Since you are not interested in reading the sources offered to you, I see no basis on which we can have a productive conversation.
Best,
Chris
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Is this the paper you are talking about?
De novo gene birth is the process by which new genes evolve from DNA sequences that were ancestrally non-genic. De novo genes represent a subset of novel genes, and may be protein-coding or instead act as RNA genes [[1](https://journals.plos.org/plosgenetics/article?
id=10.1371%2Fjournal.pgen.1008160#pgen.1008160.ref001)]. The processes that govern de novo gene birth ( Fig 1A ) are not well understood, though several models exist that describe possible mechanisms by which de novo gene birth may occur.
Surely you can see why this statement is problematic, right? You just provided a quote that mentions multiple viable models that are further discussed in the paper.
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Flat Earthers donât think a Globe Earth is a reasonable inference at this point. Why should we care about your opinion any more than we care about the opinions of Flat Earthers?
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That is the paper.
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Hi Curtis
I can see this thanks. When I say âviable modelâ I mean one that is predictive and is demonstrated by testing its repeatability. The word model itself can have several meanings as the word evolution does.
How familiar are you with the LTEE literature?
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The mutation and selection model is tested every time there is an attempt to measure a phylogenetic signal in both the morphological and molecular data. The model repeatedly passes that test.
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Iâm not clear on what that means. Might you explain?
sure its possible by changing existing gene for instance.
how a venom will be beneficial in the bee case without a sac or without a hollow spot in the bee stinger?
what do you mean by âexaptionâ?
Same answer as above.
You are calculating the odds of particular outcomes when you compound the probabilities of two function-creating mutations instead of just determining what fraction of all mutations that occur result in functional associations between different genetic elements (quick hint: itâs not the conjunction of the probability of any two function-creating mutations).
Of course you can make anything seem absurd by just making up numbers and declaring that the scenario must conform to your assumptions (such as the idea that the relationship between a hormone and a receptor can only evolve by the conjunction of two de novo function-creating mutations).
so lets take two anatomical examples of the bee and try to explain it stepwise. the first one is the bee eggs (of queen bee) and the hollow part which can lay them. what was the use of the hollow part without the eggs and vice versa ,and what was the use of the bee venom without the venom sac and vice versa?.
First of all, there clearly are no extant descendants of a queen bee that didnât lay eggs. So if there was ever a time before bees evolved stingers, they still laid eggs. Now, of course, bees always had stingers.
Why? Stingers are modified ovipositors, which most insects have which they use to lay eggs.
These naturally secrete numerous liquids that help with all sorts of things. Signaling pheromones, lubrication, waste products. You know, like bodily orifices in anything that is alive generally does. These things contain all sorts of compounds made by cells in the body, including proteins, lipids and so on.
There was never a time at which there was a useless stinger just sitting around. They began as ovipositors. The stinger evolved from ovipositors, in insects without stingers (but with ovipositors), which were still capable of laying eggs with their ovipositors.
They are normally used to stab into the ground (or into tree bark, or many other things) and deposit their eggs. This thing about bending their ovipositors down below them in a stabbing motion is how they normally lay their eggs when they stab into other objects to deposit them. The ovipositor comes in many different forms in different insects. Ranging from something that doesnât at all look even remotely like a stinger, such as this:
Or this:
(From: Green JE, Cavey M, MĂ©dina Caturegli E, Aigouy B, Gompel N, Prudâhomme B. Evolution of Ovipositor Length in Drosophila suzukii Is Driven by Enhanced Cell Size Expansion and Anisotropic Tissue Reorganization. Curr Biol . 2019;29(12):2075-2082.e6. doi:10.1016/j.cub.2019.05.020)
Like, millions of different morphologies, the structure is extremely genetically plastic. It also secretes all sorts of stuff in all of them. Protective mucus for the eggs, lubrication (so the eggs can slide out), stuff with smells to attract mates (or scare off or confuse predators) and so on and so forth. Some of the contents of these secretions turned out to be useful in combat as predators found them repulsive or painful or paralyzing. These evolved into genuine venoms(proteins duplicated and mutated and changed to be more effective as venoms). The ovipositor became a weapon in addition to being a device for laying eggs inside the ground/inside rotting fruits/inside tree bark/inside animal fecal matter/inside living victims.
Got any more irrelevant rabbit holes for us to chase down?
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ok. so this is probably the first step. but what was the use of the eggs without the hollow part in that ovipositor?
What makes you think it was ever not hollow?
New genes are produced by new mutations that are selected for if they produce new beneficial functions. This process should produce a phylogenetic signal in both the morphological and molecular data.
So you have abandoned the snake example?
Exaption is the process of an already existing structure evolving to take on a new function.
I suppose so, but the selected mutations affecting morphology are rare enough that I doubt you would get a signal that would rise above the neutral signal.
If so eggs could always pass through a hollow area? because if this is the case, eggs cant evolve without a hollow part (or a part where they can evolve inside the body) and vice versa.
yep. for the sake of the discussion.
Have you also abandoned the hormone/receptor argument after I showed how it could evolve step by step?