Religion, Creationism, evolution, science and politics from a centre-left atheist humanist. The blog religious frauds tell lies about.
Saturday, 9 November 2024
Refuting Creationism - What Did The Denisovans Ever Do For Us?
New insights into the Denisovans – the new hominin group that interbred with modern day humans - News & Events | Trinity College Dublin
In marked contrast to the childish creationist notion of a single founder couple being magically created without ancestors 6-10,000 years ago, evidence is growing that one ancestral species that contributes some of its DNA to modern non-African humans, the Denisovans, were once widespread especially in Southeast Asia and may have reached South America, or at least people carrying some Denisovan DNA may have done, but not via the traditional route - Siberia, Beringia and Alaska - followed by later Homo sapiens.
My understanding is that they and Neanderthals were most likely direct descendants of H. erectus that migrated out of Africa some 2 million years ago and gave rise to the Denisovans in Eastern Eurasia and Neanderthals in Western Eurasia. These two then interbreed with the H. sapiens migrants as they came up out of Africa and spread throughout Eurasia and down to Melanesia, Austronesia and Oceania.
So, rather than a single ancestral couple magically created out of dirt, without ancestors, as creationists believe, modern non-African humans don't have an ancestral couple, they don't even have a single ancestral species but are the result of hybridization between at least three ancestral species.
There is also evidence, according to two researchers from Trinity College, Dublin, Ireland, that there may have been several regional populations of Denisovans, each of which contributed to the Homo sapiens genome at different times. As with other hominin species, they were diversifying as they spread in what may have been the beginnings of classical allopatric speciation.
The Denisovan DNA that was retained by H. sapiens as they migrated into the different environments in Asia was that which gave them an advantage, such as the ability to survive in the low oxygen partial pressure of the Tibetan Plateau - something that the Tibetans have inherited - immunity to certain endemic pathogens and an improved ability to keep their body temperature up during cold weather by burning stored body fats - something that Innuits have inherited.
Tuesday, 15 October 2024
Refuting Creationism - The Japanese People Didn't Notice Noah's Genocidal Flood!
Traces of ancient immigration patterns to Japan found in 2000-year-old genome | SCHOOL OF SCIENCE THE UNIVERSITY OF TOKYO
Being parochial Bronze Age pastoralists who knew about nothing and nowhere that was more than a day or two's walk from their hill pastures in Canaan, those who made up the Hebrew creation myths could not possibly have been aware that there were other cultures in far-away places like China, Korea and Japan, which had ancient histories going way back before the myth-makers thought Earth was created, and which were unscathed by an global flood at the time in which they set that tale.
Had they been aware of them, they could have made up slightly more plausible myths with a more realistic timeline, instead of requiring their believers to try to compress everything that's happened in the entire 14-billion-year-old Universe into 10,000 years.
But how could they have done so when they had no-one to teach them the real history of the planet and the people living on it? All they had was their own limited imagination and a handful if inherited myths from neighbouring culture, like Egypt and Sumeria, for theirs was a backward, illiterate culture from the fearful infancy of our species, dependent on oral traditions and superstitions.
How could they possibly have known, for example, that a population of humans had been more or less isolated for about 6,500 years, ending at about the time the myth-makers believed Earth was made out of nothing by magic, complete with a dome over it to cover the small, flat place they called home? They would have known nothing about immigration from China or from the Korean Peninsula into the Japanese archipelago that brought this period of isolation to an end and probably resulted in the present-day population of Japan.
So, of course, they saw nothing wrong with inventing a tale about a genocidal flood killing everyone apart from 8 related survivors, or of building a tower to reach above the dome or about a panicking god making them all speak different languages so they couldn't work in cooperative groups any more, and yet, if their tale is to be believed, the descendants of those few survivors, all speaking different languages, migrated to places like China, Korea and Japan where they all adopted the local language and writing that had been used for several thousand years, forgot all about Noah and his flood and invented new gods and religions, whereas the myth-makers of Canaan remembered it all word-perfect in every detail...
So, how do we know the record they left was wrong?
Friday, 11 October 2024
Refuting Creationism - Humans Were Using Fire In Southeast Asia 42,000 Years Before 'Creation Week'
Fossils and fires: insights into early modern human activity in the jungles of Southeast Asia – News
At the same time that creationists believe their small god was making a universe consisting of a small flat planet with a dome over it in the Middle East, then magicking a man a d a woman without ancestors, real humans were living in the jungles of Southeast Asia and making camp fires, around which they were probably making up origin myths just like the Middle Eastern Bronze Age pastoralists did. The difference was, their myths didn't get written down and included in a book declared to be the inerrant word of a magic man in the sky, so they aren't available to fool gullible people with today.
Instead, they left tangible records of their activities that scientists are now discovering and dating to between 52,000 and 10,000 years ago; records moreover that if the campfire tales of the Middle East had any truth in them would have been swept away and destroyed or covered with a deep layer of silt containing the bodies and remains of the animals and plants destroyed in the mythical global genocidal flood inflicted on the planet by an irascible magic despot.
Ironically, the human remains found buried in sediment in a cave floor were probably washed into the cave by a local flood, so all the other fossils at that location are also of local species, not the world-wide jumble that a global flood would have produced.
Tell me about the prehistoric history of the humans who occupied the Tam Pà Ling cave in Laos, please. The Tam Pà Ling cave, located in northern Laos, has yielded some of the most significant prehistoric human remains in Southeast Asia, providing key insights into the early human migrations in the region. The cave, whose name means "Cave of the Monkeys," sits at around 1,170 meters above sea level in the Annamite Mountains, making it an ideal site for shelter during prehistoric times.The cave is the Tam Pà Ling cave, located in northern Laos where Laotian, French, American and Australian archaeologists have been working for some 14 years to unearth the secrets contained in it.
Key Findings and Human Occupation
The site became famous when researchers unearthed several human fossils, including a cranium and jawbones, that have been radiocarbon dated between 46,000 and 63,000 years ago. These discoveries suggest that anatomically modern humans (*Homo sapiens*) were present in Southeast Asia much earlier than previously believed. The remains from Tam Pà Ling are considered some of the oldest evidence of modern humans in mainland Asia.
Significance in Human Migration
The fossils found in Tam Pà Ling have played an essential role in understanding the "Out of Africa" migration, where *Homo sapiens* spread from Africa to the rest of the world. The cave’s location, relatively close to the Mekong River, is thought to have been part of a corridor that early humans used as they moved from Africa through the Middle East, into South Asia, and ultimately into Southeast Asia and Australia.
The discovery of such early modern human remains in Laos supports the theory that early humans reached Southeast Asia via inland routes, rather than following only coastal paths. This inland route theory aligns with the ecological diversity of the region, which would have provided rich resources for early hunter-gatherer groups.
Anatomical Evidence
The fossils found in Tam Pà Ling are distinctly modern in their features. The skulls exhibit traits that are fully consistent with *Homo sapiens*, such as a high forehead, rounded braincase, and small, flat faces. However, some subtle characteristics, like thicker bones and robustness, indicate potential regional adaptations or the influence of archaic hominins like *Homo erectus* or *Denisovans*, both of whom were known to have existed in the broader region.
Cultural Context
No significant cultural artifacts, such as tools or other evidence of complex human behavior, have been found alongside the fossils in Tam Pà Ling, which leaves some aspects of the lives of these early inhabitants uncertain. Nonetheless, their presence in the cave hints at how early humans adapted to diverse environments—ranging from highland caves like Tam Pà Ling to coastal areas.
Importance in the Global Human Evolution Story
The discovery of these early human remains in Tam Pà Ling has contributed to the global conversation on human evolution. It suggests that *Homo sapiens* coexisted with archaic hominins in Asia longer than once thought. It also challenges the idea that humans primarily spread through coastal routes, indicating that Southeast Asia was likely populated by multiple waves of migration, using both coastal and inland routes.
The Tam Pà Ling site remains an important location for understanding the complexity of early human migration and the spread of *Homo sapiens* across the globe.
Now a new study, led by PhD candidate Vito Hernandez and Associate Professor Mike Morley from the College of Humanities, Arts and Social Sciences at Flinders University, SA, Australia, has reconstructed the ground conditions inside the cave between 52,000 and 10,000 years ago. They have just published their findings in Quaternary Science Reviews and announced them in a Flinders University news release:
Fossils and fires: insights into early modern human activity in the jungles of Southeast Asia
Studying microscopic layers of dirt dug from the Tam Pà Ling cave site in northeastern Laos has provided a team of Flinders University archaeologists and their international colleagues further insights into some of the earliest evidence of Homo sapiens in mainland Southeast Asia.
The site, which has been studied for the past 14 years by a team of Laotian, French, American and Australian scientists, has produced some of the earliest fossil evidence of our direct ancestors in Southeast Asia.
Now a new study, led by PhD candidate Vito Hernandez and Associate Professor Mike Morley from the College of Humanities, Arts and Social Sciences, has reconstructed the ground conditions in the cave between 52,000 and 10,000 years ago.
Using a technique known as microstratigraphy at the Flinders Microarchaeology Laboratory, we were able to reconstruct the cave conditions in the past and identify traces of human activities in and around Tam Pà Ling. This also helped us to determine the precise circumstances by which some of the earliest modern human fossils found in Southeast Asia were deposited deep inside.
Vito C Hernandez, co-lead author
Flinders Microarchaeology Laboratory
College of Humanities, Arts and Social Sciences
Flinders University, South Australia, Australia.
Microstratigraphy allows scientists to study dirt in its smallest detail, enabling them to observe structures and features that preserve information about past environments and even traces of human and animal activity that may have been overlooked during the excavation process due to their minuscule size.
The human fossils discovered at Tam Pà Ling were deposited in the cave between 86,000–30,000 years ago but until now, researchers had not conducted a detailed analysis of the sediments surrounding these fossils to gain an understanding of how they were deposited in the cave or the environmental conditions at the time.
Published in Quaternary Science Reviews, the findings reveal conditions in the cave fluctuated dramatically, going from a temperate climate with frequent wet ground conditions to becoming seasonally dry.
This change in environment influenced the cave’s interior topography and would have impacted how sediments, including human fossils, were deposited within the cave. How early Homo sapiens came to be buried deep within the cave has long been debated, but our sediment analysis indicates that the fossils were washed into the cave as loose sediments and debris accumulating over time, likely carried by water from surrounding hillsides during periods of heavy rainfall.
Associate Professor ,” says Associate Professor W.M. Morley, co-lead author
Flinders Microarchaeology Laboratory
College of Humanities, Arts and Social Sciences
Flinders University, South Australia, Australia.
The team also identified preserved micro-traces of charcoal and ash in the cave sediments, suggesting that either forest fires occurred in the region during the drier periods, or that humans visiting the cave may have used fire, either in the cave or near the entrance.
Publication:This research has allowed our team to develop unprecedented insights into the dynamics of our ancestors as they dispersed through the ever-changing forest covers of Southeast Asia, and during periods of variable regional climate instability.
,Assistant Professor Fabrice Demeter, co-author
Lundbeck Foundation GeoGenetics Centre
Globe Institute
University of Copenhagen, Copenhagen, Denmark.VC Hernandez, MW Morley, AM Bacon, P Duringer, KE Westaway, R Joannes-Boyau, JL Ponche, C Zanolli, P Sichanthongtip, S Boualaphane, T Luangkhoth, JJ Hublin, F Demeter
Late Pleistocene–Holocene (52–10 ka) microstratigraphy, fossil taphonomy and depositional environments from Tam Pa Ling cave (northeastern Laos) Quaternary Science Reviews (2024) 108982. DOI: 10.1016/j.quascirev.2024.108982
The refutation of creationism continues unabated. Not only were there people living in South East Asia tens of thousands of years before creationists think Earth was created by magic, but the remains proving it were washed into the cave by a local flood, which, had it been anything resembling creationism's favourite genocidal flood, would also have washed in non-local debris. And that simply never happened, then or later.Highlights
- Late Pleistocene-Holocene cave sediments from Tam Pà Ling, northeastern Laos, were geoarchaeologically investigated.
- Microstratigraphic analyses were employed.
- Ground and ambient conditions vary in the cave ∼52–10 ka.
Abstract
Fossil evidence for some of the earliest Homo sapiens presence in mainland Southeast Asia have been recovered from Tam Pà Ling (TPL) cave, northeastern Laos. Taphonomic indicators suggest that these human fossils washed into TPL via gradual colluviation at varying times between MIS 5–3, yet no attempt has been made to situate them within the depositional environments of the cave within these periods. This has precluded a deeper appreciation of their presence there and in the surrounding landscape. In this first microstratigraphic study of TPL, we primarily use sediment micromorphology to reconstruct the depositional environments of the cave, relate these environments with the taphonomic history of the human fossils recovered from the upper 4 m of the excavated sequence, and explore how the sediments can better explain the presence of these humans in the area during MIS 3–1 (52–10 ka). Our results demonstrate changes in local ambient conditions from being temperate to arid, with ground conditions often wet during MIS 3 and becoming increasingly seasonal (wet-dry) during MIS 2–1. The changing cave conditions impacted its interior topography and influenced the way sediments (and fossils) were deposited. Preserved combustion biproducts identified in the sediments suggest two possible scenarios, one where small forest fires may have occurred during periods of regional aridity and/or another where humans visited the cave.
1. Introduction
The excavations in Tam Pà Ling (Cave of Monkeys), northeastern Laos (Fig. 1A), have unearthed a fossil assemblage of Homo sapiens that is unique for the study of Late Pleistocene human evolution in Southeast Asia (SEA) (Demeter et al., 2012; Demeter et al., 2015; Demeter et al., 2017; Shackelford et al., 2018; Freidline et al., 2023). The fossil assemblage is formed of a partial cranium (TPL1), two mandibles (TPL2, TPL3), a partial rib (TPL4), a proximal pedal phalanx (TPL5), a partial frontal (TPL6), and a tibial fragment (TPL7), all excavated from a trench situated deep inside the cave. Although disarticulated, the fossils otherwise display minimal evidence of remobilisation or physical abrasion, a rare occurrence from the region (Lee and Hudock, 2021; Sawafuji et al., 2024). As such, the fossils have helped demonstrate the major morphological variations that existed between the different populations of Homo sapiens in SEA during the Late Pleistocene (Demeter et al., 2017), consequently making Tam Pà Ling (TPL) a key site for the study of the evolution and dispersal of our species in the Far East (Matsumura et al., 2019; Demeter and Bae, 2020; Hublin, 2021.1; McAllister et al., 2022; Sawafuji et al., 2024). The TPL fossils represent some of the earliest evidence for Homo sapiens in continental SEA, deposited in the cave at different times between Marine Isotope Stage (MIS) 5b and MIS 3 (∼87–30 ka) (Freidline et al., 2023). Although some of the fossils have been directly dated via uranium–thorium methods, their dates are reported only as minimum age estimates (Demeter et al., 2012, 2015). This is largely due to the unaccounted profiles of uranium from the sampled deposits, noting that tropical environments hold the potential of enhancing heterogeneous distribution of uranium in bones that are chemically weathered in situ. Hence, the modelled depositional ages (2σ) of the containing sediment matrix are preferred when referring to the age of the fossils, with the oldest returned age estimate being ∼86 ka, supporting a much earlier dispersal of Homo sapiens into SEA than previously known. Details of the modelled depositional chronology of TPL are published in Freidline et al. (2023). Whereas palaeoenvironmental reconstructions of the landscape surrounding TPL have provided some context to understand the early dispersal of Homo sapiens in SEA (Milano et al., 2018.1; Bourgon et al., 2021.2; McAllister-Hayward et al., 2024.1), there is still very little understanding of their presence at the site and in the local catchment, other than the occurrence of the fossils. This largely precludes the development of more detailed scenarios for the early Homo sapiens settlement of Asia (Dennell, 2017.1) and achieving a better understanding of their adaptations to environmental changes in tropical landscapes, which are argued to play an important role in human evolution and dispersals in the deep past (Scerri et al., 2022.1 and references therein). In SEA, such knowledge remains elusive due to the limited evidence from the Pleistocene archaeological record and the current resolution of ages that frame the presence of humans at many of the studied sites.
While the ages of the fossils from TPL are well-constrained, the absence of artefacts or occupation surfaces found to date suggests that humans did not intensively occupy the cave during the Late Pleistocene. However, evidence of human presence and occupation at neighbouring sites spanning the Middle Pleistocene to Late Holocene (Demeter et al., 2009; Patole-Edoumba, 2015.1; Bacon et al., 2021.3; Demeter et al., 2022.2, Fig. 1B), and the presence of the fossils from TPL, suggest that humans may have at least visited sporadically or used the cave in the past, even briefly. If so, then traces of their activities from the entrance or even inside might still be preserved, although likely in small quantities, probably degraded, diagenetically altered, or buried beneath limestone slabs.
The research at TPL has simultaneously highlighted the scientific challenges of understanding archaeological site formation processes in the hot and humid tropics (Morley and Goldberg, 2017.2 and references therein), and the need to better understand geomorphological processes that affect the interpretation and dating of fossils from cave sites (Liu et al., 2015.2; Westaway et al., 2017.3; Yao et al., 2020.1). These challenges are made more difficult by the erratic preservation of organic materials in tropical cave environments (Louys et al., 2017.4 and references therein; Smith et al., 2020.2 and references therein), and therefore demand the systematic evaluation of the stratigraphy of a site with the potential to yield bioarchaeological data (e.g., aDNA, proteins) that can inform about humans and their environments in the past (Massilani et al., 2022.3; Morley et al., 2023.1; Aldeias and Stahlschmidt, 2024.2). It is for these reasons that there is a need to better understand the stratigraphy of TPL at various spatial scales (vertical and horizontal) and at finer resolution, with research from other sites in SEA suggesting a geoarchaeology-focused approach to achieve this (O'Connor et al., 2010; Morley, 2017.5).
Sediment micromorphology (microstratigraphy) is one method employed in geoarchaeological research that can help to better understand the geomorphological and site formation processes governing TPL. Research employing this method to study the critical sites for understanding early human evolution and dispersals in SEA show that microstratigraphy can provide a more nuanced picture of local environments in the past, help to reveal more about human adaptations to the different environmental conditions that existed, and temporally resolve the presence of humans on-site and in the immediate catchment (Stephens et al., 2005, 2017.6; Lewis, 2007; Brasseur et al., 2015.3; Mijares, 2017.7; Morley et al., 2017.8; McAdams et al., 2020.3; Anderson et al., 2024.3; Shipton et al., 2024.4). With these in mind, a program of microstratigraphic analysis at TPL was initiated to gain further insights into the history of the site and the taphonomy of the Homo sapiens fossils recovered from there.
To improve the understanding of the history of the site and taphonomy of Homo sapiens fossils recovered from TPL we link the results of the microstratigraphic analysis with loss-on-ignition (LOI) and magnetic susceptibility (χ) analysis of sediments. Both methods provide quick to obtain and accurate determinations of geochemical characteristics that can complement the interpretation of the microstratigraphic record (Stoops, 1978; Macphail and Goldberg, 2017.9). LOI, for instance, has complemented microstratigraphic analysis of archaeological cave sites in Malaysia, northern Vietnam and Thailand, resulting in a clearer understanding of the depositional environments that existed in these caves in the past (Hunt et al., 2007.1; Stephens et al., 2016; McAdams et al., 2020.3; Saminpanya and Denkitkul, 2020.4). While χ has been used at TPL to infer moisture availability that helped to reconstruct the vegetation surrounding the cave during the Late Pleistocene (Milano et al., 2018.1) and allowed insights into the timing of sediment delivery into the cave during periods of strengthened monsoons (Freidline et al., 2023). By linking the results of these analyses with that of the microstratigraphy, it is hoped that a clearer understanding of site formation and better explanation of the presence of humans at TPL is achieved.
Here, we present the results of the program to analyse the microstratigraphy, LOI and χ of sediments in TPL. Our geoarchaeological work aims to prove the efficacy of a microstratigraphic approach to understanding the important stratigraphy of the site by reconstructing its ground conditions, clarifying the taphonomic history of the fossils related to the depositional history of the cave, and exploring the potential archaeology within its sediments. By doing so, we try to resolve how past conditions in TPL (sediment, cave, and catchment) affect the interpretation of human presence at the site and explore how this information changes the narrative of Late Pleistocene human evolution and dispersals in the Far East. We focus the analyses on the upper 4 m Late Pleistocene–Holocene sediment sequence exposed in the 7 m-deep excavation inside the cave. This upper sequence was securely dated to between 46 ± 6 ka and 13 ± 3 ka (Freidline et al., 2023) and was where the human fossils TPL1, 2 and 5 were recovered (Demeter et al., 2012, Demeter et al., 2015, Demeter et al., 2017).
And, to make it doubly difficult for creationists to explain without the usual lies and misrepresentations of the dating methods used, the authors have allowed for possible errors by using the minimum ages of the fossils. In other words, if creationists are right about errors in the dating methods, these fossils are even older than creationists dogma says they should be.
And so creationism staggers on under the load of yet more evidence that it is just a childish fairytale.
Friday, 27 September 2024
Refuting Creationism - Tiny Shells Hold a Record of Sea Temperature Changes 10,000 Years Before 'Creation Week'
Ice age clues point to more extreme weather patterns in our future | University of Arizona News
With so much of Earth history occurring before creationism's little god allegedly created a small flat planet with a dome over it in the Middle East, it's useful to be able to recover data on global events such as climate change and sea temperature changes that can be projected into the future to predict what changes we can expect.
The 'El Niño' is a climate phenomenon that has a profound effect on world climate. It occurs every 2-7 years and is characterized by a warming of the sea surface in the central and eastern Pacific Ocean. It changes ocean currents, atmospheric humidity and rainfall, and jet streams that drive weather patterns, so understanding when these events occurred in the past and mapping them onto known climate patterns can help us predict future weather patterns.
Now scientist at the University of Arizona have developed a model for predicting how El Niño affects global weather patterns which needs to be validated against actual data, so they have analyzed the record of sea temperature change recorded in deposits of tiny foraminifera shells in ocean sediment, going back to the last Ice Age, 10,000 years before creationists think Earth existed.
Of course, the reason was not to refute creationism - it does that incidentally - but to provide a longer history on which to base future predictions than are currently available.
Monday, 23 September 2024
Refuting Creationism - Oldest Modern Human DNA Ever Recovered From South Africa - From About The Time Of 'Creation Week'!
Oldest DNA from South Africa decoded to date | Max-Planck-Gesellschaft
Just as creationism's legendary creator god was creating a small flat planet with a dome over it in the Middle East, there were modern humans living (or rather dying) in South Africa.
A team of scientists led by the Max Planck Institute for Evolutionary Anthropology and including palaeoanthropologists from University of Cape Town, Cape Town, South Africa, have now succeeded in reconstructing the genomes from the remains of 13 individuals who died between 1,300 and 10,000 years ago, including the oldest human genome from South Africa to date.
If the creation myth had any element of truth in it, humans would have radiated from the legendary founder couple to form a thriving community living in a rock shelter in South Africa's Cape Province. Moreover, the evidence now shows that these people were isolated from the rest of humanity for many thousands of years.
Tuesday, 10 September 2024
Refuting Creationism - Migration Into Iberia When Creationists Think Earth Was Under A Genocidal Flood
Theory of a violent invasion of the Iberian Peninsula in Late Prehistory now questioned - Universitat Autònoma de Barcelona - UAB Barcelona
Had the ancient inhabitants of the Iberian Peninsula contrived to get their oral history and origin myths written down in the same way that the Bronze Age Canaanite pastoralists did, we might have had a slightly more accurate and less implausible history. It certainly wouldn't have had daft tales about a global genocidal flood just at the time newcomers with new ideas, a new language and new techniques of animal husbandry were migrating into the area having traversed Western Europe from the Steppes of Central Asia.
Unlike the parochial Canaanite nonsense, it might well have had people, places and animals from more than a day or two's walk from the Canaanite Hills.
Archaeological evidence shows that, at the time when creationist superstition says everyone had been drowned in a genocidal, global flood several thousand feet deep, by a vindictive god, people originating on the Steppes of Central Asia were migrating across western Europe and into the Iberian Peninsula, as though nothing unusual was happening.
Monday, 9 September 2024
Malevolent Designer News - What Was The Divine Malevolence Doing With Plague Bacteria 5000 years ago?
Neolithic plague bacterium did not cause mass mortality
What was creationism's divine malevolence up to with one of its most successful pathogens with which if killed hundreds of millions and changes society - the Yersinia pestis bacterium which caused the waves of black death and plague that regularly spread across the world?
It seems to have been experimenting, possibly trying to either perfect its virulence or work out the best delivery system to ensure it got to and killed as many people as possible. Sometimes, entire villages were wiped out. Not far from where I currently live are a couple of former villages that disappeared during the black death - the village of Woodperry near Oxford is an example, surviving now only in the name 'Woodperry Road' and a farmhouse later built on the site.
But 5000 years ago, Y. pestis doesn't seem to have been anything like a virulent as it became in the 12th Century. According to a recent discovery, it was capable of killing the occasional neolithic farmer but not of becoming a major pandemic able to kill hundreds of thousands and depopulate vast areas.
So, what changed, and more to the point, which explanation would a creationist prefer; the one which blames their god or the one which attributes it to evolution, climate change and cultural changes in human society? One thing we can be sure of though is the Michael J. Behe's biologically nonsensical religious apologetic of 'genetic entropy', causing the bacterium to 'devolve' away from an assumed created perfection (as though that were remotely possible), can be ruled out, because whatever the changes were, it led to a massive increase in the number of Y. pestis organisms, so was indisputably beneficial to it - in other words, in classical terms, it evolved.
Thursday, 5 September 2024
Refuting Creationism - How Modern Humans Spread Across Europe Thousands Of Years Before 'Creation Week'
New population model identifies phases of human dispersal across Europe
There are of course, very many things Bible-literalist creationists need to ignore, lie about and/or misrepresent to maintain the delusion of Earth being just a few thousand years old, not the least of which is the abundant geological and archaeological evidence of human activity long before they believe Earth was created by magic out of nothing in the so-called 'Creation Week'.
Their handicap is in trying to compress the entire 13.8 billion year history of the Universe, the 3.8 billion year history of planet Earth and the 2-3 million year history of human evolution, into 10,000 or fewer years, and then trying to ignore the evidence of continuous, unbroken cultural history extending from way before a global genocidal flood, right through it and continuing to modern times, as though such a flood never happened.
And, as is normal with science, a paper just published in Nature Communications, gives them more evidence to ignore, lie about and/or misrepresent. It shows the history of early modern human migration across Europe during the Aurignacian (43,000 -32,000 years ago). The research comes from a team from the University of Cologne, Germany, led by Professor Dr Yaping Shao. It is explained in a University of Cologne press release:
Tuesday, 3 September 2024
Fine-Tuned Fallacy Exposed - How Earth's Ecosystems Caused Multiple Mass Extinctions Between 185 And 85 Million Years Before 'Creation Week'
Land-sea tag-team devastated ocean life millions of years ago reveal scientists | University of Southampton
It can only be by remaining wilfully ignorant of the history of life on Earth and how it has been affected by catastrohic changes, that creationists are able to maintain the childish delusion that Earth is somehow fine-tuned for life, and especially their life.
The fact that very much of the surface of Earth, such as oceans, deserts and high mountain ranges is lethal without special equipment, and without cloths, shelter and fire , most of the northern and southern latitudes are not survivable in an average winter should be a clue to the fallacy of the claim, but then, from the safety of small town, Bible Belt America, where the rest of the world might as well not exist, such places can be safely ignored.
But the fact remains, whether ignored or not, that there have been several periods in the history of life on Earth that the planet has become a very hostile place, resulting in mass extinctions wheree life looked as though someone had hit the reset button. The primary cause of these fluctuations is almost certinly plate techtonics which, through mid-ocean ridge activity, release sulphates and phosphates which produce blooms of plankton which then die, locking up carbon and producing anoxic sediments on the ocean bed, and by releasing CO2 into the atmosphere where if causes a rise in ocean temperature.
Volcanic activity also produces basalt which, when eroded and washed into the sea adds to the phosphates which produce planktonic blooms and subsequent deoxygenation.
How these terrestrial and marine sources act together to produce the frequent OAEs has now been explained.
Saturday, 31 August 2024
Creationism Refuted - What a Mallorcan Cave Tells Us Of Events Before 'Creation Week'.
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.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.
Key Information About Genovesa Cave
Implications for Understanding Sea-Level Changes
- 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.
- 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).
- 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.
- 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.
- 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.
- 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
- 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.
- 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?
- 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.
- 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.
- 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
- 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.
- 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.
- 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.
- 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
- 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.
- 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.
- 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
- "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.
- "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.
- "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.
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
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.
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.
AbstractBecause Creationists love to find fault with the geochronology in these records of pre-'Creation Week' events, I've included sections on geochronology here:
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 publications6,7,8,9,10,11 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 activity7,8. 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 unreliable1,8,13.
Several studies have reevaluated most of the previously dated materials and supplemented them with new radiocarbon dates obtained from charcoal, ash, and bones6,7,9,10. 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 literature7,8,14.
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 decades8,15,16. 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 discovered18,19. The bridge structure was inferred to have been built around the same period20.
Fig. 1: Cave and sample locations.
Fig. 2: Positional relationship between the bridge, preindustrial sea level, and analyzed samples.
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.
Results and discussionLots 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.
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 timescales21,29. 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. 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)
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.