Before anyone comes for me, I grew up southern baptist – went to a private christian school & was homeschooled for a few years. The extent of my “science” education when it came to evolution & the origin of the universe was “if we came from monkeys why do monkeys still exist?” and “look at this galaxy that’s shaped like a cross, isn’t god amazing!!” I’m an atheist now and would like to have some sort of understanding of how our world came to be, but trying to figure it out as an adult with no real foundation has been incredibly difficult, and none of it’s making sense. I also know I’m asking a lot as all 3 of those subjects are pretty extensive, so if you know any good videos or books I’d love some recommendations!
In: Biology
For the big bang, and abiogenesis, we have absolutely no idea how or why these happened.
We can extrapolate the big bang happened by taking the current state of the universe and running the clock backward. Everything is expanding, so if you hit rewind the expansion undoes itself and you end up with a singularity. Where the singularity came from, or why it, seemingly, randomly started rapidly expanded, we have no idea.
We can extrapolate abiogenesis happened because we exist. Life came from somewhere, so it stands to reason it started in some way. The term we use to describe it starting is abiogenesis. We have *ideas* as to how it happened, but we don’t know the specific conditions that led to it.
For evolution, we can watch it happen. Genetics tend to be fairly fluid and change, sometimes rapidly. We have done experiments with bacteria and can watch evolutionary changes happen very rapidly in controlled environments. Evolution also isn’t structured. Organisms that survive pass on their genes. The genes that continue to be passed on become more pronounced over time. The ones that don’t get passed on simply dissappear. Natural selection gets twisted to make it seem as though some kind of selection processes is actually happening, but it’s not really. You either survive and pass on what you have or don’t. If you do, you’ve pushed evolution further. If you don’t, then whatever you have ends with you.
Just like the concept of God, there was a mass of energy that contained all there is, was, and will be that burst forth, kinda like a breath into nothingness. Science dictates that the inertia would eventually slow, or at least hold constant in zero gravity, but instead the expansion of the universe is speeding up. Meaning there’s a scientifically inexplicable force behind it. (A force that happened to place a specific star for Zoroastrian magicians to follow and establish what eventually became ground zero for our concept of time.) Science estimates 2 billion years ago, but let’s just go with the last 400k when humanoids evolved. I agree, I don’t think it was just apes evolving, there’s a missing link. Again, inexplicable to science.
Anyway, I think of God as The Big That Banged. That’s what ancient people tried to create a construct of, many times before we got to approximately 4000 BC when the beginnings of the Abrahamic faiths began forming from established Zorastrian beliefs. They went with YHWH as the conglomerate of the Canaanite gods.
A lot of good answers here. I have a similar background as you but I have no desire to claim atheism. I however don’t believe everything that is commonly taught by religious culture, especially about things that pertain to natural laws.
My understanding is that religious laws are separate of natural laws, and the two do not have to prove one another.
The natural laws we have speak for themselves, the observation that have been made show our current understanding. We may never have a full understanding of all natural phenomena because some natural phenomena may never be observable.
The religious laws are proved by what is purposely revealed (revelation). We will never have full understanding unless all is revealed.
This is a my understanding anyway.
When you get a chance, take a basic biology class at a community college (or just on youtube, they’re free), it will help
How the world came to be, we don’t fully understand. The “big bang” is our best guess so far, that’s more about physics and you can definitely take those clases on youtube or at a community college.
The secret to understanding evolution is to answer the question “why is <X> the way it is” with the answer “because every X that wasn’t that way got eaten before it could have babies.”
That’s a little simplistic, but it clears some of the confusing bracken out of the way so you can think about it.
Evolution is difficult to understand and easy to attack precisely because it takes SOOO LOONG under natural circumstances. However, an easier way to examine it is with fruit flies (that’s how we do experiments) and in a more easily accessible venue, dogs, because we have been deliberately evolving dogs and we went from 1 wolf species to THOUSANDS of dog breeds. They’re not separate species yet (all dogs can breed with all others) but they’re certainly pretty far along towards it.
The thing that’s hard about abiogenesis is also time – the process of genesis probably took .8 billion (800 million) years. THAT IS A LONG TIME. And that amount of time is difficult for us to picture, and the number of chemical changes taking place to create biology is also enormous but in that amount of time they’re relatively reasonable to expect they would happen.
I try to picture it with a carton of eggs and one pool ball – i can easily understand that if you randmly drop the pool ball and it’s forced into the carton, after 100 drops it’s pretty likely it’s going to have landed in each egg cup at least once, and it would take a couple hours. Now imagine billions of pool balls and trillions of cups. Over hundreds of millions of years you might be able to see how the pool ball egg cup thing scales up.
You have a journey ahead of you, it’s much more fascinating than made up religious stories, i wish you luck.
the basic thing to understand here are the time scales, e.g. we talk about WW2 as a very long time ago, the roman empire is ancient history, etc. but it is nothing compared to 2 million years, let alone 2 billion years ago
evolution works slowly, it appears it’s standing in a single lifetime, but as soon as you start increasing the time scales it’s obvious… e.g. 100K years ago dogs did not exist, only wolves, and all the dog breeds you see today are products of human selection
We need to dispel one myth right now.
Evolution, Big Bang, and Abiogenesis are 3 separate things. The way the question is written suggests you think of them as all the same thing. Despite what Christians say, they are not. They are separate and have to be discussed separately.
Evolution:
This is the one of the 3 that we know the most about. It’s the phenomenon whereby populations of organisms adapt to their environments over time. Crucially, the environments change too. And sometimes, populations get separated from one another, and get stuck in different environments, where the environments they have to adapt to are not the same.
The way it generally goes is like this:
– when an organism reproduces, the offspring will usually have the genetic material of the parent or parents
– however, some gets changed by mutation (random copying errors)
– normally this does very little, or is harmful. But on occasion, it can be helpful.
– the individual with the helpful mutation has more offspring than others of the species, causing the helpful mutation to become more common over time.
Of course, there’s a lot more that does and can happen. You could spend your whole career just learning about evolution, and youtuber [Forrest Valkai](https://youtu.be/1GMBXc4ocss?si=XAGjJITDKCYcLnOB) has. I recommend his content for this, he knows more than me about this and explains better than I do.
Abiogenesis:
Less well understood, but this is the event that would have been the beginning of life on earth.
As far as we can tell, RNA can and often does form spontaneously (ie just from random interactions of simple chemicals). All you’d need is a sequence to form that catalyzes its own replication, and you can get simple RNA-based life (well, “life”).
What I’ve just described is the RNA World Hypothesis. It’s not the only idea in town, and probably isn’t the whole story. But here’s [a video on the topic](https://youtu.be/K1xnYFCZ9Yg?si=PD3t8YB5qaxaGQiZ)
There’s some missing bits. Cell membranes would likely have come about independently; though they actually have the same chemistry as soap bubbles and aren’t hard to form spontaneously.
Big Bang:
This one, funny enough, was named by a detractor.
What we have here, is that the universe is expanding. This much is clear from measuring the light from other galaxies. The universe is getting colder and sparser.
So when we run the clock backwards, we get the universe in a hotter and denser state. If we run it far back enough, we get infinite density, about 14 billion years ago.
At least, that’s the prediction we get from relativity. That point of infinite energy density followed by density that’s finite and shrinking is what we call the Big Bang.
We know it accurately describes the universe pretty far back. It correctly predicted that at a few hundred thousand years old, the particles that were beginning to exist would emit light that would subsequently be ubiquitous. We’ve found that and subsequently called that the Cosmic Microwave Background.
But there are some known unknowns. We don’t actually know if the universe behaves the way we think it does when the energy density gets that high. We also have no idea what (if anything) caused it to occur, or if that question is even a meaningful one. We don’t know if we can unify gravity with the other 3 forces (electromagnetic, weak, strong) like we did with the first 3, and that would change what the early universe was.
The Big Bang model is pretty good for slightly later times, we just don’t know how well it does for really early times, or even t=0.
Evolution, the Big Bang, and Abiogenesis are three completely different things.
The Big Bang is an idea built on our observations of the position and relative velocity of stars and galaxies that are very far away, from which we can figure out that around 13.7 billion years ago, quite literally everything in existence was compacted into a very small region of space and time. Extrapolating further back gets difficult as we have good reason to believe that physics functioned differently, and we don’t really know what happened in the first few moments where everything was **reaaaaaaally** hyper-compacted. The Big Bang is sort of discussed in two parts; the first part is the idea that everything was further compacted into a singularity that birthed the universe (which is the theory), and the second part is just the observation that everything was very very very compact in the immediate aftermath of some event (which is more or less an observed fact).
Abiogenesis is just that life originated on it’s own from a mix of chemical and electrical reactions, powered by heat from volcanic activity deep in the early Earth’s oceans.
Evolution is an observation that species change over time, and the changes that increase likelihood of successful reproduction tend to be selected by natural mechanisms.
Given how each topic could fill in a timeslot or three, I’ll just focus on evolution.
All life^1 is centered around the DNA which acts as a “blueprint” for the organism, and it contains all of the information required for the organism to function. DNA is why identical twins look physically the same because the “nature” side of “nature vs. nurture” is identical.
Bits of DNA can be grouped into units called genes. The layman definition for that is that it’s a part of your DNA that “does one thing,” so a gene might define how hail follicles grow, or how much growth hormone is produced during adolescence, and so forth^(2).
The process of passing these genes on to your offspring is not perfect, so sometimes the genes are damaged. Maybe they’re copied incorrectly, or maybe the father spent too much time in a poorly ventilated basement which led to a stray ray of radiation from radon gas to damage the DNA. Mutations happen entirely at random because of this, and most of them are irrelevant. Not all of your DNA is useful, so damaging a part of it might not change anything at all. Sometimes, something very important breaks, so the clump of cells never even develops into something the mother notices because it’s that unviable. But sometimes a gene mutates in such a way that it can be useful. It’s very rare (after all, it’s much easier to break something than to repair it) but in that case, the mutation provides an advantage. If a trait is harmful or beneficial, that causes **evolutionary pressure**. If the trait is bad, then the offspring is statistically more likely to die out, so the genes spread less. Conversely, if the trait is positive, then the genes are more likely to spread throughout the population.
Dogs are a good example of this. In the wild, a friendly wolf with a muted survival instinct would die off pretty quickly and take those traits with it, but if that happens to, say, an abandoned wolf cub which is picked up by a tribe of humans, it can become an enormously favored trait because humans love to pack bond. Humans can artificially^(3) select for these traits, so over thousands and thousands of years, when humans always bond most with the friendliest and most cooperative wolves, eventually you have something that is so different from a wolf that we call it a dog. A part of it is unintentional (a man might just dislike and reject a dog that is aggressive and bites him, leaving it to find its own food) but we can also selectively breed for specific traits which is how we’ve specialized wolves into everything from lap-dogs to shepherds, service dogs or [turnspit-turners](https://en.wikipedia.org/wiki/Turnspit_dog).
This is how **microevolution** works, i.e. how different traits appear and spread within a species. A dog is born with an abnormally expressive face, and because that makes it easier for humans to communicate with it, it becomes a beloved dog and the trait gets passed on as much as possible.^(4) Because of how strongly humans can influence which genes are passed on and which aren’t (which removes a lot of the randomness from the kind of evolution that happens in nature: even the fastest, smartest, most genius wolf might lose to its mangy brother in a competition on a bad day) the variety of dogs you see is staggering.
**The imporant part here is that it is all, ultimately, just statistics**, and evolution has no overarching goal to it. Humans can use it for their own purposes as mentioned above, but evolution itself is a blind and deaf force. If a canine is born with a mutation that makes its brain smaller and less responsive to danger, it will likely die in the wild, so the trait is unlikely to spread. If that mutation happens to a dog, then it might not matter one whit because humans will keep it alive anyway. Even though to the person reading this, a “smart” dog might seem better than a “dumb” one, evolution neither cares nor prefers: if it works, it works. If it doesn’t, then it doesn’t, and that’s why modern dogs (literally) have smaller brains than wolves and why many overbred dog breeds have debilitating health issues. Subjectively, it is terrible that a dog has such a malformed skull that it can’t breathe properly, but objectively, if breeders see that trait as “pure” and make the dog have a lot of offspring, the trait will live on.
**Macroevolution** (speciation, in this context) is just microevolution over and over again. This is where many religious sects draw the line (largely because microevolution is so blatantly obvious that it’s embarrassing to attempt to refute it) but there is no real reason why small changes over enormous timescales wouldn’t yield a result that was entirely different from what you started with. The rule of thumb^(5) for defining species is if they can produce fertile offspring together, so if you pile a change after change after change in different directions for two separate populations of a species, eventually they will no longer be compatible.
Modern humans showed up about 300 000 years ago, but saying that we came from monkeys is glossing over some details. Chimps and humans share a common ancestor, but that was some ten million years ago, which was effectively just a primitive and weird-looking monkey. Two groups of these creatures got separated at some point just by chance, and because of different environmental pressures, one group drifted towards what would become modern chimps and the other towards what would become modern humans. The “why are there still monkeys around” argument is fundamentally misunderstanding the process, so it’s like asking “If Estonia seceded from the USSR, why are there still Ukrainians around?” which is silly because one of those nations is long gone and the only thing in common between the remaining two is that both of them have a hot-topic border eastward.
It’s important to note that none of what I’ve written is in any way related to **abiogenesis** or how life was formed. The theory of evolution doesn’t concern itself with where life came from, whether it was from a meteor, a brackish puddle or the Gnostic demiurge going against the emanations to bring forth life. Where life came from is very much an open question, and a very difficult one to answer at that because on Earth it happened over four _billion_ years ago.
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^(1) How you define “life” is subjective, so I’m just focusing on anything that looks like bacteria or bigger.
^(2) How genes actually express themselves is horribly complicated even without getting into epigenetics. It’s rare for one gene to be solely responsible for any one trait, so whether you’re tall or smart or any other thing is usually the result of a complex web of related genes.
^(3) “Artificial” is a loaded term here, really. Any selective pressure is just as valid as another, so friendly pets getting all the care and attention from humans is no different from taller-necked giraffes eating better or faster gazelles outrunning predators.
^(4) Dogs have significantly more expressive facial muscles than wolves do. It’s even in the whites of their eyes: eye contact is important for humans, so dogs which can indicate which way they’re looking work better with humans.
^(5) Again, real life is complicated and doesn’t fall into neat buckets, so you always have edge cases which buck the trend, but unless you’re a specialized biologist, the rule of thumb is just fine.
Evolution and the origin of universe are two different things, but both have modern theories which explain much of what we observe quite well. Monkeys are not ancient creatures left over from the evolution of people. They are modern, contemporary animals that themselves have evolved from earlier forms. The overwhelming evidence indicates that both humans and apes have a common ancestor and that the two lines diverged from each other a long time ago. We have a great deal in common with other animals, especially apes. More that 90% of our DNA is identical to that of modern apes, but 10% is a big difference. The evolution of the cosmos however, is different thing and I”ll leave it to others to explain it.
The most important thing to take away with evolution is understanding Deep Time. The city-state of Ur is considered the oldest human civilization, and it was founded around 4,000BC (6,000 years ago). This compared to the age of our planet, the age of our star, the age of our galaxy is hardly blink of the eye. The comparison often made is, if you lay the universe out on a calendar, so the Big Bang (14 billion years ago) happened at the first second of January 1st – all of written human history is the last second before midnight on December 31st.
That is all to say, there is an enormous amount of time that passed before we could even write, so much it’s hard for the brain to process (much like the enormity of space itself). Human history is told in thousands of years, evolution unfolds over millions of years. That’s why you won’t see chicken lay an egg one day, and the baby that hatches out is a newly evolved species. It doesn’t happen on time spans we live in. Nor is it so dramatic or instant. Its very tiny changes happening over incredibly long stretches of time.
To specifically answer the “if we evolved from monkeys, why do monkeys still exist?” claim. We didn’t. Both us, monkeys, and chimps evolved seperately from a common ancestor species. Humans evolved differently, because Africa was losing it’s jungles at the time. Our ancestors evolved better survive on the ground, instead of in the trees. Meanwhile monkey ancestors, living in areas that still had bountiful trees, had no reason to evolve better suited to the ground – and in fact evolved to be more suited to the trees.
As for the Big Bang, and Abiogensis; we haven’t come up with conclusive answers. We just have theories.
One idea for the Big Bang, assumes multiverse theory is correct. When two other universes collided, the Big Bang happened at the point of impact and birthed our universe.
The most recent idea I heard for Abiogenesis is it happened at deep ocean vents. There’s a lot of heat energy to be had at these vents, and they are also rich in organic matter spewing out from underground. The rock of these vents is very porous, like a sponge. Those tiny pores create a round scaffold on which proteins could build a cell wall. We feel the cell wall is one of the most critical steps for life to exist, as it separates the lifeform from the environment.
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