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The family tree of life changes to a molecular tree of life.

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  • The family tree of life changes to a molecular tree of life.

    Some religious critics of evolution try to conclude that recent developments in science greatly changed the family tree and will upend the scientific evolution of life. These changes in the family tree have been in the wind for a while with the advancement of coding DNA more accurately. and establishing the molecular relationships in the branches of the tree of life more accurately fit the other evidence of relationships such as regionally association of evolving species over time. The major flaw in the old system that developed over the past 180 years or more assumed that similar-appearing animals and/or with similar morphology were closely related. IT has been known that widely unrelated animals and plants develop very similar forms and morphologies in adaptation to similar environments, but it was still assumed very similar animals and plants were closely related. The following general article is a good introduction to molecular evolution replacing the older system of classification of relationships in the tree of life.

    This is added evidence that nature and changes in the environment are likely the most important driving force in evolution because the environment and change dictate the forms and morphologies of life. The change is greatest among mammals.

    The concept of the limited number of 'designs' or 'body plans' is addressed a little. Please note: that 'Designs' as used here is not a reference to being designed.

    Source: https://www.sciencealert.com/new-dna-technology-is-shaking-up-the-branches-of-the-evolutionary-tree



    New DNA Technology Is Shaking Up The Branches of The Evolutionary Tree


    MATTHEW WILLS, THE CONVERSATION
    25 JUNE 2022

    If you look different to your close relatives, you may have felt separate from your family. As a child, during particularly stormy fall outs you might have even hoped it was a sign that you were adopted.

    As our new research shows, appearances can be deceptive when it comes to family. New DNA technology is shaking up the family trees of many plants and animals.

    The primates, to which humans belong, were once thought to be close relatives of bats because of some similarities in our skeletons and brains. However, DNA data now places us in a group that includes rodents (rats and mice) and rabbits. Astonishingly, bats turn out to be more closely related to cows, horses, and even rhinoceroses than they are to us.

    Scientists in Darwin's time and through most of the 20th century could only work out the branches of the evolutionary tree of life by looking at the structure and appearance of animals and plants. Life forms were grouped according to similarities thought to have evolved together.

    About three decades ago, scientists started using DNA data to build "molecular trees". Many of the first trees based on DNA data were at odds with the classical ones.

    Sloths and anteaters, armadillos, pangolins (scaly anteaters), and aardvarks were once thought to belong together in a group called edentates ("no teeth"), since they share aspects of their anatomy.

    Molecular trees showed that these traits evolved independently in different branches of the mammal tree. It turns out that aardvarks are more closely related to elephants while pangolins are more closely related to cats and dogs.
    Coming together


    There is another important line of evidence that was familiar to Darwin and his contemporaries. Darwin noted that animals and plants that appeared to share the closest common ancestry were often found close together geographically. The location of species is another strong indicator they are related: species that live near each other are more likely to share a family tree.

    For the first time, our recent paper cross-referenced location, DNA data, and appearance for a range of animals and plants. We looked at evolutionary trees based on appearance or on molecules for 48 groups of animals and plants, including bats, dogs, monkeys, lizards, and pine trees.

    Evolutionary trees based on DNA data were two-thirds more likely to match with the location of the species compared with traditional evolution maps. In other words, previous trees showed several species were related based on appearance.

    Our research showed they were far less likely to live near each other compared to species linked by DNA data.

    It may appear that evolution endlessly invents new solutions, almost without limits. But it has fewer tricks up its sleeve than you might think.

    Animals can look amazingly alike because they have evolved to do a similar job or live in a similar way. Birds, bats and the extinct pterosaurs have, or had, bony wings for flying, but their ancestors all had front legs for walking on the ground instead.

    (Oyston et al., Communication Biology, 2022)

    Above: The color wheels and key indicate where members of each order are found geographically. The molecular tree has these colors grouped together better than the morphological tree, indicating closer agreement of the molecules to biogeography.

    Similar wing shapes and muscles evolved in different groups because the physics of generating thrust and lift in air are always the same. It is much the same with eyes, which may have evolved 40 times in animals, and with only a few basic "designs".

    © Copyright Original Source






    Last edited by shunyadragon; 06-26-2022, 08:54 PM.
    Glendower: I can call spirits from the vasty deep.
    Hotspur: Why, so can I, or so can any man;
    But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

    go with the flow the river knows . . .

    Frank

    I do not know, therefore everything is in pencil.

  • #2
    Given how genetic evidence has been largely trumping morphological evidence for several decades now, I'm actually surprised that it took this long. As you said this change has "been in the wind for a while" and is now long overdue.

    I'm always still in trouble again

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    • #3
      Originally posted by rogue06 View Post
      Given how genetic evidence has been largely trumping morphological evidence for several decades now, I'm actually surprised that it took this long. As you said this change has "been in the wind for a while" and is now long overdue.
      I have followed this for years and yes it was overdue and neglected, but science historically has been dominated by closet people each doing their own thing and not public information oriented. Also most research was focused on the molecular evolution of individual known morphological relationships between primates, sea mammals, and sharks It was not until recently that they brought all that research together including 'shrews' and other neglected mammals.
      Glendower: I can call spirits from the vasty deep.
      Hotspur: Why, so can I, or so can any man;
      But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

      go with the flow the river knows . . .

      Frank

      I do not know, therefore everything is in pencil.

      Comment


      • #4
        Originally posted by rogue06 View Post
        Given how genetic evidence has been largely trumping morphological evidence for several decades now, I'm actually surprised that it took this long. As you said this change has "been in the wind for a while" and is now long overdue.
        Yes, molecular evolution did resolve many problems of the family tree of animals and plants, but the real breakthroughs are and will be on the origin of life and the early evolution of complex animals in the Edicarian including the relationship between viruses and primitive Edicarian life. The molecular clock is an important part of the phylogenetic molecular evolution.

        The molecular phylogenetic tree of life will define the whole history of life from the beginning.

        Source: https://jgs.lyellcollection.org/content/179/4/jgs2021-107



        The Ediacaran origin of Ecdysozoa: integrating fossil and phylogenomic data

        View ORCID ProfileRichard J. Howard, Mattia Giacomelli, View ORCID ProfileJesus Lozano-Fernandez, View ORCID ProfileGregory D. Edgecombe, View ORCID ProfileJames F. Fleming, Reinhardt M. Kristensen, View ORCID ProfileXiaoya Ma, View ORCID ProfileJørgen Olesen, View ORCID ProfileMartin V. Sørensen, Philip F. Thomsen, Matthew A. Wills, Philip C. J. Donoghue and View ORCID ProfileDavide Pisani

        Abstract


        Ecdysozoans (Phyla Arthropoda, Kinorhyncha, Loricifera, Nematoda, Nematomorpha, Onychophora, Priapulida, Tardigrada) are invertebrates bearing a tough, periodically moulted cuticle that predisposes them to exceptional preservation. Ecdysozoans dominate the oldest exceptionally preserved bilaterian animal biotas in the early to mid-Cambrian (c. 520–508 Ma), with possible trace fossils in the latest Ediacaran (<556 Ma). The fossil record of Ecdysozoa is among the best understood of major animal clades and is believed to document their origins and evolutionary history well. Strikingly, however, molecular clock analyses have implied a considerably deeper Precambrian origin for Ecdysozoa, much older than their earliest fossils. Here, using an improved set of fossil calibrations, we performed Bayesian analyses to estimate an evolutionary time-tree for Ecdysozoa, sampling all eight phyla for the first time. Our results recover Scalidophora as the sister group to Nematoida + Panarthropoda (= Cryptovermes nov.) and suggest that the Ediacaran divergence of Ecdysozoa occurred at least 23 myr before the first potential ecdysozoan trace fossils. This finding is impervious to the use of all plausible phylogenies, fossil prior distributions, evolutionary rate models and matrix partitioning strategies. Arthropods exhibit more precision and less incongruence between fossil- and clock-based estimates of clade ages than other ecdysozoan phyla.

        © Copyright Original Source




        Journal of the Geological Society, 179, jgs2021-107, 10 March 2022, https://doi.org/10.1144/jgs2021-107
        Last edited by shunyadragon; 06-28-2022, 10:19 AM.
        Glendower: I can call spirits from the vasty deep.
        Hotspur: Why, so can I, or so can any man;
        But will they come when you do call for them? Shakespeare’s Henry IV, Part 1, Act III:

        go with the flow the river knows . . .

        Frank

        I do not know, therefore everything is in pencil.

        Comment

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