After you meet Apollo, Zefram Cochran, and evil versions of yourself, you probably start taking these things in stride.
Gold is not a necessary trace element for any biological system - it isn't used as the cofactor in any protein or enzyme as far as I'm aware. Tungsten, another 5d-orbital series, D-block element, is present in some bacterial enzymes but not in eukaryote-produced ones. I believe Tungsten is the biologically active element farthest up the periodic table at Z=74, gold is at Z=79.
Gold nanoparticles might potentially be able to damage DNA in mammalian cells.
Scientific Opinion on the re‐evaluation of gold (E 175) as a food additive - - 2016 - EFSA Journal - Wiley Online Library
Yeah, it's thought to be safe in its pure form as long as it's not reduced to particles of a few gold atoms in size. Ionic compounds of gold are known to have medical side effects, particularly to the kidneys. Platinum is also not kind to the kidneys and causes nerve damage as I know from personal experience.Contrary to other metals, gold is not toxic to the human body (at least not much) which is why it is used in prostheses.
What I mean is Kirk knows that it's not the real Lincoln so why not just saying so to his face? Isn't that what they normally do?
Are we? Do you have a link? Archaea, bacteria, and eukaryotes have substantial differences but the general opinion is that they had a common origin with eukaryotes being formed from an endosymbiosis of the other two, which likely had a common ancestor in a confined system, be it a vent, clay matrix, or gyserite. A big puzzle for eukaryotes is why no intermediate forms appear to have survived. My suspicion is that one or more mass extinctions nearly wiped them out, acting as a great filter.We're already fairly sure life has evolved on Earth more than once.
My money's on all three possibilities being true.
The asteroid that collided with the Earth that killed the Dino's is important because material composition of asteroid might have been responsible for causing the split in money DNA that became human DNA along with causing a mutation to happen that also caused the early human/monkey brain, the brain present right after humans split from monkeys, to begin to enlarge.
Most non-humam life on Earth has been tracked to very in the evolution of Earth, millions of years before humans. If humans had a footprint and had been present on the Earth at the same time as early life, there would have been tell tale,signs of human DNA.
Monkeys have been around for about 30 million years compared to humans being around for 300 thousand years, approx.
If the dino killing asteroid struck 65 million years ago, monkeys have been around for 30 million and humans for 300k years, then the asteroid does appear to have caused a shift in the DNA of the animal species that was the monkeys ancestors that existed during the time of the dinosaurs.
The asteroid could also have carried DNA, either naturally or even artificially, from another planet in the galaxy, to Earth.
We're already fairly sure life has evolved on Earth more than once.
Are we? Do you have a link? Archaea, bacteria, and eukaryotes have substantial differences but the general opinion is that they had a common origin with eukaryotes being formed from an endosymbiosis of the other two, which likely had a common ancestor in a confined system, be it a vent, clay matrix, or gyserite. A big puzzle for eukaryotes is why no intermediate forms appear to have survived. My suspicion is that one or more mass extinctions nearly wiped them out, acting as a great filter.
Did you read the article? Do you understand metaphor?Article about gold in bones.
https://www.spokesman.com/stories/2017/mar/14/museum-finds-gold-in-the-oldest-bones/
Yeah, those are hypotheses. We don't have any strong direct evidence. When you go back four billion years, all you have are ambiguous chemical traces and rock formations. I happen to believe it's possible that life got started more than once but it's also hard to define what constitutes life below a certain level of complexity. If we were to find an existing definitive, separately evolved biosphere on Earth or elsewhere, that would make the scenario a lot more probable.Okay - most of the articles I can find now are (of course) behind paywalls or are rather old:
https://www.newscientist.com/articl...sily-that-it-started-not-once-but-many-times/
https://www.newscientist.com/articl...ming-did-life-evolve-on-earth-more-than-once/
http://astrobiology.com/2017/01/did-life-start-more-than-once-on-earth.html
This one is debatable, can't find the original article but, don't have an account at the original source so..?
https://www.theguardian.com/science/2009/feb/15/microbes-earth-tree-of-life
Yeah, those are hypotheses. We don't have any strong direct evidence. When you go back four billion years, all you have are ambiguous chemical traces and rock formations. I happen to believe it's possible that life got started more than once but it's also hard to define what constitutes life below a certain level of complexity. If we were to find an existing definitive, separately evolved biosphere on Earth or elsewhere, that would make the scenario a lot more probable.
ETA:
Nick Lane and colleagues have a theory where the very distant, very simple ancestor of bacteria and archaea, aka the last universal common ancestor LUCA, probably arose once in the same physical location - his preference an alkaline sea vent - sharing the same RNA/ribosome protein-building mechanisms but developing different cell membranes, proton pumps, enzymes and DNA replicase when they left the vents. Probably, but it's just conceivable that they developed separately. The domain of eukaryotes, such as humans, is a result of the fusion by endosymbiosis of those two domains.
A Bioenergetic Basis for Membrane Divergence in Archaea and Bacteria (plos.org)
A Leaky Membrane and a Sodium Transporter at Life’s Great Divergence (plos.org)
One criticism is that molecular nanomotors such as ATP synthase, which is a molecular assembler driven by a turbopump powered by a proton gradient across a membrane, are staggeringly complex. Such molecules presumably had simpler forms from which they developed but we don't know what those were. A lot of the nanomachinery in cells does look almost engineered but our experience with computer simulation of evolution by natural selection tells us that it is astonishingly good at producing almost baffling complexity.
The following books by Nick Lane are worth reading on the subject of the origin of life on Earth.
The Vital Question: Energy, Evolution, and the Origins of Complex Life: Amazon.co.uk: Lane, Nick: 9780393352979: Books
Life Ascending: The Ten Great Inventions of Evolution: Amazon.co.uk: Nick Lane: 9781861978189: Books
I find his arguments compelling but at this vast distance of time, it's extremely difficult to be sure exactly what happened. We might never know for certain.
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