I'm watching one of my favorite documentaries, Life Beyond by Melodysheep(if you haven't seen it then I urge you to check it out) and I'm just at the beginning where it's postulating how basic biology began on the newly-developed earth.
It brings to mind that the building blocks of life were nothing more than basic chemistry and energy in the form of solar radiation and geothermal from within the earth. To describe this process as "chaotic" would be an understatement but all of this eventually formed RNA and DNA which then became complex Life.
So this process, being nothing more than an accident at best, suggests, to me, that life is not only commonplace in the universe but may be inevitable in one form or another. However, did it all form the same way?
Way, way back when life first began forming I wonder perhaps if different kinds of life, ones that would seem "alien" by our standards, with "alien" here meaning if we put the two RNAs and DNAs next to eachother they would seem similar in form but couldn't be further apart, all formed on earth at relativley the same time and then vyed for dominance of the planet before our current knowledge of biological life became the dominant form. Earth itself was a violent and chaotic place full of different conditions that we would not survive in yet life found a way anyway. Life will have began in the oceans around places of intense heat and pressure but these conditions would have varried quite a lot as well. Which also suggests to me that life will have formed in multiple different ways rather than one single constant, such is evolution.
Of course, we'll never know if RNA and DNA structures are universal constants until we find life out there in the universe and even then we really can't be sure if it is or isn't a universal constant until we find one that's different, but Life will form om other planets, may be recognizeable by our standards, but could be completely and totally different based.
I don't know. Food for thought maybe. A question perhaps we will answer in the future when we discover developing life, uncomplex life, and complex life.
The future's very exciting in terms of finding out how exactly We happened and how and perhaps when We will happen again.
It is certainly possible other forms of self replicating molecules appeared on Earth in the Archean eon. It is even speculated some may have even survived to present day - look up "Shadow Biosphere" for a deeper dive on this.
It's really puzzling that with so much possibility, even alternatives to DNA/RNA, we still have aliens visiting us who have the same two legs, three arms and an antenna as ourselves, looking just like humans.
Also I'd be thrilled to see the Earth slightly more recently, when these fellas were still around:
https://bigthinkmedia.substack.com/p/tolkiens-middle-earth-wasnt-a-place
👀✨
I think life looks less like a lucky accident layered onto chaos, and more like a natural consequence of structured difference reaching a density where relevance can preserve itself. Different forms are possible, sure, but the emergence of life itself feels less contingent and more inevitable once those conditions exist.
Link to the full documentary:
https://youtu.be/dww8Hekngmg?si=GS7B5_OSWTIHj64v
There's also a part 4 coming out soon-ish.