Refuting Creationism - First Steps to Abiogenesis

Diagram of the atmospheric evolution of Earth's ancient atmosphere estimated by this study

© Yoshida et al.

Research News - How Life Began on Earth: Modeling Earth's Ancient Atmosphere | Tohoku University Global Site

The fact that living organisms arose on Earth from inorganic sources rather than being made of nothing by magic, is an indisputable fact because there are living organisms on Earth and the chemicals they are composed of all exist on the planet in inorganic minerals and gases. 'Life' contains nothing that 'non-life' doesn't contain.

This much we know, but what we don't yet know and can probably never know with certainty, is precisely how and where that happen. In fact, we don't even know whether it did all start in the same place at the same time because the reason there are two different prokaryote cells - bacteria and archaea - could be because life arose on Earth not once but twice, by two different processes in two different places at two different times.

What we have though is lots of working hypotheses in the process of being validated.

What role would Earth's atmosphere have played in abiogenesis? Earth's early atmosphere was crucial in creating the right conditions for abiogenesis—the process by which life originated from non-living matter. While the exact composition of Earth’s primordial atmosphere is still debated, its unique conditions likely contributed in several essential ways:

1. Provision of Basic Building Blocks
   
   • Earth’s early atmosphere likely contained simple molecules like methane (CH₄), ammonia (NH₃), hydrogen (H₂), carbon dioxide (CO₂), nitrogen (N₂), and water vapor (H₂O). These molecules are rich in carbon, nitrogen, oxygen, and hydrogen—elements that are vital for organic compounds and, ultimately, for life.
   • When exposed to energy sources like ultraviolet (UV) radiation from the Sun or electrical discharges from lightning, these molecules could recombine into more complex organic molecules, such as amino acids and nucleotides, which are the building blocks of proteins and nucleic acids, respectively.
   
   
2. Facilitation of Prebiotic Chemistry
   
   • Experiments like the famous Miller-Urey experiment in 1953 showed that simple gases (methane, ammonia, hydrogen, and water vapor) in an atmosphere subjected to electrical sparks could produce amino acids. This suggests that Earth’s early atmosphere could have been instrumental in initiating chemical reactions that synthesized complex organic molecules.
   • Without a protective ozone layer, the early atmosphere allowed substantial UV radiation to penetrate the Earth’s surface, providing the energy necessary to drive these prebiotic reactions.
   
   
3. Supporting a Reducing Environment
   
   • The presence of reducing gases (such as methane and ammonia) would favor the formation of organic molecules because such conditions prevent the oxidation (and hence destruction) of organic compounds. Oxygen is highly reactive and can break down organic molecules, so the absence of free oxygen in the early atmosphere was likely a key factor that allowed these molecules to accumulate and react.
   • This reducing environment might have helped organic compounds to survive long enough to form stable, self-replicating systems.
   
   
4. Encouraging Geochemical Interactions
   
   • The interaction between the early atmosphere and the oceans, along with geothermal activity like volcanic eruptions and hydrothermal vents, provided a diverse range of chemical environments. In particular, hydrothermal vents may have supplied essential minerals and additional energy sources, further driving complex chemical reactions that are believed to be important in the formation of life.
   • The cycling of materials between the atmosphere and oceans would have contributed to creating localized "hotspots" for prebiotic reactions.
   
   
5. Protection and Concentration Mechanisms
   
   • The atmosphere also played a protective role by preventing the immediate dissipation of important compounds into space. It allowed the concentration of molecules and gases at Earth’s surface, increasing the chances of interactions among the essential precursors to life.
   • Early atmospheres may have helped regulate surface temperatures, preventing extreme fluctuations that would have been hostile to complex chemistry.
   
   
6. Encouraging Self-Organization and Membrane Formation
   
   • Interactions in the early atmosphere could have contributed to the formation of lipid molecules that could aggregate to form primitive cell-like structures or vesicles. These structures would eventually help in containing and protecting reactions necessary for early metabolic pathways.
   • These early "proto-cells" or vesicles would have been necessary to create a boundary for molecular interactions, which is a critical step toward the organization needed for cellular life.

In summary, Earth’s early atmosphere provided a chemically conducive, energetically rich environment that fostered the synthesis and concentration of organic molecules necessary for abiogenesis. This atmosphere also shielded these nascent molecules, allowing them to organize and evolve toward increasingly complex systems, eventually leading to the first living organisms.

One of which is the precise details of the atmosphere on the Early Earth, which is important because it would have had a major impact on the rest of the environment in which life arose. To gain a better understanding of that, a team from Tohoku University, Tokyo University and Hokkaido University, Japan, led by Tatsuya Yoshida have succeeded in modelling that atmosphere, as explained in a Tohoku University press release and published in the journal Astrobiology:

How Life Began on Earth: Modeling Earth's Ancient Atmosphere

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The key to unlocking the secrets of distant planets starts right here on Earth. Researchers at Tohoku University, the University of Tokyo, and Hokkaido University have developed a model considering various atmospheric chemical reactions to estimate how the atmosphere - and the first signs of life - evolved on Earth.

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Ancient Earth was nothing like our current home. It was a much more hostile place; rich in metallic iron with an atmosphere containing hydrogen and methane.

Shungo Koyama, co-author
Graduate School of Science
Tohoku University, Sendai, Japan.

These molecules contain an important clue to how life was initially formed. When exposed to solar ultraviolet (UV) radiation, they undergo a chemical reaction that produces organics (also known as the "building blocks of life"). Part of these organics were precursors to essential biomolecules, such as amino acids and nucleic acids. However, understanding the role of UV radiation is difficult. Firstly, this type of atmosphere is unstable and likely underwent rapid changes due to atmospheric chemical reactions. Secondly, when UV radiation efficiently breaks down water vapour in the atmosphere and forms oxidative molecules, the precise branching ratio and timescale has not been determined. In order to address these issues, a 1D photochemical model was created to make accurate predictions about what the atmosphere was like on Earth long ago.

The calculation reveals that most hydrogen was lost to space and that hydrocarbons like acetylene (produced from methane) shielded UV radiation. This inhibition of UV radiation significantly reduced the breakdown of water vapour and subsequent oxidation of methane, thus enhancing the production of organics. If the initial amount of methane was equivalent to that of the amount of carbon found on the present-day Earth's surface, organic layers several hundred metres thick could have formed.

There may have been an accumulation of organics that created what was like an enriched soup of important building blocks. That could have been the source from which living things first emerged on Earth.

Tatsuya Yoshida, lead author
Graduate School of Science
Tohoku University, Sendai, Japan.

The model suggests that the atmosphere on ancient Earth was strikingly similar to what we see on current day neighbouring planets: Venus and Mars. However, despite their proximity, Earth evolved into a completely different environment. Researchers are trying to understand what makes Earth so special. As such, this model allows us to deepen our understanding of whether atmospheric evolution and the origin of life on Earth are unique or share common patterns with other planetary systems.

These findings were published in the journal Astrobiology on October 22, 2024.

Publication Details:

Tatsuya Yoshida, Shungo Koyama, Yuki Nakamura, Naoki Terada and Kiyoshi Kuramoto
Self-Shielding Enhanced Organics Synthesis in an Early Reduced Earth's Atmosphere Astrobiology DOI: 10.1089/ast.2024.0048

Abstract
Earth is expected to have acquired a reduced proto-atmosphere enriched in H₂ and CH₄ through the accretion of building blocks that contain metallic Fe and/or the gravitational trapping of surrounding nebula gas. Such an early, wet, reduced atmosphere that covers a proto-ocean would then ultimately evolve toward oxidized chemical compositions through photochemical processes that involve reactions with H₂O-derived oxidant radicals and the selective escape of hydrogen to space. During this time, atmospheric CH₄ could be photochemically reprocessed to generate not only C-bearing oxides but also organics. However, the branching ratio between organic matter formation and oxidation remains unknown despite its significance on the abiotic chemical evolution of early Earth. Here, we show via numerical analyses that UV absorptions by gaseous hydrocarbons such as C₂H₂ and C₃H₄ significantly suppress H₂O photolysis and subsequent CH₄ oxidation during the photochemical evolution of a wet proto-atmosphere enriched in H₂ and CH₄. As a result, nearly half of the initial CH₄ converted to heavier organics along with the deposition of prebiotically essential molecules such as HCN and H₂CO on the surface of a primordial ocean for a geological timescale order of 10–100 Myr. Our results suggest that the accumulation of organics and prebiotically important molecules in the proto-ocean could produce a soup enriched in various organics, which might have eventually led to the emergence of living organisms.

Yoshida, Tatsuya; Koyama, Shungo; Nakamura, Yuki; Terada, Naoki; Kuramoto, Kiyoshi
Self-Shielding Enhanced Organics Synthesis in an Early Reduced Earth’s Atmosphere Journal of Astrobiology (2024) DOI: 10.1089/ast.2024.0048

© 2024 Mary Ann Liebert, Inc.
Reprinted under the terms of s60 of the Copyright, Designs and Patents Act 1988.

So, by the action if UV radiation from the sun on the inorganic molecules in Earth's early atmosphere for a period of some 10-100 million years, the oceans could have accumulated the basic building blocks for organic organisms to get started, and all th result of chemistry and physics with no magic gods involved at any point.

And, as usual with scientific discoveries, the truth is shown to have little resemblance to the origin myths the parochial Bronze Age pastoralists made up to fill the yawning chasm in their knowledge and understanding of the world around them, with their belief that Earth had only existed for a few thousand years, so were blissfully ignorant of the 99.9975% of its history that occurred before then.

Creationism Refuted - What a Mallorcan Cave Tells Us Of Events Before 'Creation Week'.

Bogdan Onac studies the phreatic overgrowths seen in this photo. They grow exactly at sea level and offer a more accurate reconstruction of past sea level history. He used these to determine the age of the submerged bridge.

Photo: M.À. Perelló

Close-up view of the submerged stone bridge from Genovesa Cave, Mallorca, Spain

Photo: R. Landreth

What a submerged ancient bridge discovered in a Spanish cave reveals about early human settlement

The Spanish Balearic Island of Mallorca (Majorca), a favourite holiday destination for Brits looking for sun, sea and sand, is composed largely of limestone which lends itself to cave formation and limestone caves lend themselves to stalactite formation.

They also provided shelters for early humans, so the evidence of human presence gives us a good picture of the timing of human migration into the area.

Like 99,9975% of Earth's history, the events recorded in these Mallorcan caves happened in the long pre-'Creation Week' history, long before creationists believe Earth was made out of nothing by magic.

Readers may recall my recent blog post concerning what is known of the changes in biodiversity as the Mediterranean dried up, then flooded again about 5.5 million years ago due to plate tectonic movements. These Mallorcan caves formed after those catastrophic events but still well before creationism's 'Creation Week'.

The stalactites in one cave in particular, the Genovesa Cave at the eastern end of the island hold a record of sea-level changes that correlate with known periods of glaciation and interglacial warmer periods. During periods of glaciation, water was locked up in polar ice and glaciers, so sea-levels fell.

What information do you have on the Genovesa Cave in Mallorca, Spain, and what it tells us of sea-level changes? Genovesa Cave, located on the eastern coast of Mallorca, Spain, is a notable site for studying past sea-level changes due to its unique speleothem formations (such as stalactites and stalagmites) and its position relative to current sea levels.

Key Information About Genovesa Cave

1. Geological Context:
   • Genovesa Cave is a partially submerged cave system found on the island of Mallorca, part of the Balearic Islands in the western Mediterranean Sea.
   • The cave has been naturally formed in limestone rock, a type of carbonate rock that is particularly responsive to changes in sea level.
   
   
2. Evidence of Past Sea-Level Changes:
   • Speleothem Growth Stages: The most significant evidence for past sea-level changes comes from speleothems, which are mineral deposits formed in caves by the precipitation of carbonate minerals from dripping water. When sea levels rise, the cave becomes submerged, and speleothem growth ceases due to a lack of contact with air. When sea levels fall, the cave is re-exposed to air, allowing speleothems to grow again.
   • Dating Techniques: Researchers use uranium-thorium (U-Th) dating methods to date these speleothems accurately. The growth and cessation periods can be correlated with known global sea-level fluctuations, such as those associated with glacial and interglacial cycles during the Quaternary period (the last 2.6 million years).
   
   
3. Sea-Level Highstands and Lowstands:
   
   
   • Studies of Genovesa Cave have identified speleothems that formed during several past interglacial periods when sea levels were higher than today. This provides evidence for higher sea levels during warm periods such as the Last Interglacial (about 125,000 years ago).
   • Conversely, periods when the cave was submerged or when speleothem growth was halted correspond to glacial periods when sea levels were much lower, sometimes up to 120 meters lower than the current level.

Implications for Understanding Sea-Level Changes

1. Local and Global Sea-Level Correlation:
   • The data obtained from Genovesa Cave speleothems align well with global records of sea-level changes, such as those derived from coral reefs and marine terraces. This reinforces the idea that the cave provides a reliable local record that reflects broader, global sea-level trends.
   
   
2. Understanding the Mediterranean Sea's Response:
   • The cave's findings contribute to our understanding of how the Mediterranean Sea responded to global climatic events. During periods of rapid deglaciation, for example, meltwater pulses could have caused rapid sea-level rises, which would be recorded in the cave's geological formations.
   
   
3. Insights into Future Sea-Level Rise:
   • Studying past sea levels helps scientists predict future changes, particularly in the context of global warming and potential ice sheet melting. The high-resolution records from Genovesa Cave can help refine models of future sea-level rise, especially in understanding how fast and how much sea levels could change.

In Summary

Genovesa Cave in Mallorca is a critical natural archive for studying past sea-level changes, providing both a local record of changes in the Mediterranean and contributing to the understanding of global sea-level fluctuations. The cave's speleothem formations, when dated, tell us about the timing and extent of past sea levels, helping us predict future changes.

Did the cave exist during the Messinian Salinity Crisis and the following Zanclean flood?

Genovesa Cave, like many other karstic cave systems on Mallorca, likely did not exist in its current form during the Messinian Salinity Crisis (MSC) and the subsequent Zanclean flood. However, understanding its formation requires a bit of geological context about these events and the development of the cave.

Geological Context of the Messinian Salinity Crisis and Zanclean Flood

1. Messinian Salinity Crisis (MSC) (5.96 to 5.33 million years ago):
   • The MSC was a period when the Mediterranean Sea was largely cut off from the Atlantic Ocean due to tectonic movements, leading to extreme evaporation and a significant drop in sea level. During this time, the Mediterranean became partially or fully desiccated, creating vast salt deposits and deep erosional features (like canyons and river systems) that extended below the current sea level.
   • Sea levels were drastically lower, estimated to have dropped by as much as 1,500 meters. The drop exposed large portions of the continental shelf and caused significant erosion of the landscape, including the areas around Mallorca.
   
   
2. Zanclean Flood (5.33 million years ago):
   • The Zanclean flood marked the end of the MSC, when the Strait of Gibraltar reopened, and Atlantic waters rapidly refilled the Mediterranean basin. This event is thought to have raised sea levels in the Mediterranean by up to 1,500 meters over a short period, flooding the previously exposed and desiccated areas.

Did Genovesa Cave Exist During These Events?

1. Formation of Genovesa Cave:
   • Genovesa Cave, like many karst caves, formed much later than the Messinian Salinity Crisis and the Zanclean flood. The formation of such caves typically occurs over long periods through the dissolution of limestone by slightly acidic groundwater. This process, known as karstification, is generally linked to periods when the sea level is relatively stable and when the water table is at an appropriate level to facilitate cave development.
   • Given that the MSC was a period of extreme environmental conditions (both in terms of erosion during the desiccation and rapid flooding during the Zanclean flood), the specific geological setting that would allow for the gradual formation of karstic caves like Genovesa likely did not exist until after these events.
   
   
2. Post-MSC Karst Development:
   • After the Mediterranean was refilled and the sea level stabilized following the Zanclean flood, conditions would have been more suitable for the formation of karst systems like Genovesa Cave. The Quaternary period, which began about 2.6 million years ago, saw multiple cycles of glacial and interglacial periods, during which fluctuations in sea levels, combined with periods of stability, promoted the development of karst caves in the limestone regions of Mallorca.
   
   
3. Timing of Cave Formation:
   • The specific timing of the formation of Genovesa Cave is not precisely known, but it is generally accepted that most of the karst caves in Mallorca formed during the Pleistocene epoch (2.6 million to 11,700 years ago) or even more recently. The cave's features and deposits suggest that it has undergone several phases of exposure and submersion due to sea-level changes throughout this period, well after the MSC and Zanclean flood.

Conclusion

Genovesa Cave, in its current form, did not exist during the Messinian Salinity Crisis or the subsequent Zanclean flood. The cave likely formed much later, during the Quaternary period, as conditions became suitable for karstification following the stabilization of Mediterranean sea levels after these dramatic geological events. The MSC and the Zanclean flood were important in shaping the broader landscape of the Mediterranean region, but the specific conditions necessary for the formation of caves like Genovesa developed much later.

What are phreatic overgrowths on Speleothems (POS)?

Phreatic overgrowths on speleothems (POS) are unique mineral deposits that form in coastal cave environments at the interface between freshwater and seawater. These overgrowths are specifically associated with periods when the cave is partially submerged in a mix of fresh and saline water, typically at or near sea level. They provide important clues about past sea-level positions and climate conditions.

Key Characteristics of Phreatic Overgrowths on Speleothems

1. Definition:
   • Phreatic overgrowths on speleothems are secondary carbonate deposits, typically composed of minerals like calcite or aragonite. They form on existing speleothems (such as stalactites, stalagmites, or flowstones) when the cave environment is inundated by a fluctuating water table that is influenced by sea level.
2. Formation Environment:
   • These overgrowths develop in the "phreatic zone" of caves— the zone that is below the water table and is saturated with water. In coastal caves, this zone is directly affected by sea-level changes. When sea level is stable or fluctuates within a certain range, the mixing zone between freshwater and saline water can lead to mineral precipitation on submerged speleothems.
3. Mechanism of Formation:
   • Phreatic overgrowths form due to a process known as "degassing" or "precipitation" when carbon dioxide (CO₂) dissolved in water escapes into the cave air. This loss of CO₂ from water that is saturated with calcium carbonate (CaCO₃) promotes the deposition of calcite or aragonite on existing cave formations.
   • In coastal caves, the mixing of fresh and saltwater enhances this process. Freshwater entering the cave mixes with seawater, creating conditions where minerals precipitate more readily due to changes in water chemistry, such as shifts in pH, temperature, and CO₂ concentration.
4. Morphology and Appearance:
   • Phreatic overgrowths typically form flat or gently sloping horizontal crusts, rims, or coatings on existing cave formations. Their horizontal nature reflects the stable water table level at which they formed.
   • These deposits can vary in thickness and are often found at multiple levels within the cave, corresponding to different sea levels over time.

Importance of Phreatic Overgrowths on Speleothems

1. Indicators of Past Sea Levels:
   • POS are valuable indicators of past sea levels because they form at specific elevations related to the water table, which in coastal environments is closely linked to sea level. By dating these formations using techniques such as uranium-thorium (U-Th) dating, scientists can reconstruct past sea-level positions and determine the timing and magnitude of sea-level changes over thousands to hundreds of thousands of years.
2. Understanding Paleoclimatic Conditions:
   • Beyond sea levels, POS can provide insights into broader paleoclimatic conditions. The chemical composition of these overgrowths (e.g., stable isotopes of oxygen and carbon) can offer information about past temperature, rainfall patterns, and even water source characteristics.
3. Calibrating Sea-Level Rise Models:
   • The precise dating of phreatic overgrowths helps in calibrating models of sea-level rise, particularly when cross-referenced with other geological and paleoclimatic data, such as coral reefs, marine terraces, and ice cores. This is particularly important for understanding the rate of sea-level rise in response to past climate events, such as glacial and interglacial periods.

Examples of POS Studies

• Mediterranean Caves (Mallorca, Spain): In Mallorca, POS have been extensively studied in caves like Genovesa Cave and others along the coast. These formations have been used to map out the history of Mediterranean sea-level changes over the last several hundred thousand years, including periods such as the Last Interglacial (about 125,000 years ago).
• Caribbean and Other Coastal Regions: Similar studies have been conducted in coastal caves in the Caribbean and other regions, where POS help reconstruct sea-level fluctuations and regional climate changes.

Summary

Phreatic overgrowths on speleothems are carbonate deposits formed in caves at the interface between freshwater and seawater, directly reflecting past sea levels. They serve as crucial archives for understanding past sea-level changes, climate conditions, and the complex interplay between global climate and regional environmental changes.

In the context of dating caves, what does the following mean?

'A ²³²Th/²³⁸U-²³⁴U/²³⁸U-²³⁰Th/²³⁸U (plotted as a Rosholt A type) isochron age of 5479 ± 120 years B.P.'

The phrase describes the result of a specific type of uranium-thorium dating method used to determine the age of materials, such as carbonate deposits in caves. Let's break down what each part of this phrase means:

Uranium-Thorium (U-Th) Dating Overview

Uranium-Thorium (U-Th) dating also known as Thorium-230 dating is a radiometric dating technique used to determine the age of calcium carbonate materials like speleothems (stalactites, stalagmites, and other cave formations). The method relies on the radioactive decay of uranium isotopes to thorium isotopes. Here's a breakdown of the isotopes involved:

• ²³⁸U (Uranium-238): The parent isotope, which decays over time into various intermediate daughter isotopes, including ²³⁴U (Uranium-234) and ²³⁰Th (Thorium-230).
• ²³²Th (Thorium-232): A stable, non-radioactive isotope of thorium that is not involved in the decay chain but can be present in the sample as a contaminant or from initial conditions.

Explanation of the Phrase

1. "²³²Th/²³⁸U-²³⁴U/²³⁸U-²³⁰Th/²³⁸U":
   • These ratios represent the proportions of different isotopes present in the sample.
     • ²³²Th/²³⁸U: Indicates the ratio of thorium-232 to uranium-238 in the sample.
     • ²³⁴U/²³⁸U: Indicates the ratio of uranium-234 (an intermediate decay product) to uranium-238.
     • ²³⁰Th/²³⁸U: Indicates the ratio of thorium-230 (the target daughter isotope) to uranium-238.
   
   
2. "Plotted as a Rosholt A type isochron":
   • An isochron is a graphical method used to determine the age of a sample by plotting the ratios of isotopes against each other. The slope of the line (the isochron) represents the time that has passed since the sample's formation.
   • "Rosholt A type" refers to a specific type of isochron plot developed by John Rosholt, which plots the ratios of these isotopes in a way that accounts for initial thorium contamination (²³²Th). This method provides a more accurate age by correcting for the presence of any initial, non-radiogenic thorium in the sample.
   
   
3. "Isochron age of 5479 ± 120 years B.P.":
   • This is the calculated age of the sample, determined by the U-Th dating method using the isochron plot.
   • 5479 years B.P.: This means "5479 years Before Present," where "Before Present" is typically defined as before the year 1950. The sample is estimated to have formed 5479 years ago.
   • ± 120 years: This represents the margin of error or uncertainty in the dating. The true age is likely within the range of 5479 years plus or minus 120 years (i.e., between 5359 and 5599 years ago).

Summary

The phrase refers to a method of dating a cave sample using uranium-thorium dating and an isochron plot (Rosholt A type) to determine that the sample is approximately 5479 years old, with an uncertainty of ±120 years. The use of multiple isotope ratios and the isochron method helps correct for initial contamination and provides a more accurate age estimate.

This allowed stalactites to grow as water containing dissolved minerals seeped through the cave roof and dripped down, evaporating as it did so, and leaving a record of rainfall. During interglacial period, sea-levels rose, submerging the caves and preventing the growth of stalactites, leaving a record of these sea-level rises.

But, apart from these records of climate and sea-level changes, the Genovesa Cave contains a more tangible record - that of human habitation on the island and so of colonisation of the Western Mediterranean and the Iberian peninsula in particular.

It is a submerged stone bridge, built when the sea-levels were lower at the height of the last ice age. The bridge was used to cross a now submerged small lake at a low point in the cave system and must have been deliberately constructed.

Scientists these days rarely, if ever, set out to refute creationist mythology but all do so incidentally, simply by doing what good science does and discovering the facts, and this discovery, by speleogeologists from the University of South Florida, does just that. It is the subject of a recent open access paper in Communications Earth & Environment and a recent news release from the University of South Florida:

What a submerged ancient bridge discovered in a Spanish cave reveals about early human settlement

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A new study led by the University of South Florida has shed light on the human colonization of the western Mediterranean, revealing that humans settled there much earlier than previously believed. This research, detailed in a recent issue of the journal, Communications Earth & Environment, challenges long-held assumptions and narrows the gap between the settlement timelines of islands throughout the Mediterranean region.

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Reconstructing early human colonization on Mediterranean islands is challenging due to limited archaeological evidence. By studying a 25-foot submerged bridge, an interdisciplinary research team – led by USF geology Professor Bogdan Onac – was able to provide compelling evidence of earlier human activity inside Genovesa Cave, located in the Spanish island of Mallorca.

The presence of this submerged bridge and other artifacts indicates a sophisticated level of activity, implying that early settlers recognized the cave's water resources and strategically built infrastructure to navigate it.

Professor Bogdan P. Onac, Lead author
Karst Research Group
School of Geosciences
University of South Florida, Tampa, FL, USA.

The cave, located near Mallorca’s coast, has passages now flooded due to rising sea levels, with distinct calcite encrustations forming during periods of high sea level. These formations, along with a light-colored band on the submerged bridge, serve as proxies for precisely tracking historical sea-level changes and dating the bridge's construction.

Mallorca, despite being the sixth largest island in the Mediterranean, was among the last to be colonized. Previous research suggested human presence as far back as 9,000 years, but inconsistencies and poor preservation of the radiocarbon dated material, such as nearby bones and pottery, led to doubts about these findings. Newer studies have used charcoal, ash and bones found on the island to create a timeline of human settlement about 4,400 years ago. This aligns the timeline of human presence with significant environmental events, such as the extinction of the goat-antelope genus Myotragus balearicus.

By analyzing overgrowths of minerals on the bridge and the elevation of a coloration band on the bridge, Onac and the team discovered the bridge was constructed nearly 6,000 years ago, more than two-thousand years older than the previous estimation – narrowing the timeline gap between eastern and western Mediterranean settlements.

This research underscores the importance of interdisciplinary collaboration in uncovering historical truths and advancing our understanding of human history.

Professor Bogdan P. Onac.

This study was supported by several National Science Foundation grants and involved extensive fieldwork, including underwater exploration and precise dating techniques. Onac will continue exploring cave systems, some of which have deposits that formed millions of years ago, so he can identify preindustrial sea levels and examine the impact of modern greenhouse warming on sea-level rise.

This research was done in collaboration with Harvard University, the University of New Mexico and the University of Balearic Islands.

Abstract
Reconstructing early human colonization of the Balearic Islands in the western Mediterranean is challenging due to limited archaeological evidence. Current understanding places human arrival ~4400 years ago. Here, U-series data from phreatic overgrowth on speleothems are combined with the discovery of a submerged bridge in Genovesa Cave that exhibits a distinctive coloration band near its top. The band is at the same depth as the phreatic overgrowth on speleothems (−1.1 meters), both of which indicate a sea-level stillstand between ~6000 and ~5400 years ago. Integrating the bridge depth with a high-resolution Holocene sea-level curve for Mallorca and the dated phreatic overgrowth on speleothems level constrains the construction of the bridge between ~6000 and ~5600 years ago. Subsequent sea-level rise flooded the archeological structure, ruling out later construction dates. This provides evidence for early human presence on the island dating at least 5600 and possibly beyond ~6000 years ago.

Introduction
Mallorca, the main island of the Balearic Archipelago, is the sixth largest in the Mediterranean Sea, yet it was among the last to be colonized¹. An in-depth discussion concerning the earliest colonization of various Mediterranean islands, including Mallorca, may be found in Cherry and Leppard1, Dawson², and Simmons³. Despite extensive research on this topic, there has been considerable disagreement about the timing of the earliest colonization of Mallorca. Radiocarbon dating of bone material excavated from Cova (Cave) de Moleta indicate human presence on the island as early as 7000 calibrated years before present (cal B.P.)⁴. Subsequent age determinations from findings in Cova de Canet, further extended the timeline, suggesting human occupation dating back to approximately 9000 cal B.P.⁵. A series of publications^{6,7,8,9,10,11} revealed inconsistencies regarding the exact stratigraphic position and context of the dated bone (sample KBN-640d12) in Cova de Moleta. Due to the overall poor preservation of the samples and the lack of clear and specific information on this particular radiocarbon-dated sample, Ramis and Alcover⁷ suggested that the bone fragment, initially identified as human, might actually belong to M. balearicus, an endemic bovid. Consequently, this sample was considered not relevant for determining the timing of the island’s colonization. Similarly, the radiocarbon dates from Cova de Canet were considered highly controversial because they originate from a charcoal layer that lacks clear evidence of human activity^7,8. Furthermore, in neither of these caves do the M. balearicus bones show butchery marks, making it difficult to establish a clear link to contemporary human presence2. Due to the aforementioned issues these early results were deemed unreliable^1,8,13.

Several studies have reevaluated most of the previously dated materials and supplemented them with new radiocarbon dates obtained from charcoal, ash, and bones^6,7,9,10. Based on these new results, there is now a consensus that the timeframe for earliest human settlement on the island is between 4600 and 4200 cal B.P.¹⁴.

Dawson2 presents a synthesis of the various lines of argument regarding arrival models in the Balearic islands that includes: (1) Early (~9000 cal B.P.), (2) Intermediate (~7600 cal B.P.), and (3) Late (~5000 cal B.P.) arrival phases. The last two models suggest the existence of stable settlements, yet only the third one has been deemed plausible in the local archeological literature^7,8,14.

While there has been a growing body of evidence revealing progressively earlier human settlements on many islands in the Mediterranean basin, the timeline for the initial human colonization in Mallorca has seen relatively minor adjustments over the past decades^8,15,16. The latest research suggests that this colonization occurred approximately 4400 cal B.P., coinciding with the human-mediated extinction of Myotragus balearicus¹⁴. This conclusion is based on two radiocarbon ages, which provide a relatively narrow time window of 350 years (p > 90%) between the last documented Myotragus bone (4581–4417 cal B.P.) and the first dated sheep bone (4417–4231 cal B.P.). However, it remains challenging to confirm whether the ages of these paleontological remains represent the latest or the earliest such occurrences on the island. Subsequent field work may shed light on this matter.

Our study site is a submerged archeological structure in the Genovesa Cave (also known as Cova de’n Bessó; 39°31’32” N, 3°19’2” E), situated in the eastern part of Mallorca (Fig. 1a, b). The cave hosts ceramic sherds and stone constructions. The latter includes a stone-paved path that connects the cave entrance to the first underground lake (Fig. 1d), a cyclopean stone wall running parallel to the path, and an 8.62 m long¹⁷ and 0.5 m high stone walkway (hereafter referred as to bridge) oriented NE–SW (Fig. 1c, e, Supplementary Fig. 1, Supplementary Table 1). This last structure was built across a lake by stacking large limestone breakdown blocks on top of each other, without the use of mortar or cement. The uppermost layer comprises flat boulders of considerable size (Supplementary Fig. 1b). The largest stone measures 1.63 m in length and 0.6 m in width. Relative to the preindustrial (pre-1900 CE) sea level, the bridge is submerged by 1.05 ± 0.1 m of water at its upper part (Figs. 1e, 2). However, at the time of its construction, it served as an access path to the only other dry chamber in the cave (Sala de les Rates-pinyades, i.e., Bats Room), where pottery, tentatively attributed to the Naviform period (ca. 3550–3000 cal B.P.) was discovered^18,19. The bridge structure was inferred to have been built around the same period²⁰.

Fig. 1: Cave and sample locations.

a Map showing Mallorca in the western Mediterranean (black square). b Location of Genovesa and Drac caves; CCG: Closos de Can Gaià archeological site. c Plan of Genovesa Cave showing the location of the phreatic overgrowth on speleothems samples (yellow circles) and the survey station (red dot). d Photograph of the stone-paved path leading to the bridge (person height = 167 cm). e Cross-section (x–x’) indicating the location of the submerged bridge relative to the cave entrance and the present sea level. Maps (a, b) are available under CC Public Domain License from https://pixabay.com/illustrations/map-europe-world-earth-continent-2672639/ and https://pixabay.com/illustrations/mallorca-map-land-country-europe-968363/, respectively.

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Fig. 2: Positional relationship between the bridge, preindustrial sea level, and analyzed samples.

The cross sections depict the spatial relationship between the submerged bridge and the U-series dated samples (phreatic overgrowth on speleothems: orange/yellow spindle; soda straw tips: red circle) from Genovesa and Drac caves. The vertical scale applies uniformly to all samples from both caves. All ages are reported as thousands of years (kyr) before present, where present is defined as 1950 CE.

Here, we integrate uranium-series (U-series) age data acquired from phreatic overgrowth on speleothems and stalactite tips in Genovesa and Drac caves, along with Late Holocene relative sea level (RSL) information available for Mallorca²¹. Additionally, we consider the presence of the bridge, the coloration mark on its upper part, and the depths at which these respective features occur. This combined evidence contributes valuable insights to the ongoing debate surrounding the timing of human colonization on Mallorca.

Because Creationists love to find fault with the geochronology in these records of pre-'Creation Week' events, I've included sections on geochronology here:

Results and discussion
Speleothems and sea level
Proxies for cave-based sea-level reconstructions include mineralogical (sediments, speleothems)^22,23, archeological (fish tanks, saltpans, submerged structures, etc.)²⁴, and biological (borings, worm tubes, etc.)²⁴ records. In the case of Genovesa Cave, a typical coastal karst feature situated <450 m from the shoreline, both mineralogical and archeological records are present. Many of its well-decorated passages, galleries, and chambers are now flooded due to rising sea levels²⁰. Because of the cave’s proximity to the coast and the high permeability of the Upper Miocene host rock²⁵, the hydraulic gradient is negligible (9 × 10^-5 m /m) for such short distances (see Methods), and thus the water table in the cave is, and was in the past, coincident with sea ^26,27. During times of high sea level stillstands, when the cave was partly flooded, distinct encrustations of calcite and aragonite accumulated over preexisting stalactites, forming the so-called phreatic overgrowths on speleothems²⁸ (POS). This is a particularly useful proxy for precisely and accurately reconstructing sea-level changes across various timescales^21,29. Furthermore, ordinary stalactites, which form in cave passages above the water table and later become submerged as sea-levels rise are also valuable in this process since they document the moment when the cave shifted from being air- to water-filled²².

A distinct light-colored band (~15 cm wide) is visible along the entire bridge at its upper part (Fig. 2, Supplementary Fig. 1a). This coloration mark bears a resemblance to a “bathtub ring” and its presence is likely related to a relatively short-lived stable water table that allowed the precipitation of a sub-millimeter calcite crust at the water/air interface. When the water level increased, the calcite did not disappear since the water below the water table remained somewhat saturated with respect to calcium carbonate. As discussed later, this feature along with the new POS ages and their elevation play a crucial role in determining when this bridge, now submerged, was constructed.

Geochronology
The U-series ages (n = 34; 28 for POS and 6 from stalactites) are given in Supplementary Table 2 and are all reported as years before present (BP), where present is 1950 CE. Ten of these ages are from POS samples GE-D8 (Genovesa Cave; Supplementary Fig. 2) and DR-D15 dated as part of a prior study²¹. The latter was collected in Drac Cave (39°32’9” N, 3°19’49” E), located 1.6 km to the north-east of Genovesa Cave (Fig. 1c, Supplementary Figs. S3–S4).

Regardless of the sampling depth, all the vadose stalactites on which the POS formed in both caves, produced ages older than 8200 years B.P. (Fig. 2, Supplementary Fig. 5). The phreatic overgrowth samples GE-D6, GE-D7, and DR-D23 (Supplementary Figs. S6–S8), precipitated at ~1.10 ± 0.1 m below the preindustrial sea level (mbpsl). A ²³²Th/²³⁸U-²³⁴U/²³⁸U-²³⁰Th/²³⁸U (plotted as a Rosholt A type) isochron age of 5479 ± 120 years B.P. (n = 3 of 4; hereafter, ± refers to 2 σ uncertainty) was measured for GE-D6 (Supplemental Table 2, Supplementary Fig. 9a). GE-D7, in the same room and at the same elevation as GE-D6, yielded a weighted average age of 5510 ± 549 years B.P. using the same correction (initial ²³⁰Th/²³²Th atomic ratio = 5.1 ± 0.4 ppm) generated by the GE-D6 isochron age. Onac et al.²¹. used a slightly higher initial for GE-D8 (8 ppm) that was located at a higher elevation than GE-D6 & -D7. For DR-D23, we obtained a ²³²Th/²³⁸U-²³⁴U/²³⁸U-²³⁰Th/²³⁸U (plotted as a Rosholt A type) isochron age of 5824 ± 140 years B.P. (n = 6) (Supplementary Table 2, Supplementary Fig. 9b). This isochron shows an exceptionally high initial ²³⁰Th/²³²Th atomic ratio = 527.5 ± 22.1 ppm, more than 10x higher than used for DR-D15 (44 ppm) from the same cave but at a different elevation²¹. The fluffy fibrous cotton-candy texture of the two sub-samples with high U component of DR-D23 may have something to do with the high initial ²³⁰Th/²³²Th. The isochron ages were necessary to produce accurate ages with smaller uncertainties.

Collectively, the POS data from Genovesa and the nearby Drac, reveal three distinct periods of relative sea-level stability (Fig. 2). One occurred at 0 ± 0.04 m from 2720 ± 11 to 296 ± 18 years B.P. The second period lasting from 3703 ± 14 to 3368 ± 8 years B.P., corresponds to a sea level of 0.25 mbpsl. Lastly, a third period at ~1.1 ± 0.1 mbpsl is documented between 5820 ± 140 and 5479 ± 120 years B.P. (Figs. 2, 3). By adding the uncertainty to the older age and subtracting the uncertainty from the younger age, the maximum time span of POS growth at 1.1 mbpsl ranges from 5964 – 5359 years B.P. During this interval, both the POS and the coloration mark formed. For the latter to develop, the bridge must have been submerged, at least to its upper surface, allowing calcite to precipitate during the sea-level stillstand. Therefore, this period is of particular interest because it may aid in providing the timeline of the bridge construction as detailed below.

Timing of bridge construction
The assembly date of the bridge in Genovesa Cave remains uncertain due to the absence of written records or a robust time-stratigraphic context. In order to constrain the building time of this archeological structure, we rely on a well-defined Late Holocene sea-level curve generated by Onac et al.²¹. for Mallorca (depicted by the solid blue line in Fig. 3) and the ages and depths at which POS grew and coloration mark formed. First, we assess previous assumptions regarding the timing of the submerged bridge construction using this curve. Then, we examine our new sea-level data in conjunction with the timing of the earliest human arrival model proposed by Bover et al.¹⁴.

The prehistoric pottery discovered in Sala de les Rates-pinyades of the Genovesa Cave has been linked to the Naviform period (3550–3000 cal B.P.). This attribution is based on typological similarities between the ceramics found in Genovesa and those documented at the Closos de Can Gaià, a Bronze Age site located ~10 km south of our cave (Fig. 1b). The archeological horizon in which comparable pottery was discovered at the latter site was dated to ~3600 cal B.P30. However, Costa and Guerrero31 argue that Closos de Can Gaià excavation required a reassessment of the chronological framework, due to issues with the radiocarbon dates. Despite this, adopting the previously reported radiocarbon age, Gràcia et al.²⁰ suggested that the construction of the bridge likely occurred toward the end of the Naviform period.

However, the RSL curve (Fig. 3) indicates that sea level was ~0.25 ± 0.1 m below the preindustrial baseline ~3500 years ago²¹, implying a total water depth of ~1.3 m in the cave lake. The vertical height of the bridge is 0.5 m, and thus it was submerged by 0.8 m of water at this time (Fig. 3). The construction of the bridge around 4400 years ago, the time suggested by Bover et al.¹⁴ to be the earliest evidence of human presence on the island, is also improbable. At that time, relative sea level in Mallorca was ~0.35 ± 0.1 m below preindustrial level, and the bridge would have been submerged by 0.7 m. Building a bridge below water level is a highly unlikely scenario, and thus it was likely built at an earlier time, when sea level was lower. The predicted relative sea-level curve for Mallorca (Fig. 3) indicates that the top of the bridge would have been close to water level no earlier than 5600 years ago and this provides an approximate lower bound on the age of the feature. The distinct coloration mark on the bridge also provides strong evidence of an age greater than the ages estimated by Gràcia et al.²⁰ and Bover et al.¹⁴. As discussed earlier and according to the POS-based relative sea-level record, this mark would not have developed if the top of the bridge was well below the water level, i.e., at times more recent than ~5500 years ago. However, an age older than 6000 years for the feature can be ruled out since sea level was even lower (Fig. 3), and the construction of a bridge at its current height would have been unnecessary.

Fig. 3: Proposed timing for bridge construction.

Comparison between the position of the submerged bridge, phreatic overgrowth on speleothems (POS), coloration mark, and the RSL prediction (blue curve)²¹ based on a Glacial Isostatic Adjustment model that uses the ICE-6G (VM 5) ice history with an upper mantle viscosity of 1.3 × 1020 Pa s. Solid symbols with age and depth uncertainties represent POS elevations. The brown rectangle depicts the bridge with its coloration band in the upper part. The insets show an underwater image of the bridge (Photo courtesy of R. Landreth) and a close-up view on the RSL position of samples GE-D6, GE-D7, and DR-D23 that grew at 1.1 mbpsl. The uncertainties for GE-D6, GE-D7, and DR-D23 are absolute 2 σ error bars based on three dimensional isochron ages or weighted average (GE-D7). The dotted blue line is a sea-level rise scenario that includes the brief stillstand inferred from the POS growth.

The phreatic overgrowths GE-D6, GE-D7, and DR-D23 from Genovesa and Drac caves formed at a relative sea level of 1.1 mbpsl, which is 5 cm below the upper part of the bridge. The two more precise isochron ages suggest sea-level remained relatively constant for a few hundreds of years between ~5964 and 5359 years B.P. The relative brevity of this time frame might explain why the morphology and size of the POS are somehow atypical and smaller compared to those POS that developed when the sea level was stable at 0 m for over 2000 years. Furthermore, this <600 year period of nearly constant sea level was sufficient to develop the coloration mark. Given that the occurrence of this feature correlates directly with the previously mentioned sea-level stillstand position, it suggests that the bridge was already in place. In fact, its construction could have commenced as early as ~6000 years ago when the water depth in the lake was ~0.25 m. However, it had to be completed before ~5600 years ago when the sea-level rose to the top surface of the bridge.

Onac, B.P., Polyak, V.J., Mitrovica, J.X. et al.
Submerged bridge constructed at least 5600 years ago indicates early human arrival in Mallorca, Spain. Commun Earth Environ 5, 457 (2024). https://doi.org/10.1038/s43247-024-01584-4

Copyright: © 2024 The authors.
Published by Springer Nature Ltd. Open access.
Reprinted under a Creative Commons Attribution 4.0 International license (CC BY 4.0)

Lots of stuff for creationists to lie about there. Firstly, there is the record of sea-level changes reflecting the advance and retreat of ice sheets over the past few tens of thousands of years.

Then there is the record of human habitation and construction of the bridge when creationist mythology says the world was subject to a genocidal flood in which all life was extinguished save a small handful of survivors that then repopulated the planet in just a few thousand years.

What a creationist now needs to do is explain why all the dating methods, which converge on these dates, are all wrong and should be converging on a much more recent date compatible with creation of Earth from nothing just 10,000 years ago and all human life originating from 8 related individuals just 4,000 years ago.

Sadly, because the authors of these myths knew nothing of the real history of the Western Mediterranean, the book they wrote, and which creationists think is a real history book, is entirely silent on the matter.

Refuting Creationism - The Fossil Record Shows Climate Change - 59-51 Million Years Before 'Creation Week'

Microscopic fossil foraminifera shells

This article is best read on a laptop, desktop or tablet

What microscopic fossilized shells tell us about ancient climate change – @theU

The bad news for creationists continues unabated as science discovers more facts, as we would expect of a counter-factual superstition.

This time it's news that new research led by University of Utah geoscientists has shown how there is a record of climate change in the fossil record in the form of traces of boron isotopes in the fossilised shells of microscopic foraminifera.

The record, 59-51 million years before creationists think Earth was created, is just another record of events in that 99.9975% of Earth's history that creationists try to shoe-horn into 10,000 to make it seem like their childish creation myth has some merit.

The record of change itself depends not on radioactive decay rates but on the ratios of stable isotopes of boron that get incorporated in the shells of microscopic foraminifera during their growth and then remain locked up as their bodies fossilise in marine sediment.

Dating of this marine sediment is done using several strands of evidence, one of which is U-Pb dating of zircon crystals, and all of which converge on the same dates (see the AI panel on the right).
What changes is the ratio of ¹¹B (δ¹¹B) incorporated in the shells of foraminifera during their lifetime, and this is related to the pH of the seawater. pH of sea water is in turn determined by the level of atmospheric CO₂ - the higher the level of CO₂, the lower the pH due to dissolved carbonic acid H₃CO₄.

Refuting Creationism - The 'Smoking Gun' of Life On Early Mars

Daybreak at the Gale Crater on Mars where organic material was found.

Photo: NASA/JPL-Caltech/MSSS

Mount Sharp in the centre of Gale Crater where organic material was found by Curiosity Rover

Photo: NASA/JPL-Caltech/MSSS

Organic material from Mars reveals the likely origin of life’s building blocks – University of Copenhagen

Those creationists who understand the implication for their superstition will be dreading the discovery of evidence of life elsewhere in the Universe, so to have it discovered on our neighbouring planet in the solar system will be doubly worrying for them.

The reason for this fear is that they have invested so much of their argument for a magic creator in a proclaimed vast unlikelihood to the point of impossibility, of inorganic elements forming themselves into organic molecules - the basic building blocks of living systems. Combine that with their false dichotomy fallacy which says the only possibility is that their locally popular god did it, and you have the basis of the creationist argument from 'impossible' abiogenesis.

So, discovering that it happened on Mars shows that not only is it not impossible, nor even highly unlikely, but it happens when the conditions are right as easily as mixing hydrochloric acid and sodium hydroxide gives table salt (\(\small \text{HCl} + \text{NaOH} \rightarrow \text{NaCl} + \text{H}_2\text{O}\)). No magic is needed, and it can all be accounted for with the basic laws of chemistry and physics.

Of course, those creationists who have been preparing for this eventuality will simply declare that their unproven magic creator did it there too. Sadly for them this just leaves them to explain why a supposedly omniscient, super-intelligent creator would create the building blocks for organic life on a planet so singularly unsuitable for living systems as Mars?

What would be the consequences for creationism if the building blocks for living systems were found on Mars? The discovery of the building blocks for living systems on Mars would have significant implications for various perspectives on creationism, particularly in how they interpret the origin and distribution of life. Here are some potential consequences:

1. Young Earth Creationism (YEC):
   • Challenge to Beliefs: YEC proponents typically believe that Earth and life were created relatively recently (within the last 10,000 years) and uniquely by divine action. Finding the building blocks of life on Mars could challenge the view that Earth is the exclusive site of creation.
   • Reinterpretation of Evidence: YEC advocates might argue that these building blocks were either created by God on Mars or arrived there via panspermia from Earth, thus maintaining that life is still unique to God's creation on Earth.
2. Old Earth Creationism (OEC):
   • Expanded View of Creation: OEC proponents, who accept the scientific consensus on the age of the Earth but believe that life was created by God over billions of years, might see the discovery as evidence of a broader scope of divine creation. They might argue that God created life or its precursors not only on Earth but also elsewhere in the universe.
   • Integration with Science: OEC might integrate this discovery into their worldview, suggesting that the building blocks of life are a part of God's creative design and could be expected to be found throughout the universe.
3. Intelligent Design (ID):
   • Support for Design Hypothesis: Proponents of ID, who argue that life is too complex to have arisen without an intelligent cause, might interpret the discovery of life's building blocks on Mars as further evidence of a purposeful design by an intelligent entity. They could argue that life's building blocks being present on multiple planets supports the idea of a designed and purposeful universe.
   • New Arguments for Design: ID proponents might develop new arguments or refine existing ones to account for the distribution of life's building blocks, using this discovery to bolster their claims about the prevalence of design in the universe.
4. Progressive Creationism:
   • Alignment with Existing Beliefs: Progressive creationists, who believe that God intervened at various points to create new forms of life, might view the presence of life's building blocks on Mars as part of God's creative process. They could argue that these building blocks were placed there as part of a divine plan that includes multiple planets.
   • Divine Purpose and Planning: This perspective might emphasize the idea that God's creative work extends beyond Earth, highlighting a divine purpose that includes the entire cosmos.
5. Theistic Evolution:
   • Compatibility with Science: Theistic evolutionists, who believe that God works through the process of evolution, would likely see the discovery as consistent with their view that the natural processes observed by science are the means through which God creates life. They might argue that finding life's building blocks on Mars is evidence of the widespread potential for life in the universe, as part of God's natural order.
   • Reinforcement of Universal Creation: This perspective might interpret the discovery as reinforcing the idea that life is a fundamental aspect of God's creation and that the potential for life exists throughout the universe.

In summary, while the discovery of the building blocks for living systems on Mars would challenge some specific creationist views, it would also offer an opportunity for reinterpretation and integration within other creationist frameworks. The response would vary depending on the particular beliefs and theological interpretations of each creationist perspective.

Is it the act of an intelligent creator to create the building blocks of life on a planet such as Mars which is singularly unsuitable for life as we know it to exist on?

The question of whether it is the act of an intelligent creator to create the building blocks of life on a planet such as Mars, which is currently unsuitable for life as we know it, can be approached from various perspectives, each influenced by different theological, philosophical, and scientific viewpoints. Here are several possible interpretations:

1. Testing Grounds for Life:
   • Perspective: Some might argue that an intelligent creator could place the building blocks of life on Mars as a kind of experiment or preparation for life that might develop under different conditions.
   • Rationale: This could be seen as a way for the creator to ensure that the building blocks of life are universally distributed, giving life the potential to arise in diverse environments, possibly under conditions that we do not yet fully understand or recognize.
2. Part of a Larger Plan:
   • Perspective: From a theological standpoint, the presence of life's building blocks on Mars might be interpreted as part of a grander divine plan that extends beyond our current understanding of habitability.
   • Rationale: Proponents of this view might suggest that Mars could have been more suitable for life in the past or could become suitable again in the future, or that these building blocks serve a purpose in ways that are not immediately apparent to us.
3. Evidence of Universal Design:
   • Perspective: Some advocates of intelligent design or creationism might see the widespread distribution of life's building blocks as evidence of a purposeful design by an intelligent creator.
   • Rationale: This perspective might hold that the creator designed the universe with the potential for life in various forms, and that the presence of these building blocks on Mars reflects the creator's intention for life to potentially arise or be studied in different environments.
4. Scientific Explanation with Theistic Interpretation:
   • Perspective: Theistic evolutionists or those who integrate science and faith might view the presence of life's building blocks on Mars as a natural consequence of the laws and processes set in motion by a creator.
   • Rationale: They might argue that life's building blocks are naturally distributed by processes such as asteroid impacts, comets, or interplanetary dust, which are part of the universe's design. This distribution could be seen as evidence of a universe finely tuned to produce and support life.
5. Philosophical and Existential Considerations:
   • Perspective: From a philosophical standpoint, the discovery might provoke questions about the nature of life and the conditions necessary for it, expanding our understanding of what it means for a planet to be "suitable" for life.
   • Rationale: This could lead to a broader consideration of life as a phenomenon that might not be confined to Earth-like conditions, suggesting that the creator's intentions might encompass a wider variety of life forms and habitats than we currently imagine.

In conclusion, the interpretation of an intelligent creator placing the building blocks of life on Mars depends heavily on one's worldview. Some may see it as a sign of a larger, incomprehensible plan or an evidence of a designed and purposeful universe, while others may integrate it into a scientific framework that does not necessarily require direct divine intervention. The suitability of Mars for life as we know it might be less relevant in these discussions than the broader implications of finding life's precursors beyond Earth.

In other words, it must be intelligently designed because it was designed by an intelligent designer? Is that a rational argument?

The argument that "it must be intelligently designed because it was designed by an intelligent designer" is an example of a circular argument. In logic, a circular argument is one in which the conclusion is assumed in one of the premises. Here's a breakdown of why this is considered circular and why it may not be rational:

Structure of the Argument

1. Premise: The building blocks of life on Mars are intelligently designed.
2. Conclusion: Therefore, they were designed by an intelligent designer.

In this structure, the premise assumes what it is trying to prove (i.e., that the building blocks are intelligently designed).

Rational Evaluation

1. Begging the Question: This argument begs the question because it assumes the conclusion within the premise. For an argument to be rational and persuasive, it should provide independent support for its conclusion rather than assume it from the outset.
2. Lack of Independent Evidence: For the argument to be rational, it would need to provide independent evidence or reasoning to support the claim that the building blocks of life on Mars were designed by an intelligent designer. This might include evidence of complexity that cannot be explained by natural processes, specific patterns that indicate design, or other empirical data that suggest intelligent intervention.
3. Alternative Explanations: A rational argument should also consider and address alternative explanations. In this case, it should examine naturalistic explanations for the presence of life's building blocks on Mars, such as abiogenesis, panspermia, or chemical processes that could occur without intelligent intervention.

How to Make a Rational Argument for Intelligent Design

To construct a more rational argument for the intelligent design of the building blocks of life on Mars, one could:

1. Present Empirical Evidence: Provide specific examples of features or characteristics of the building blocks that strongly suggest design over natural processes. This might include irreducible complexity or specified complexity that natural processes cannot easily account for.
2. Demonstrate the Inadequacy of Natural Explanations: Show why natural processes (e.g., chemical evolution, random molecular interactions) are insufficient to account for the building blocks' presence and complexity.
3. Use Inference to the Best Explanation: Argue that intelligent design is the best explanation among competing hypotheses based on the evidence available. This involves comparing the explanatory power and scope of intelligent design versus naturalistic explanations.

Example of a Rational Argument

An example of a more rational argument might look like this:

1. Premise 1: The building blocks of life exhibit patterns and complexities (e.g., molecular structures, chirality) that are highly unlikely to arise through known natural processes.
2. Premise 2: Such patterns and complexities are best explained by the action of an intelligent cause, as they resemble known products of intelligence (e.g., human-engineered molecules).
3. Conclusion: Therefore, it is reasonable to infer that the building blocks of life on Mars were designed by an intelligent cause.

This argument provides premises that can be independently evaluated and supports the conclusion with evidence rather than assuming it.

In summary, the assertion that "it must be intelligently designed because it was designed by an intelligent designer" is circular and not rational by itself. A rational argument would need to provide independent evidence and reasoning to support the conclusion of intelligent design.

Wouldn't one need to provide empirical evidence a priori that an entity capable of designing anything actually exists, otherwise is should be pared away using Occam's Razor.

Yes, according to principles of logical reasoning and empirical investigation, providing empirical evidence that an entity capable of designing anything exists is essential for the argument of intelligent design to be robust. Additionally, Occam's Razor, which favors simpler explanations with fewer assumptions, would suggest that without such evidence, the hypothesis of an intelligent designer should be set aside in favor of naturalistic explanations that do not require the introduction of additional, unproven entities. Here’s a more detailed examination:

Empirical Evidence of an Intelligent Designer

To argue convincingly for intelligent design, one must:

1. Demonstrate the Existence of the Designer: Present empirical evidence or a logically coherent argument that an intelligent designer exists. This might include evidence from cosmology, biology, or other fields that point to the presence of a designing intelligence.
2. Show Capability and Action: Provide evidence that this designer has the capability to create life and has acted to do so. This would involve showing that the designer has the necessary attributes (such as intelligence, power, and intention) and has indeed performed acts of creation or design.

Application of Occam's Razor

Occam's Razor is a heuristic tool that helps to eliminate unnecessary assumptions:

1. Naturalistic Explanations: If naturalistic explanations (such as abiogenesis, chemical evolution, or panspermia) can account for the presence of life’s building blocks without invoking an intelligent designer, then these explanations are generally preferred. They do not require assuming the existence of an additional entity.
2. Parsimony: The principle of parsimony suggests that we should not multiply entities beyond necessity. Therefore, if the existence of an intelligent designer is not empirically demonstrated and is not necessary to explain the phenomenon, it should be excluded from the explanation.

Example of Applying Occam's Razor

Consider two hypotheses to explain the presence of life’s building blocks on Mars:

1. Naturalistic Hypothesis: The building blocks of life are the result of chemical processes that occur naturally in the universe, possibly delivered via meteorites or formed through planetary processes.
2. Intelligent Design Hypothesis: An intelligent designer placed the building blocks of life on Mars.

Evaluation:

• Naturalistic Hypothesis: This requires the assumption that natural chemical processes can produce life’s building blocks, which is supported by scientific evidence and does not require additional assumptions about the existence of an intelligent entity.
• Intelligent Design Hypothesis: This requires the assumption of an intelligent designer, whose existence and capabilities must be independently verified. Without empirical evidence of such a designer, this hypothesis adds an unnecessary layer of complexity.

Using Occam’s Razor, the naturalistic hypothesis is preferred because it is simpler and relies on fewer assumptions.

Conclusion

For the intelligent design hypothesis to be considered rational and preferable:

1. Empirical Evidence Required: There must be empirical evidence for the existence of an intelligent designer capable of creating life’s building blocks.
2. Simplicity and Parsimony: In the absence of such evidence, the hypothesis should be set aside in favor of simpler, naturalistic explanations that do not require additional, unproven entities.

Therefore, without prior empirical evidence of an intelligent designer, the hypothesis of intelligent design is less favored by Occam's Razor compared to naturalistic explanations.

But find it they have, or at least the 'smoking gun' that shows the basic building blocks for organic molecules existed on the early Mars. How the team of scientists from the University of Copenhagen did so is the subject of an open access research aper in Nature Geoscience and a detailed news release from Copenhagen University.

Before continuing, any creationists preparing to dismiss this with their traditional 'God did it! parrot squawk would be well advided to read the panel on the right, especially the final section on a priori evidence and the use of Occam's Razor.

Organic material from Mars reveals the likely origin of life’s building blocks

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Mars Two samples from Mars together deliver the "smoking gun" in a new study showing the origin of Martian organic material. The study presents solid evidence for a prediction made over a decade ago by University of Copenhagen researchers that could be key to understanding how organic molecules, the foundation of life, were first formed here on Earth.

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In a meteor crater on the red planet, a solitary robot is moving about. Right now it is probably collecting soil samples with a drill and a robotic arm, as it has quite a habit of doing. NASA's Curiosity rover has been active on Mars as the extended arm of science for nearly 12 years, and it continues to make discoveries that surprise and challenge scientists' understanding of both Mars and our own world here on Earth.

Facts: Organic material

The sample found on Mars contains deposits of so-called organic material.

To laymen this may sound more exciting than it is. Organic material in a chemical context does not necessarily mean something living, as one might normally think. The term covers molecules that contain carbon and at least one other element and can easily exist without life. These molecules are rather the building blocks of life.

Most recently, the discovery of sedimentary organic material with particular properties has had many researchers scratching their heads. The properties of these carbon-based materials, in particular the ratio of its carbon isotopes, surprised researchers.

Organic materials with such properties, if found on Earth, would typically be a sign of microorganisms, but they can also be the result of non-biological, chemical processes. The find obviously had researchers scrambling for a clear answer, but nothing seemed to fit.

However, for the research collaboration behind a study published in Nature Geoscience, there has been little hair scratching and much enthusiasm.

In fact, the discovery on Mars provided the missing piece that made everything fall into place for this group of researchers from the University of Copenhagen and the Tokyo Institute of Technology.

As co-author and chemistry professor Matthew Johnson puts it, it is "the smoking gun" needed to confirm a decade old theory of his about so-called photolysis in Mars' atmosphere.

With the Curiosity sample, the new research is able to prove with reasonable certainty that the Sun broke down \(\small\ce{CO2}\) in the Martian atmosphere billions of years ago - as the old theory predicted. And that the resulting carbon monoxide gradually reacted with other chemicals in the atmosphere synthesizing complex molecules – and thus providing Mars with organic materials.

Facts: What is Photolysis

Photolysis means that the Sun's UV rays provide molecules with energy to perform a chemical transformation. According to the research this happened in the Martian atmosphere, where 20% of \(\small\ce{CO2}\) molecules there were split into oxygen and carbon monoxide.

In earlier research, Johnson and colleagues showed that carbon dioxide containing the carbon-12 isotope is photolysed more quickly than the heavier isotope carbon-13. Over time, \(\small\ce{CO}\) is produced that is depleted in \(\small\ce{^13C}\), and \(\small\ce{^13C}\) builds up in the remaining \(\small\ce{CO2}\). This results in so-called isotopic enrichment in \(\small\ce{CO2}\) and depletion in \(\small\ce{CO}\), like mirror images or each other or the two halves of a broken plate.

It is the fractionation ratio in carbon, which serves as evidence of photolysis in the two samples from Mars.

Such carbon-based complex molecules are the prerequisite of life, the building blocks of life one might say. So, this it is a bit like the old debate about which came first, the chicken or the egg. We show that the organic material found on Mars has been formed through atmospheric photochemical reactions - without life that is. This is the 'egg', a prerequisite of life. It still remains to be shown whether or not this organic material resulted in life on the Red Planet. Additionally because Earth, Mars and Venus had very similar \(\small\ce{CO2}\) rich atmospheres long ago when this photolysis took place, it can also prove important for our understanding of how life began on Earth.

Professor Matthew Johnson, co-author
Department of Chemistry
University of Copenhagen, Copenhagen, Denmark.

Two pieces separated by 50 Million Kilometers – one puzzle solved

12 years ago Johnson and two colleagues used simulations based on quantum mechanics to determine what happens when a \(\small\ce{CO2}\) rich atmosphere is exposed to the UV-light of the Sun, in a process known as photolysis.

Facts: Isotopes Have Different Weights

Isotopes are variants of the same element that have different weights because the nucleus contains more or fewer neutrons.

Carbon has two stable isotopes - Normally, about 99% of carbon has 6 protons and 6 neutrons in its nucleus (\(\small\ce{^12C}\)). About 1% has 6 protons and 7 neutrons instead (\(\small\ce{^13C}\)). The ratio can serve as a chemical fingerprint revealing what reactions the carbon has undergone.

Photolysis favors carbon-12, and a high concentration of the isotope can therefore indicate this process.

Basically, on Mars around 20% of the \(\small\ce{CO2}\) is split into oxygen and carbon monoxide. But carbon has two stable isotopes: carbon-12 and carbon-13. Usually they are present in a ratio of one carbon-13 for every 99 carbon-12. However, photolysis works faster for the lighter carbon-12, so the carbon monoxide produced by photolysis has less carbon-13 (is depleted), and the left over \(\small\ce{CO2}\) has more (is enriched). Because of this, Johnson and his colleagues were able to make very precise predictions of the ratio of carbon isotopes after photolysis. And this gave them two distinctive fingerprints to look for. One of these was identified in a different Martian sample, years ago.

We actually have a piece of Mars here on Earth, which was knocked off that planet by a meteorite, and then became one itself, when it landed here on Earth. This meteorite, called Allan Hills 84001 for the place in Antarctica where it was found, contains carbonate minerals that form from \(\small\ce{CO2}\) in the atmosphere. The smoking gun here is that the ratio of carbon isotopes in it exactly matches our predictions in the quantum chemical simulations, but there was a missing piece in the puzzle. We were missing the other product of this chemical process to confirm the theory, and that's what we've now obtained.

Professor Matthew Johnson.

Extra Info: The Famous Mars Meteorite

The discovery of organic sediments on Mars with a low ratio of carbon-13 completes the puzzle of empirical evidence for the photolysis theory, since researchers already found the other part of that puzzle years ago in the famous meteorite, Allan Hills 84001. The meteorite contains carbonate with a heightened concentration of heavy carbon 13 isotopes.

Discovered in Antarctica 40 years ago by Roberta Score, the meteorite is believed to originate from the Red Planet and became particularly well known because it contains some deposits that led NASA researchers to announce in 1996 that they believed they had found traces of microscopic fossils of bacteria from Mars.

Today, the consensus is that these deposits are abiotic - that is, stemming from non-biological processes.

The carbon in the Allan Hills meteorite is enriched in carbon-13, which makes it the mirror image of the depletion in carbon-13 that has now been measured in the organic material found by Curiousity on Mars.

The new study has thus linked data from two samples, which researchers believe have the same origin in Mars' childhood but were found more than 50 million kilometers apart.

There is no other way to explain both the carbon-13 depletion in the organic material and the enrichment in the Martian meteorite, both relative to the composition of volcanic \(\small\ce{CO2}\) emitted on Mars, which has a constant composition, similar as for Earth’s volcanos, and serves as a baseline.

Professor Matthew Johnson.

Hope to find the same evidence on Earth

Because the organic material contains this isotopic “fingerprint” of where it came from, researchers are able to trace the source of the carbon in the organic material to the carbon monoxide formed by photolysis in the atmosphere. But this also reveals a lot about what happened to it in between.

Facts: The oxygen painted Mars red

Photolysis of a \(\small\ce{CO2}\) molecule yields carbon monoxide (\(\small\ce{CO}\)) and an oxygen atom (\(\small\ce{O}\)). On Mars, only carbon monoxide remains, which is transformed into the organic material found by the Curiosity rover.

But where the oxygen has gone is also no secret. The oxygen combines into \(\small\ce{O2}\), which interacts with iron on Mars' surface. The Red Planet is rust red due to oxidized iron.

This shows that carbon monoxide is the starting point for the synthesis of organic molecules in these kinds of atmospheres. So we have an important conclusion about the origin of life’s building blocks. Although so far only on Mars.

Professor Matthew Johnson.

Researchers hope to find the same isotopic evidence on Earth, but this has yet to happen, and it could be a much bigger challenge because our geological development has changed the surface significantly compared to Mars, Johnson explains.

It is reasonable to assume that the photolysis of \(\small\ce{CO2}\) was also a prerequisite for the emergence of life here on Earth, in all its complexity. But we have not yet found this “smoking gun” material here on Earth to prove that the process took place. Perhaps because Earth's surface is much more alive, geologically and literally, and therefore constantly changing. But it is a big step that we have now found it on Mars, from a time when the two planets were very similar.

Professor Matthew Johnson.

Extra info: Mars, Earth, and Venus Had the Same Atmosphere

According to researchers, Earth had approximately the same atmosphere as our neighboring planets Mars and Venus billions of years ago.

When the early planets Venus, Earth, and Mars eventually formed solid surfaces, researchers believe they began to release large amounts of \(\small\ce{CO2}\) from extreme volcanic activity. That's how they formed their first atmospheres with large concentrations of the gas. Oxygen had not yet become part of the atmosphere; this happened later on Earth, after the emergence of life.

The photolysis theory states that UV rays from the sun then start a chain of chemical reactions. A chain that starts with the breakdown of \(\small\ce{CO2}\) into carbon monoxide, which is the building block for a multitude of other chemical compounds.

Thus, with the help of the Sun, the foundation for the many carbon compounds and complex molecules we have today was formed - in the case of Earth, the foundation for life.

Since then the fate of the three planets has been significantly different. Earth's carbon dioxide reacted with our large amount of surface water and much of it deposited over time as carbonate rocks like limestone, leaving the atmosphere dominated by nitrogen, as we have today. Life arose, and microorganisms produced oxygen, which, among other things, created our ozone layer, while Mars and Venus still have very \(\small\ce{CO2}\)-dominant atmospheres today.

Professor Matthew Johnson.

Today, Venus has a very dense and toxic atmosphere primarily of \(\small\ce{CO2}\) which gives it a surface temperature of around 450 degrees Celsius. On Mars, the atmosphere has become much thinner compared to Earth's, and has left a desert landscape.

About the new study:

The study is published in Nature Geoscience and has just appeared in the journal's June issue. The following researchers have contributed to the new study:

From the Department of Chemistry at the University of Copenhagen:

Matthew S. Johnson and Johan A. Schmidt

From the Tokyo Institute of Technology:

Yuichiro Ueno, Xiaofeng Zang, Alexis Gilbert, Hiroyuki Kurokawa and Tomohiro Usui

From the University of Tokyo and the Royal Belgian Institute of Space Aeronomy:

Shohei Aoki

Abstract
Organic matter found in early Martian sediment may yield clues to the planet’s environmental conditions, prebiotic chemistry and habitability, but its origin remains unclear. Strong (\(\small\ce{^13C}\)) depletion in sedimentary organic matter at Gale crater was recently detected by the Curiosity rover. Although this enigmatic depletion remains debated, if correct, a mechanism to cause such strong (\(\small\ce{^13C}\)) depletion is required. Here we show from \(\small\ce{CO2}\) photolysis experiments and theoretical considerations that solar ultraviolet photolysis of \(\small\ce{CO2}\) in a reducing atmosphere can yield strongly (\(\small\ce{^13C}\))-depleted \(\small\ce{CO}\). We suggest that atmospheric synthesis of organic compounds from photolysis-produced \(\small\ce{CO}\) is a plausible mechanism to explain the source of isotopically depleted organic matter in early Martian sediments. Furthermore, this mechanism could explain (\(\small\ce{^13C}\)) enrichment of early Martian \(\small\ce{CO2}\) without requiring long-term carbon escape into space. A mass balance model calculation using our estimated isotopic fractionation factor indicates the conversion of approximately 20% of volcanic \(\small\ce{CO2}\) emissions on early Mars into organics via \(\small\ce{CO}\), consistent with the available data for carbon isotopes of carbonate. Although alternative pathways for organic compound production have been proposed, our findings suggest that considerable amounts of organic matter may have been synthesized from \(\small\ce{CO}\) in a reducing early Martian atmosphere and deposited in sediments.

Main
Organic matter on Mars is important for understanding the habitability of the planet, prebiotic chemistry and the search for life in the universe. A series of analyses using the Sample Analysis at Mars (SAM) instrument on board the Curiosity rover discovered and confirmed that there is sedimentary organic matter preserved in circa 3.5-billion-year-old water-lain sediment at the Gale crater on Mars^1,2,3,4. Furthermore, recent analysis of SAM data revealed that this organic matter has an enigmatic stable carbon isotope composition \(\small\delta^{13}\text{C}_{\text{VPDB}}\) values [\(\small\equiv 1000 \left( \left( \frac{^{13}\text{C}}{^{12}\text{C}} \right)_{\text{sample}} \bigg/ \left( \frac{^{13}\text{C}}{^{12}\text{C}} \right)_{\text{VPDB}} - 1 \right)\)] from −137‰ to +22‰) (refs. ^5,6,7,8,9), some of which are strongly depleted in (\(\small\ce{^13C}\)) to an extent never found in Earth’s sedimentary rocks⁶. Although some in situ isotope analyses have been contaminated by a terrestrial material mixed into the SAM instrument^{3,4,5,6,7,8,9,10}, even taking this into account, it appears that several early Martian sediments contain organic carbon with \(\small\delta^{13}\text{C}_{\text{VPDB}}\) values at least less than −70‰ (ref. 10) and possibly down to −137 ± 8‰ (refs. ^6,8) (Supplementary Note provide details). The origin of this strong (\(\small\ce{^13C}\)) depletion remains uncertain but may arise from cosmic, biological or abiological processes^4,5,6. Interplanetary dust may include carbon particles with strong (\(\small\ce{^13C}\)) depletion¹¹ and might have accumulated in the sediment⁶, although the signal from outside the solar system would easily be diluted if indigenous carbon sources were available from biotic or abiotic processes on Mars. Some biological metabolic pathways, particularly methanotrophy, can induce large isotopic fractionation, but it is difficult to explain \(\small\delta^{13}\text{C}_{\text{VPDB}}\) < −100‰ in light of known biological fractionation factors⁶. In principle, the organic matter in early Martian sediment could be due to abiotic reactions such as Fischer–Tropsch-type reactions^2,6 or electro-chemical reduction of \(\small\ce{CO2}\)^5,6,12, but none of these mechanisms are known to produce the large carbon isotopic fractionations observed (ref. ⁶ and references therein). An alternative source of organic matter is atmospheric synthesis^{5,6,13,14,15,16}. Theoretically, atmospheric photochemistry under the appropriate conditions may produce a large carbon isotopic fractionation^14,15,17. Ab initio calculations using time-dependent wavepacket propagation of the absorption cross sections of \(\small\ce{CO2}\) isotopologues¹⁷ predicted that solar UV photolysis of \(\small\ce{CO2}\) yields strongly (\(\small\ce{^13C}\))-depleted \(\small\ce{CO}\), potentially lower than −100‰ (Fig. 1). However, the large isotope effect has not yet been verified by laboratory experiment^17,18.

Fig. 1: Wavelength-dependent isotopic fractionation of \(\small\ce{CO2}\) photolysis.

Preferential dissociation of \(\small\ce{^12CO2}\) against \(\small\ce{^13CO2}\) is expected in a wavelength region from 170 nm to 200 nm, which is responsible for solar UV photolysis of \(\small\ce{CO2}\). a, Actinic UV spectra. Red: solar spectrum from ref. ⁴³. Blue: calculated spectrum at 30 km altitude (alt.) of model early Mars (10 mbar \(\small\ce{CO2}\) at surface) (Methods). Black: measured UV spectrum of the high pressure Xe lamp used in the laboratory experiment (Methods). b, Calculated absorption cross sections of \(\small\ce{^12CO2}\) (black) and \(\small\ce{^13CO2}\) (orange) at 295 K from ref. ¹⁷. c, Calculated isotope effect (1,000 ln α₁) as a function of wavelength for the 295 K absorption spectra. Results were averaged over a 1 nm (black) and 5 nm (red) windows. Oxygen isotopic fractionation and its implications for Mars atmosphere were given elsewhere¹⁷.

Explaining the origin of the strong (\(\small\ce{^13C}\)) depletion becomes even more problematic considering that the early carbonate precipitate in the approximately 4 billion years old (4 Ga) Martian meteorite ALH 84001 was rather enriched in (\(\small\ce{^13C}\)) (up to +55‰) (refs. ^19,20,21) relative to Mars mantle carbon (\(\small\delta^{13}\text{C}_{\text{VPDB}}\) = −25 ± 5‰) (ref. ²²) (Methods). For present-day Mars, the (\(\small\ce{^13C}\)) enrichment of atmospheric \(\small\ce{CO2}\) (\(\small\delta^{13}\text{C}_{\text{VPDB}}\) = +46 ± 4‰) (ref. ²³) has been thought to result from carbon escape into space^14,24,25 through the 4-billion-year history of Mars. However, even assuming the 4 Ga carbonate were in equilibrium with the atmospheric \(\small\ce{CO2}\), its \(\small\delta^{13}\text{C}_{\text{VPDB}}\) value should have already been enriched in (\(\small\ce{^13C}\)) ( + 20 ± 10‰) at that time (Methods provide details). It is problematic to understand whether several hundred million years after formation of Martian atmosphere, enough time has passed to create the (\(\small\ce{^13C}\)) enrichment of \(\small\ce{CO2}\) only via carbon escape into space^14,25. Furthermore, based on geomagnetic observations²⁶, early Mars probably had a geomagnetic field before 4 Ga. The geomagnetic field on early Mars could have prevented solar winds from interacting with ions in the upper atmosphere and shielded the neutral atmosphere from sputtering loss. Robust magnetic shielding of the atmosphere before 4 Ga is supported by observations of low-fractionated atmospheric argon (\(\small\ce{^38Ar}\)/\(\small\ce{^36Ar}\)) and nitrogen (\(\small\ce{^15N}\)/\(\small\ce{^14N}\)) recorded in ALH 84001^27,28. Therefore, (\(\small\ce{^13C}\)) enrichment of Mars’ early carbonate is still enigmatic and may have been caused by other fractionation processes^14,25,29. Here we present a new laboratory experiment and quantum theoretical and model calculations that demonstrate how solar UV photolysis of \(\small\ce{CO2}\) and subsequent organic synthesis from atmospheric \(\small\ce{CO}\) could explain both the strong (\(\small\ce{^13C}\)) depletion in the organic matter and the (\(\small\ce{^13C}\)) enrichment of \(\small\ce{CO2}\). A previous \(\small\ce{CO2}\) photolysis experiment¹⁸ was conducted using an ultraviolet light source with a confined wavelength at 184.9 nm, which does not simulate the actual fractionation that occurs in a planetary atmosphere where the expected isotope effect depends on the broad distribution of wavelengths of the actinic UV flux¹⁷ (Fig. 1). Therefore, we used a solar-like broadband UV source for \(\small\ce{CO2}\) photolysis (Fig. 1a) to confirm the large carbon isotope effect and quantify the actual fractionation factor associated with \(\small\ce{CO2}\) photolysis in the early Martian atmospheres.

It's going to be interesting watching creationists trying to ignore the evidence, that this finding establishes, that the natural creation of building blocks of life is not impossible nor even highly unlikely, but happens as readily as any other chemical reaction in the presense of inorganic molecules that were abundant on early Earth, as on early Mars. No god-magic required.

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