Video: Paul Davies on the Origins of Life


2 comments:

  1. I came across an interesting article today on the site NaturalNews.com about some new research i thought you might be interested in reading, entitled:

    “BOMBSHELL: “Consensus” theory of evolution of the species falls apart; new mitochondrial DNA study reveals NO animal species more than 200,000 years old”

    https://www.naturalnews.com/2018-06-10-bombshell-consensus-theory-of-evolution-of-the-species-falls-apart-new-mitochondrial-dna.html

    And you can read the paper here if your so inclined:

    http://www.pontecorboli.com/digital/he_archive_articles/he122018/1_Stockle_Thaler.pdf

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    1. The "bombshell" part does not come from the referenced study - but rather it comes from naturalnews.com (a website with a history of publishing pseudo-scientific nonsense)

      It appears they may have misinterpreted the study they referred to.

      I'm no expert but reading the paper itself suggests something more like 200,000 years since the most recent common ancestor (specifically in terms of mitochondrial DNA, which we only inherit from our mothers. Note that mtDNA is distinct from nuclear DNA - and this difference is important here - no one is saying that all of our DNA is less than 200,000 years old!). This is also consistent with previous studies which speak of "Mitochondrial Eve", dating to roughly 100,000 - 200,000 years ago.

      "In human genetics, the Mitochondrial Eve (also mt-Eve, mt-MRCA) is the matrilineal most recent common ancestor (MRCA) of all currently living humans, i.e., the most recent woman from whom all living humans descend in an unbroken line purely through their mothers, and through the mothers of those mothers, back until all lines converge on one woman."
      https://en.wikipedia.org/wiki/Mitochondrial_Eve

      If so, none of this suggests either that (a) no animal species is older than this, or (b) that somehow evolution "falls apart".

      May I respectfully suggest you get your "news" (especially regarding science) from a more reliable source in future. ;)

      Here is the same study on phys.org:
      https://phys.org/news/2018-05-special-humanity-tiny-dna-differences.html

      Note this section:
      "While asteroids and ice ages have played major roles in evolutionary history, scientists speculate that another great driver may have been the microbial world, notably viruses, which periodically cull populations, leaving behind only those able to survive the deadly challenge.

      "Life is fragile, susceptible to reductions in population from ice ages and other forms of environmental change, infections, predation, competition from other species and for limited resources, and interactions among these forces," says Dr. Thaler. Adds Dr. Thaler, "The similar sequence variation in many species suggests that all of animal life experiences pulses of growth and stasis or near extinction on similar time scales."

      "Scholars have previously argued that 99% of all animal species that ever lived are now extinct. Our work suggests that most species of animals alive today are like humans, descendants of ancestors who emerged from small populations possibly with near-extinction events within the last few hundred thousand years."

      I think this confirms that the study suggests genetic bottlenecks due to relatively recent speciation from earlier lineages that have since gone extinct.

      The phys.org article finishes with this quote from one of the study authors:

      ""It would be very exciting if over the next few years physical anthropologists and others were able to compare mitochondrial DNA from hominid species over the last 500,000 years," says Dr. Stoeckle."

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