Friday 12 May 2023

Creationism in Crisis - Not a Founder Couple, Not Even a Founder Species!

Slideshow code developed in collaboration with ChatGPT3 at https://chat.openai.com/

Reconstruction of Neanderthal woman

Photo: Bacon Cph; makeup: Morton Jacobsen
https://doi.org/10.1371/journal.pbio.0020449.g001
Nose shape gene inherited from Neanderthals - UCL News

One of the associated dogmas of creationism, with its slavish adherence to Bible literalism, is the legend of Adam & Eve as a single founder couple of the human species without ancestors, together with a genocidal flood 4000 years ago in which the human population was reduced to just eight octogenarians who were the incestuous ancestors of all living humans.

In order to sustain that belief, creationists need to ignore all the evidence that shows several lines of uninterrupted mitochondrial DNA (female) history going back hundreds of thousands of years and several uninterrupted lines of Y chromosome (male) history.

This same genetic evidence also shows that the last common female ancestor and the last common male ancestor of all living humans could not even have lived contemporaneously, let alone met and committed the 'original sin' that we are all supposedly guilty of and need the vicarious redemption by the blood sacrifice of an innocent person to be saved from being punished for by an invisible, mind-reading sky man.

Another major problem for creationists is the evidence that non-African Homo sapiens all carry evidence not only that there never was a severe bottleneck in evolutionary history but that we interbred with at least two other hominin species, especially Neanderthals, so that non-African humans carry something like 1-4% Neanderthal DNA.

Some paleoanthropologists have even suggested that Neanderthals never died out but were simply absorbed into the growing Eurasian Homo sapiens population to the extent that there is now more Neanderthal DNA in the human population than there ever was in the total Neanderthal population.

So, not only not a founding couple who could have committed the original sin, but not even a single founding species!

The evidence of Neanderthal DNA introgression into the genome of Homo sapiens comes from various scientific studies, particularly those involving the analysis of ancient and modern DNA. Here are some key references that support this idea:
  1. Green, R. E. et al. (2010). "A Draft Sequence of the Neanderthal Genome." Science, 328(5979), 710-722. doi: 10.1126/science.1188021
    This groundbreaking study presented the first draft sequence of the Neanderthal genome, revealing that modern humans share genetic material with Neanderthals.
  2. Prüfer, K. et al. (2014). "The complete genome sequence of a Neanderthal from the Altai Mountains." Nature, 505(7481), 43-49. doi: 10.1038/nature12886
    This study sequenced the entire genome of a Neanderthal individual from the Altai Mountains, providing further evidence of genetic admixture between Neanderthals and modern humans.
  3. Sankararaman, S. et al. (2014). "The genomic landscape of Neanderthal ancestry in present-day humans." Nature, 507(7492), 354-357. doi: 10.1038/nature12961
    This research investigated the extent and distribution of Neanderthal DNA in the genomes of present-day humans, identifying regions of the genome where Neanderthal ancestry is present.
  4. Vernot, B. & Akey, J. M. (2015). "Resurrecting Surviving Neandertal Lineages from Modern Human Genomes." Science, 343(6174), 1017-1021. doi: 10.1126/science.1245938
    This study used statistical methods to identify segments of Neanderthal DNA that are present in the genomes of modern humans, providing insights into the specific genetic contributions from Neanderthals.
  5. Simonti, C. N. et al. (2016). "The phenotypic legacy of admixture between modern humans and Neandertals." Science, 351(6274), 737-741. doi: 10.1126/science.aad2149
    This study explored the phenotypic effects of Neanderthal DNA introgression, linking specific Neanderthal genetic variants to various traits in modern humans.

These references represent just a few of the many studies conducted on the topic. The field of ancient DNA and human evolution is rapidly evolving, and further research continues to shed light on the extent and implications of Neanderthal DNA admixture.

chatGPT3 "Evidence of Neanderthal DNA ingression into Homo sapiens genome, with references, please." [Response to user question]
Retrieved from https://chat.openai.com/]
This evidence was reinforced a few days ago when a large research team led by Dr Kaustubh Adhikari, University College London (UCL) Genetics, Evolution & Environment, and The Open University, published a paper in Communications biology, in which they announced the discovery of a Neanderthal gene in modern Europeans which controls the size of the nose.

Larger noses allow the air to be warmed up more efficiently than smaller noses. Neanderthals had evolved to live in Eurasia during the Ice Age, so, when the gene for a large nose was inherited by early modern H. sapiens, it conveyed a significant advantage in the colder north, so spread quickly through the gene pool in classic Darwinian evolution by natural selection.

The UCL news release explains the research and the main findings:
The new Communications Biology study finds that a particular gene, which leads to a taller nose (from top to bottom), may have been the product of natural selection as ancient humans adapted to colder climates after leaving Africa.

In the last 15 years, since the Neanderthal genome has been sequenced, we have been able to learn that our own ancestors apparently interbred with Neanderthals, leaving us with little bits of their DNA. Here, we find that some DNA inherited from Neanderthals influences the shape of our faces. This could have been helpful to our ancestors, as it has been passed down for thousands of generations.

Dr Kaustubh Adhikari, Co-corresponding author
UCL Genetics, Evolution & Environment
And The Open University) said:
The study used data from more than 6,000 volunteers across Latin America, of mixed European, Native American and African ancestry, who are part of the UCL-led CANDELA study, which recruited from Brazil, Colombia, Chile, Mexico and Peru. The researchers compared genetic information from the participants to photographs of their faces – specifically looking at distances between points on their faces, such as the tip of the nose or the edge of the lips – to see how different facial traits were associated with the presence of different genetic markers.

The researchers newly identified 33 genome regions associated with face shape, 26 of which they were able to replicate in comparisons with data from other ethnicities using participants in east Asia, Europe, or Africa.

In one genome region in particular, called ATF3, the researchers found that many people in their study with Native American ancestry (as well as others with east Asian ancestry from another cohort) had genetic material in this gene that was inherited from the Neanderthals, contributing to increased nasal height. They also found that this gene region has signs of natural selection, suggesting that it conferred an advantage for those carrying the genetic material.

It has long been speculated that the shape of our noses is determined by natural selection; as our noses can help us to regulate the temperature and humidity of the air we breathe in, different shaped noses may be better suited to different climates that our ancestors lived in. The gene we have identified here may have been inherited from Neanderthals to help humans adapt to colder climates as our ancestors moved out of Africa.

Dr Qing Li, First author
School of Life Sciences and Human Phenome Institute
Fudan University
Yangpu District, Shanghai, China

Most genetic studies of human diversity have investigated the genes of Europeans; our study’s diverse sample of Latin American participants broadens the reach of genetic study findings, helping us to better understand the genetics of all humans.

Professor Andres Ruiz-Linares, Co-corresponding author
School of Life Sciences and Human Phenome Institute
Fudan University, Yangpu District, Shanghai, China
Aix-Marseille Université, Marseille, France.
Department of Genetics, Evolution and Environment, and UCL Genetics Institute,
University College London, London, UK.
The finding is the second discovery of DNA from archaic humans, distinct from Homo sapiens, affecting our face shape. The same team discovered in a 2021 paper that a gene influencing lip shape was inherited from the ancient Denisovans.

The study involved researchers based in the UK, China, France, Argentina, Chile, Peru, Colombia, Mexico, Germany, and Brazil.
In the abstract to their paper, the scientists say:
Abstract

We report a genome-wide association study of facial features in >6000 Latin Americans based on automatic landmarking of 2D portraits and testing for association with inter-landmark distances. We detected significant associations (P-value <5 × 10−8) at 42 genome regions, nine of which have been previously reported. In follow-up analyses, 26 of the 33 novel regions replicate in East Asians, Europeans, or Africans, and one mouse homologous region influences craniofacial morphology in mice. The novel region in 1q32.3 shows introgression from Neanderthals and we find that the introgressed tract increases nasal height (consistent with the differentiation between Neanderthals and modern humans). Novel regions include candidate genes and genome regulatory elements previously implicated in craniofacial development, and show preferential transcription in cranial neural crest cells. The automated approach used here should simplify the collection of large study samples from across the world, facilitating a cosmopolitan characterization of the genetics of facial features.

The fact that another piece of research refutes both creationism and the fundamental notion in Christianity - the need for redemption because of the 'original sin' of our collective remote ancestor, hence the morally reprehensible notion that vicarious redemption can come from a blood sacrifice of an innocent humans being - is almost taken for granted these days.

But what religious leader is ever going to admit that the foundation of their faith has been proven false by science, and risk the jobs, income and power over people that declaring us to be sick and selling us the 'cure' has provided them with for centuries?

The whole edifice began to crumble the day the first scientists decided to be led by real-world evidence rather than the ancient ancestral myths for no better reason than their parents told them they were true. It's now reduced mostly to rubble in most civilized countries.


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