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https://phys.org/news/2022-01-earliest-human-eastern-africa-dated.html?fbclid=IwAR3qOIHmKKO6EsILQUbh6DCngk5MjeQl3pI-ugX_n6yrHc5k-WPp5GhYkEM

Oh boy! Well, if you listen to highly paid newscasters reading and repeating gobbledegook without realizing that is gobbledegook, we might conclude that there is some kind pandemic of incomprehension. Attention-span and critical thought begins to be eroded by a child's environment from the year of language acquisition onward. I get that. I was in no wise blaming him! He's instructing at a level where all the spadework should have been done by many, many instructors from grade school upward. By the time he gets to them, many students are already beyond reach. That's why, in elementary school, teachers used to write comments to the parents regarding their child's progress in various aspects of education and socialization, while the grades were earned on a term-end test of what knowledge has been acquired and retained. (I do think, though, that projects and essays represent a test of the skills thus far acquired, as well as the student's facility in the applications of those skills. So it's not unreasonable to grade the product.) I concur. Wholeheartedly. The inability of the system to deliver that kind of instruction - despite the heroic efforts of excellent teachers - involves a whole web of related societal problems. I do also agree with the need for unbiased assessment. OK. I recognize that you plagiarized Newton without citation or recognition.

This does push back the age that can confidently be attributed to homo sapiens, although there are other finds that are now being dated as even older than this, to about 300,000 years ago. It's a blurry picture, because it seems likely that there was quite a bit of inbreeding with neanderthals, on various occasions. This site in Morocco, Jebel Irhoud, seems to be even older, but dating and classification are maybe not as certain as the Omo site. The remains are classified as homo sapiens, but there looks to be some neanderthal element, in the tools and some features. https://en.wikipedia.org/wiki/Jebel_Irhoud

What did plants evolve from?

No, it has not. Plants split off early from the rest of life. Schematically, so:

Unfortunately this attempted explanation makes a common mistake. Matter is not converted to energy. What the equation says is that mass implies the presence of a type of energy, called rest energy. Both mass and energy are properties of physical systems. Neither is "stuff". You can't have a jug of energy, nor can you have a jug of mass. Any system comprised of matter that gains or loses energy will also gain or lose mass, according to the formula. So yes, your battery will gain or lose mass when charged and discharged. Note that both mass and energy are gained and lost together. They are not converted from one to the other. They go hand in hand. The formula is an incomplete, short, form of the full formula, which is E² = (mc²)² + p²c², where p is momentum (as measured from some frame of reference). So energy can be present due to momentum as well as due to rest mass. This accounts for the energy in radiation, which has no mass. If you have a nuclear reaction in which rest mass is lost, it just means some of the rest energy has been converted to energy in other forms, including energy in radiation and kinetic energy of particles. Just as when you discharge your battery, it too loses mass due to the release of electrical energy.

To begin with, you could, as now, have the first space stations orbiting within the Earth's protective shield. Then later, as stations got bigger, you could have the plant-growing surfaces situated on the outside facing in, so that the moist soil would be absorbing the harmful stuff. Obviously, that would be way down the line, on huge self sustaining space stations. Anything bulky that needs storing, like the water supply, could also be positioned on the outer surface. Maybe a station could generate it's own magnetic shield, a mini version of the Earth.

I've been pondering this for quite a while. I'm not enamoured of the 'inverse' approach, but I don't think it's impossible. But the way I see it, you would need more 'points' to interpolate. Levels of self-organization appear at different scales --already I know @studiot doesn't find this plausible--. Let's say: cells, multi-cellular organisms, planetary biota, and so on. At stellar level you would reach the point where no longer is there self-organisation. Instead, what you get is qualitatively different systems that, not only don't give rise to self-organisation, but actually erase information from their environment, and give it back to the universe completely thermalised (collapsing stars). I'm not saying it's plausible, I'm just saying the next Boltzmann of this world may be able to outline something like that. Very interesting. Let me keep thinking about this. One difficult aspect about the principle of least action is that, while its application is quite useful and simplifying in many cases, its meaning is obscure at best. It's a very abstract principle of physics.