How Neanderthals, Dinosaurs Disappeared?

IS THE SAME FUNDAMENTAL MECHANISM AT PLAY?

Dinosaurs are still around: they are called birds. Birds are those dinosaurs which enjoyed high metabolism. In difficult circumstances, those who acted quick could stay warm, and make the slow, or their eggs, into lunch. Mammals, too, and probably even more, exerted deadly pressure on dinosaur reproduction.

Dinosaurs were big (the smallest, like Velociraptors, were feather covered, and turkey sized). To create the same number of average individuals dinosaurs may have required a thousand times more energy as for the average bird: obvioulsy after a disaster, their population would not rebound as fast.

The Past Is Printed With DNA, & We Can Read It.

The Past Is Printed With DNA, & We Can Read It.

[As we can read DNA like a printed book, Paleontology is becoming history, complete with written documents! Represented above: the 40,000 years old Homo Sapiens jaw which was sequenced, and found to be a Sapiens Sapiens- Sapiens Neanderthal hybrid.]

Much spectacular progress is made in paleontology, every month. In the latest, some dinosaur protein would have been isolated. Sequencing and making a Jurassic Park, someday, is not science fiction anymore. Such was the truth, in June 2015. (In the preceding month, that would have sounded like science-fiction.)

Now we have a new fact supporting the theory I hold that Neanderthal’s traits were outbred. Here is yesterday’s recap from Nature:

http://www.nature.com/news/europe-s-first-humans-what-scientists-do-and-don-t-know-1.17815

Neanderthals are also still around. Or more exactly Neanderthal genome: 1% to 3% (although some claim up to 9% of combined Neanderthal and Denisovan ancestry!). And more so in East Asia and among Native Americans. Some find strange that Neanderthal genome disappeared more in Europe, where Neanderthal reigned so long.

But it just means that genetic competition between Sapiens Neanderthal and Sapiens Sapiens traits was more in favor of the later there… Perhaps simply because winters are milder in Europe.

Neanderthals had evolved from Archaic Homo Sapiens, and ruled Europe for 300,000 years. Most of the time, the continent was in the grip of glaciation. Neanderthals evolved genetic adaptations to these Arctic conditions, such as a larger body mass, and a more compact, more muscular, powerful body.

However technological advances such as clothing, burning coal (!), the propeller (to launch javelins further), and the bow made those Neanderthal genetic modifications obsolete, moot, duplicative. A prime defect was higher mass. Reproducing the same number of Neanderthals required more energy than the same number of more gracile forms of Homo Sapiens.

When in competition, the reproductive advantage of the more gracile traits grow exponentially in time:
https://patriceayme.wordpress.com/2013/03/14/why-did-neanderthals-disappear/

It is not about Homo Sapiens Sapiens enjoying superior traits relative to Neanderthals.

The disappearance of Neanderthals is about most Sapiens Neanderthal traits having become excess evolutionary baggage. So the traits got out-selected. One should expect that the heavy, Arctic genetic traits were weeded out, and only superior traits (the 3%) were kept. As observed. And more so in Europe, as winters are milder there than in the rest of the Eurasian land mass (South Asia excluded). As observed. In other words, after an Arctic excursion, Neanderthals transmutated back into what they came from, keeping some useful mutations (many having to do with skin).

The tree of evolution is rather a network (with a non-trivial topology).

A case in point is Homo itself. The first prototypes (so to speak) may have separated from chimpanzee like ancestors, ten million years ago. But the official theory has it, at this point, that there was some interbreeding with chimpanzees, around six million years ago again.

BTW, it is not true that no Neanderthal DNA is found in sub-Saharan Africa. That’s so yesteryear, 2014. Neanderthal DNA has been found all the way down to South Africa’s tip (2015 discovery), and the migration route traced.

Patrice Ayme’

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10 Responses to “How Neanderthals, Dinosaurs Disappeared?”

  1. ianmillerblog Says:

    Two other hypotheses I have seen re the Neanderthals is that they were ambush hunters, and as the forests thinned out, they were not suited to the faster movement needed. Also, they tended to live in very small groups (an advantage when food is scarcer) but the sapiens lived in larger groups, and thus were better adapted to hunting in the more open spas, where they could herd the larger animals and kill by attrition.

    The extinction of the raptors is of more interest because they were smaller. My guess is another complicating feature applied.

    • Patrice Ayme Says:

      I have mentioned totally insane and very recent theories of Neanderthals disappearance. They were not smart (of course!). They had no social skills (the group thing). They could not speak…
      But the best was:
      their eyes were too big!
      I have a link at the beginning of:
      https://patriceayme.wordpress.com/2013/03/14/why-did-neanderthals-disappear/

      The beauty of my own theory is that it requires nothing fancy. It’s sort of an automatic, default theory of extinction of traits.

      In the case of Velociraptors, my theory, just based on mass, fails. However, the DIFFERENTIAL reproduction rate is all what is needed. Mesotherms (such as all dinosaurs) would reproduce sluggishly, at best, relative to high metabolism birds and mammals. Animals such as saurian, turtle and snakes can very well not eat for months, so they survived.

      So the extinction through differential reproduction theory depends only upon a sudden differential in energy procurement (from food availability, and, or, fluctuating temperatures, etc.). The 1,000+ dinosaurs species were TOO economically disadvantaged. The 10,000 bird species were not.

  2. John Rogers Says:

    OK, I’m slightly confused. Taking your advice (The simplest questions etc,) when you say “javelin propeller”, do you mean something like an atlatl or spear-thrower?

    • Patrice Ayme Says:

      Yes, indeed. Three words for the same thing. It was thought to have been replaced by the bow. But now 80,000 year old bows have been found, and my guess is that throwing a lance is sometimes more effective than just an arrow… The old ways of hunting have been lost (even in South Africa, where they were practiced very recently…)

  3. Blackbutt Says:

    Blackbutt to Tyranosopher

    On the off-chance someone is interested: In 2010 the H. neanderthalensis genome was mapped and geneticists using sufficient intact DNA from fossils were able to make a broad comparison between it and modern H. sapiens DNA.

    Results showed that the DNA from the modern populations from the Middle East and Europe contained 1 to 4% of H. neanderthalensis components, which isn’t a large proportion but is significant.
    Geneticists then extracted DNA from H. denisova which showed up to 6% of modern Melanesian and Australian Aboriginal DNA is Densovian DNA.

    At this stage, therefore, the “Interbreeding Theory” is looking more plausible.

    In a 2009 paper one conclusion was:
    “We find extensive sharing of putative selection signals between genetically similar populations, and limited sharing between genetically distant ones. In particular, Europe, the Middle East, and Central Asia show strikingly similar patterns of putative selection signals.”
    “A number of interesting patterns emerge from Figure 1. First, there is extensive sharing of extreme iHS and XP-EHH signals between Europe, the Middle East, and Central Asia, while overlap between other regions is much more limited. In fact, 44% of the genomic segments in the 1% tail of iHS in Europe fall in the 5% tail for both the Middle East and Central Asia (89% are shared between Europe and at least one of these two), while only 12% of European signals are present in East Asia by the same criterion.”

    As every animal species that has evolved from a common ancestor e.g. horses and donkeys, were for a considerable time span just two populations of the same species that eventually differentiated, so biological reality is not black and white and perhaps 50,000 years ago Homo sapiens, H. neanderthalensis and H. denisova were in that transition zone. Evidence to hand suggests that H. soloensis went around 50,000 years ago; H. denisova not long after; H. neanderthalensis roughly 30,000 years ago and H. floriensis about 12,000 years ago, leaving this diverse animal, H. sapiens, some suspect due to its superior ability to employ complex language and “imagine”!

    It is important to remember that all humans are products of intermingling and migrations over thousands of years.

    • Patrice Ayme Says:

      Indeed. The tree of evolution is rather a network.

      The theory as explained in:
      https://patriceayme.wordpress.com/2013/03/14/why-did-neanderthals-disappear/
      is not about Homo Sapiens Sapiens enjoying superior traits relative to Neanderthals. It’s about most Neanderthal traits having become excess evolutionary baggage. So the traits got out-selected.

      • John Rogers Says:

        “It’s about most Neanderthal traits having become excess evolutionary baggage. So the traits got out-selected.”

        I think that’s a really good insight.

        • Patrice Ayme Says:

          Thanks, Roger. I am actually going to touch back the essay to make that point a bit clearer…

          Somewhat similarly, the dinosaurs got probably out-selected by their own descent (birds) and the more sophisticated-where-it-mattered mammals. If neither birds nor mammals had existed, without competition at all, dinosaurs and the like may have survived, and have evolved into more cold-friendly variants (as polar dinosaurs have got to have been more cold tolerant!).

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