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dmaestro 30-Aug-25, 10:04	Origin of Life www.livescience.com www.yahoo.com
apatzer 30-Aug-25, 10:45	Deleted by apatzer on 30-Aug-25, 10:46.
apatzer 30-Aug-25, 10:48	Sorry typos Interesting article, but I respectfully disagree. The claim that early Earth was a barren wasteland incapable of supporting life until a massive protoplanet collision brought in the necessary ingredients is inaccurate. Volatiles, including water, are found even on Mercury today. These substances often become chemically bound within rocks. Our entire solar system formed from the same protoplanetary disc, which was enriched by dozens of supernovae. Similarly, the majority of Earth's water was not delivered by impacts alone; most was chemically bound within the rocky material from which Earth formed. For instance, common rocks can contain up to about 20% water by weight, which is only released upon heating. Factors such as the Late Heavy Bombardment, Earth's biosphere, gravity, subduction cycles, continental movement, and plate tectonics all contributed to shaping Earth's habitability. While I acknowledge that the giant impactor Theia contributed material to Earth, its greatest significance to life lies in how it added iron to Earth's core, enabling the generation of our magnetic field. The impact also created the proto-lunar disc, leading to our oversized Moon, which stabilized Earth's axial tilt and rotational speed. The Moon's close proximity generated powerful tidal forces—tides measured in miles—that helped wash nutrients onto land. As the Moon gradually moved away, it helped stabilize these conditions, supporting the development of life.
softaire 30-Aug-25, 11:38	Thanks to DM for original interesting articles. Thanks to Apatzer for for very interesting reply and rebuttal. For my part, I think both ideas could be correct, or partially correct. Whatever the case may be for how life originated here, I'd like to thrown in another consideration. It may well be that there is (somehow) one LUCA (Last Universal Common Ancestor) that all live has diversified from and has become spread around the world in so many different species. But what remains unanswered in this theory is how did life split into two such different forms as "Vegetation" and "Animal" life. Vegetation uses the energy of the Sun (photosynthesis) to generate life. Animal life consumes the energy from other life to generate life. Where did these two radically different forms of life get the idea to use the Sun as an energy source or to steal the energy from other life as the energy source? When did that happen? Did the split happen after the LUCA appeared? Or, did there arrive here TWO LUCA's... one for vegetation and one for animal life?
dmaestro 30-Aug-25, 12:37	I don’t think what Patz says is excluded nor do I disagree. I think it’s correct that Theia was a critical part of a larger process going back to the origin of this universe, one as a whole that made life possible. As Patz says remnants of Theia are still seen in the core and the creation of the Moon. And both proto Earth and Theia arose from a proto solar system. Softaire: Plants and animals are both Eukaryotes. Eukaryotes are organisms and cells that contain a membrane-bound nucleus and other specialized membrane-bound organelles, such as mitochondria and endoplasmic reticulum. These cellular features allow for compartmentalization and complex functions, distinguishing them from simpler prokaryotic cells. Eukaryotic organisms include all animals, plants, fungi, and protists, forming complex multicellular bodies and some single-celled life forms. It’s believed they resulted from fortunate union of prokaryotic cells. Plants include chloroplasts for energy while animals just have mitochondria for energy. It’s suspected mitochondria arose from prokaryotic cells who primarily used therma sources for energy. We know that thermal sources and available minerals produce chemical reactions also needed for life. LUCA is the first life that survived—virus are not fully all alive. The use of ATP as energy storage is its innovation.
apatzer 30-Aug-25, 13:13	Thank you softaire and dmaestro for the great discussion and ideas. I think my original post was a little too limited in thought. (After reading both of your replies) Both of you are teaching me to see things in a different way or things that I wouldn't have thought of. So thank you both! When I have more time I'm going to re read both of your replies again and perhaps respond.
dmaestro 31-Aug-25, 06:49	www.popularmechanics.com
dmaestro 31-Aug-25, 07:13	www.sciencedirect.com Cyanobacteria arising over 3.5 M years ago produced the free oxygen needed for future animals. True plants are eukaryotes believed to be the result pf symbiotic cellular union incorporating Cyanobacteria and their chloroplasts.
softaire 31-Aug-25, 07:19	Plant and animal split from LUCA It seems that there was only one LUCA and we DO get everything from it. Plants and animals split from it about 1.2 to 1.6 billion years ago. That was a long time ago, but life forming was much longer ago than that. I find it amazing how long the timelines are for anything to really happen with life. But once it did, life diversified exponentially and very rapidly (comparatively). Anybody know what the trigger was? ....................................................... ### 🧬 LUCA: The Last Universal Common Ancestor LUCA is the hypothetical ancestor of all current life on Earth. It likely lived around **3.5 to 4 billion years ago**, possibly in hydrothermal vent environments. LUCA gave rise to the three domains of life: - **Bacteria** - **Archaea** - **Eukarya** (which includes animals, plants, fungi, and protists) ### 🌿🐾 The Split Between Animal and Plant Life Animals and plants are both part of the **Eukarya** domain. But they didn’t split directly from LUCA—they diverged much later, after the emergence of eukaryotic cells. Here’s a rough timeline: | Event | Approximate Timeframe | Notes | |------|------------------------|-------| | LUCA | ~3.5–4 billion years ago | Common ancestor of all life | | First Eukaryotes | ~2 billion years ago | Cells with nuclei and organelles emerge | | Divergence of Plants & Animals | ~1.6–1.2 billion years ago | Likely from a common unicellular ancestor within Eukarya | So, the **animal-plant split** occurred **about 1.2 to 1.6 billion years ago**, long after LUCA. It was part of the diversification of eukaryotic lineages, possibly from a protist-like ancestor.
dmaestro 31-Aug-25, 08:34	news.stanford.edu The Cambrian Explosion.
apatzer 31-Aug-25, 08:57	dmaestro I’d like to propose a hypothesis regarding the Cambrian explosion. I suggest that a nearby superluminous supernova—or possibly a hypernova triggered by a millisecond pulsar pair collision, within 1,000 light-years from Earth. An event like this may have produced an extremely intense but brief radiation event. Such an occurrence could have eradicated a large percentage of surface life, perhaps around 80%.. in essence it's a super luminous burst of mixed radiation/particles. This IMHO would be very similar to the phenomenon observed after a nuclear detonation, where rapid biological regrowth occurs even near ground zero, this event may have triggered a surge of recovery. In particular, it could have fueled explosive growth in algae and plankton, alongside widespread genetic mutations across surviving species. This combination of mass die-off, accelerated regrowth, and increased mutation rates might have set the stage for the dramatic diversification of life known as the Cambrian explosion. How this ties into the article you posted on increased oxygen levels. an intense radiation event like a nearby supernova could potentially affect oxygen-producing microorganisms such as algae and cyanobacteria in complex ways. Experimental studies show that ionizing radiation can impact the photosynthetic activity of microorganisms, sometimes inhibiting growth but also in certain conditions enhancing the oxygen evolution capacity after exposure. Radiation can induce stress that might stimulate adaptive responses, including rapid regrowth or increased photosynthetic efficiency under some light conditions. Thus, a brief but powerful radiation pulse could theoretically cause mass die-off while also triggering regrowth and mutation in oxygen-producing microbes. This could lead to an increase in oxygen production, especially if surviving populations rapidly expand after the event. However, the exact outcome would depend heavily on the radiation dose, duration, environmental factors, and microbial species involved. Of course, this remains only a hypothesis.
softaire 31-Aug-25, 09:01	I can believe that an increase in oxygen was responsible for the increase in diversity of life.

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