But I would say as a mathematical process, pretty likely once you have the basic ingredients. Richard Dawkins has written some good popular science books like 'Climbing Mount Improbable' that talks about evolution in this light. His 'Selfish Gene' is also an excellent read. It is slightly more technical but definitely understandable without an immense technical background.
- cambrian explosion of life is seen as unlikely given that changing random genes or dna mutations has such a low success rate in generating new life, that an explosion of life happening all at once seems out of step with the math.
- we don't know how to create life at all. adding up bits and pieces of molecules into cells and onwards can be screwed up at any point in the process and has to start over from square one to succeed. people in the lab can't even get it right and they can write down their progress and adapt unlike nature.
- self-organizing molecules and natural forces guided towards life haven't been seen yet to exist in nature, it has no expressed intent or will to self-organize into life. randomness and infinite time just isn't enough
I don't see the evidence that local minima and maxima changes in body shape, size, ect, act to completely change the species of an animal.
There's a long debate running from the 1980s on this stuff, it's just getting views on youtube more recently and becoming properly structured and scientific arguments instead of just conjecture. The stephen meyer 'intelligent design', david berlinski 'doubting darwin', ect arguments. The hoover institute did a piece a few years ago on youtube.
James Tour has a great series on origin of life that shows in the hard tasks of applying biology we are way off knowing how any of this works. https://youtu.be/zU7Lww-sBPg
The counter arguments to stephen meyer's idea a 'heirarchy of information guides dna changes' seem to be good conjectures and nobody really has the next step in the narrative tied down yet. Some say the cell is the powerhouse of life and sidestep the necessity of explaining dna changes. Some stick to the evolved life like Lee Cronin on the Unbelievable podcast.
Just curious if anyone has a stab in the dark for the next step in the narrative. A heirarchy seems like a red herring to me, cause it just leads back to an energy based universe that produces information, but I'm not qualified enough to have a say.
I'm not very well versed on that topic, but as for speciation, that happens very easily. For example even relatively short term separation of populations can stop interbreedability, e.g. by changing mating behavior. Once that happens it's just a matter of a few million years of random walks to grow feathers where there has once been fur.
The complexity argument has problems because in the small error bars of dna replication, it's so easy to introduce a sequence that actively hurts the animal, or is useless. Producing a whole new limb or whatever is way more complicated that we'd like it to be.
The discussion overall is part of a larger move by the intellectual/theological groups to bring back language (and psychology elsewhere) back into the old energy and matter world-view.
I agree it's hard to answer, the James Tour video is a nice place to start because he talks about biological engineering problems that his students are covering for him. They make little nano-robots and the like in part of the presentation. It seems inevitable that we won't see an overall answer for thousands of years.
It isn't that much more complicated, though. Because as it turns out, you don't always have to code for that limb from scratch. You just have to flip a switch.
The key phrase here is "evolutionary developmental biology". We've learned that complex life has a lot of Lego-life quality - a lot of DNA codes for signals that enable or disable creation of whole organs at various locations, stages and cadences.
A TL;DR in four minutes by A Capella Science: https://www.youtube.com/watch?v=ydqReeTV_vk.
A nice example that video gives is that snakes have DNA coding for legs, it's just turned off. It can be turned on, and a snake will grow legs.
James tour's video in my parent post is far more in depth. Good luck.