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Oldest known multicellulars are Ediacaran seaweed 555 mya

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Chinggiskhaania bifurcata/U Wisconsin-Milwaukee

From ScienceDaily:

Their age is estimated to be more than 555 million years old, placing the fossils in the last part of Precambrian times, called the Ediacaran Period. They provide a crucial view of Earth’s earliest evolution of multicellular life, which scientists now think started millions of years earlier than previously thought.

Scientists think that an explosion of animal diversity and complexity began near the start of the Cambrian Period, about 541 million years ago. But Dornbos said this fossil find is the latest example of multicellular life forms appearing in the preceding Ediacaran Period. More. Paper. (public access)

As the authors say, this helps us understand more about the history of life. What they don’t say is that it narrows the time frame for the whole thing to have just sort of happened.

Further study will likely provide much more information without providing much support for current theory.

See also: The metallome: New origin of life hopeful. If only life didn’t need to be alive, it would all be so much simpler.

and

What we know and don’t, know about the origin of life

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2 Replies to “Oldest known multicellulars are Ediacaran seaweed 555 mya

  1. 1
    awstar says:

    As the authors say, this helps us understand more about the history of life. What they don’t say is that it narrows the time frame for the whole thing to have just sort of happened.

    Real science will eventually narrow the time frame down to a few days for the whole thing to have just sort of happened. And then they will continue to deny it was intelligence that caused it all.

    But then, the one who was there at the beginning already had written the history down for our understanding and warned us that this denial would happen.

  2. 2
    Elshamah says:

    Unicellular and multicellular Organisms are best explained through design

    http://reasonandscience.heaven.....ugh-design

    Proponents of evolution claim like a mantra, that micro evolution leads to macro evolution, and no barrier exists which hinders the transition from one to the other, which last not least explains our biodiversity today.

    The emergence of multicellularity was supposedly, a major evolutionary leap. Indeed, most biologists consider it one of the most significant transitions in the evolutionary history of Earth’s inhabitants. “How a single cell made the leap to a complex organism is however one of life’s great mysteries.”

    Macro evolutionary scenarios and changes include major transitions , that is from LUCA, the last common universal ancestor, to the congregation to yield the first prokaryotic cells, the associations of prokaryotic cells to create eukaryotic cells with organelles such as chloroplasts and mitochondria, and the establishment of cooperative societies composed of discrete multi-cellular individuals. Or in other words : The current hierarchical organization of life reflects a series of transitions in the units of evolution, such as from genes to chromosomes, from prokaryotic to eukaryotic cells, from unicellular to multi cellular individuals, and from multi-cellular organisms to societies. Each of these steps requires the overcome of huge hurdles and increase of complexity , which can only be appreciated by the ones, that have spend time to educate themselves, and gained insight of the extraordinarily complex and manifold mechanisms involved. The emergence of multi-cellularity was ostensibly a major evolutionary leap.

    The switch from single-celled organisms to ones made up of many cells have supposedly evolved independently more than two dozen times. Evolution requires more than a mere augmentation of an existing system for co-ordinated multicellularity to evolve; it requires the ex nihilo creation of an entirely new system of organisation to co-ordinate cells appropriately to form a multicellular individual.

    There is a level of structure found only in multi-cellular organisms: intercellular co-ordination. The organism has strategies for arranging and differentiating its cells for survival and reproduction. With this comes a communication network between the cells that regulates the positioning and abundance of each cell type for the benefit of the whole organism. A fundamental part of this organisation is cellular differentiation, which is ubiquitous in multicellular organisms. This level cannot be explained by the sum of the parts, cells, and requires co-ordination from an organisational level above what exists in individual cells. There is a 4-level hierarchy of control in multicellular organisms that constitutes a gene regulatory network. This gene regulatory network is essential for the development of the single cell zygote into a full-fledged multicellular individual.

    If evolution and transition from unicellular to multi cellular life is exceedingly complex, the chance that it happened once is also exceedingly small. That it happened multiple times separately, becomes even more remotely possible. Convergent evolution of similar traits is evidence against , not for evolution. In order to infer that a proposition is true, these nuances are important to observed. The key is in the details. As Behe states : In order to say that some function is understood, every relevant step in the process must be elucidated. The relevant steps in biological processes occur ultimately at the molecular level, so a satisfactory explanation of a biological phenomenon such as the de novo make of cell communication and cell junction proteins essential for multi-cellular life must include a molecular explanation.

    The cells had not only to hold together, but important mechanisms to stick the cells together had to emerge, that is, the ability of individual cells to associate in precise patterns to form tissues, organs, and organ systems requires that individual cells be able to recognize, adhere to, and communicate with each other.

    Of all the social interactions between cells in a multicellular organism, the most fundamental are those that hold the cells together. The apparatus of cell junctions and the extracellular matrix is critical for every aspect of the organization, function, and dynamics of multicellular structures. Animal cells use specialized adhesion receptors to attach to one another. Many of these adhesion proteins are transmembrane proteins, which means the extracellular portion of these proteins can interact with the extracellular portion of similar proteins on the surface of a neighboring cell. Although diagrams of adhesive structures may suggest that they are static once assembled, they are anything but. Cells can dynamically assemble and disassemble adhesions in response to a variety of events. This seems to be a essential requirement for function right from the beginning of multicellularity. Many adhesion proteins are continuously recycled: Protein at the cell surface is internalized by endocytosis, and new protein is deposited at the surface via exocytosis. The molecular machines to exercise these functions therefore had to emerge together with adhesion proteins. Furthermore, cell adhesion is coordinated with other major processes, including

    1.cell signaling,
    2.cell movement,
    3.cell proliferation, and
    4.cell survival.

    We now know that cell-cell adhesion receptors fall into a relatively small number of classes. They include

    1.immunoglobulin superfamily (IgSF) proteins,
    2.cadherins,
    3.selectins, and, in a few cases,
    4.integrins

    In order to explain multicellularity, its origin must be explained .

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