ‘Tonian transformation’ emerges as one of the most profound ecological turning points in the Earth’s history.
Brocks, J.J., Nettersheim, B.J., Adam, P. et al.
Lost world of complex life and the late rise of the eukaryotic crown.
Nature (2023). https://doi.org/10.1038/s41586-023-06170-w
© 2023 Springer Nature Ltd.
Reprinted under the terms of s60 of the Copyright, Designs and Patents Act 1988.
In other words, yet another casual refutation of creationism by scientists who simply revealed the truth.
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