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Welcome to ANI In The Air Online and Around Baltimore.
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This is Wondrous Wednesday, where I talk about something wondrous.
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So last time I kind of did a brief overview of evolution, so I thought it'd be relevant
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to kind of sketch out the beginnings.
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So the real beginning is, of course, the Big Bang, which is when the universe basically
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started.
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I think that's about 13 billion years ago.
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That was just kind of a hot mess of energy in a very kind of small region, and then it
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rapidly expanded cooling, and in that cooling there were slight variations that allowed
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gravity to start clumping things together.
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And then that sort of led to the basic formations of galaxies and stars, and that first generation
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of stars, I believe it was just basically the very light elements, and then when they
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collapsed after many billions of years, that collapse gave enough energy to kind of create
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the heavier elements, which we use to have planets and life and all that.
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So basically the Sun was formed from, and our solar system was formed by a big cloud
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of gas that was remnants from other stars exploding, and that happened about 5 billion
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years ago, I believe, and then the Earth formed about 4.5 billion years ago, and then somewhere
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between maybe 200 million years after that to maybe a billion years was when life started.
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It's a little unclear exactly when life started.
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There was a lot of stuff happening in the solar system at that time, I believe lots
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of asteroids crashing into the Earth, potentially killing and wiping out whatever life had formed
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at those points.
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So it's kind of a mess, but I do believe 3.5 billion years ago they have confirmed evidence
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of life, just relatively early on.
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That life was pretty primitive by our measures, but one of the very fascinating things about
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the origins of life and that whole story is that it really pulls together so many different
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disciplines.
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There's the physics of the creation of the Sun and the planets, and of course all the
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kinetic energy coming in from asteroids and various other sources of energy that are crucial
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for getting things to happen, possibly some of the radiation from the elements in the
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Earth's crust, there's obviously the volcanic activity, there's sunlight, and then there's
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also lightning strikes, lots of lightning strikes.
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So physics has several inputs into this process.
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There's also of course chemistry, which is where everything's kind of mixing together,
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and then of course there's the trying to figure out in some kind of fossil record or other
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means of trying to actually find life, I think they might call that paleobiology.
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And then there's of course the actual some of the experiments to try to recreate life
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in the laboratory, or at least elements of it, as long ago as the 1950s, they demonstrated
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that the conditions of the Earth they thought at the time, way back when, could in fact
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create amino acids just from those elements.
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Amino acids are like, you know, the building blocks of our proteins and communication mechanisms
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in the cells, the DNA and the RNA and all that good stuff.
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So the more or less the basic theory of the origins of life is that there were various,
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there's enough energy and floating materials, ways of kind of interacting with things and
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enough time, a billion years is a really long time, to essentially create some kind of self-replicating
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system, it wasn't necessarily quite what we would call life, but it'd be, you know, pretty
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much getting there and, you know, it's crucial that it could happen, you know, by basically
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chance and it could be even a low probability of chance, you know, if it's something that
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comes about, I don't know, one out of a billion sort of interactions, it would be almost guaranteed
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to happen over a billion years and, you know, all those interactions, I mean, it's a huge
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planet, a lot of stuff happening, so, you know, even a couple hundred million years
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isn't too long for, you know, it all depends on the probabilities of these things happening.
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And you know, it's a little bit tricky, you need something that can kind of keep like
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replicating itself in some fashion through some cycle, you need it to be stable enough
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to, you know, accomplish that, needs to be able to survive the environment that it's
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in and actually thrive on it and, but you also need it to be able to not be so stable
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that it doesn't change, it's important that things can change in this process because
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it wasn't the end of the step. So, you need stuff that not only self-replicates but self-replicates
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in some sloppy fashion that allows it to basically start the evolution process. Doesn't need
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to change much, just a little. So, you know, they still don't quite know the pathway of
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how life started, there's sort of some crucial ingredients involved in cells, you know, the
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internals of a cell have a lot of proteins that are kind of the machinery of the cell,
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they actually can look like machines and they kind of fit together and it's always about
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kind of randomly hitting one another. You know, it's not exactly like, you know, some
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sort of top-down conscious control going on, it's just there's a certain number of proteins
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that interlock in a certain way and they're just kind of floating around in the cell very
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actively and hitting one another and, you know, things happen. Also needs energy, always
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needs energy to accomplish changing things and that's, you know, that's where like sugars
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and stuff are used, which, you know, is the backbone of carbon basically storing energy
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connections. So really, hydrogen and then, you know, surrounding the cell is the cell
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membranes, sort of a fatty structure that insulates it from it all. So somehow life
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had to go from just a bunch of molecules floating around and hitting each other randomly into
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something like a cell, which is, you know, quite fascinating to think about how everything
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fits together. It's, you know, it's kind of hard to visualize it and it's important to
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understand just how long a billion years is. So, you know, that's going from a few molecules
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sticking together and then like, you know, attaching more of itself to the surrounding
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thing then breaking apart and creating these things and all that and then from that somehow
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eventually getting it all kind of contained in a cell and then having, you know, the very
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complicated message structure of RNA and DNA. I mean, that's pretty wondrous to me that
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it all came together. Again, a lot of it is just a bunch of randomness, freely available
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energy. You know, again, sunlight, lightning strikes, radioactive elements and then time,
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just vast amounts of time. That's something that is, you know, pretty important in understanding
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the evolution of life. Time does a lot of stuff and it's not something unrelated to
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human development as well. You know, there's a lot of time giving in the kind of evolution
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of a person from when they were born to when throughout adulthood. That time just is constantly
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changing and, you know, initially there's a lot of change, massive amounts of change
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and then it kind of slows down, gets more refined, ever more refined. And it's really
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that sort of first steps that are quite remarkable and, you know, it's quite unlike the thing
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that comes later. So, it's true of evolution and true of, you know, human's life. You know,
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it's the early steps where things look really like, wow, it can take a while to accomplish
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much. You know, it takes, what, a human child about nine months to a year to figure out
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how to walk. A couple years maybe to start really being able to talk, you know, somewhat
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coherently and well and several more years beyond that to be, you know, really being
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able to have conversation and all that. So, you know, it's very much reflective of just
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how long it takes for life to have started as well. You know, I like that kind of symmetry
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of our self-replicating process of life evolving and every individual kind of doing a little
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bit of a homage to that process. All right, well, think I've rambled on long enough. Thanks
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for listening and I guess we will move on up through the evolutionary history next time.