@MikeElias since you're clearly up for discussing this, I think there are a few points about macro evolution which you should consider:

1. DNA is a hell of a lot like software code. A few tweaks to the "right" parameters can lead to pretty visible differences. Gigantism or miniaturization for example, show up in the human population every now and then -- it's just a tweak to when the body stops growing.

2. Most offspring die without reproducing. Look at how many seeds are created, or babies are born, vs what the replacement level would be. Surviving requires that you be both lucky and better than everyone else in your niche. Over long time periods, this massively parallel experiment hones a sharp edge.

3. Most mutations don't have visible effects. Life is, after literally billions of years of iteration, a massively complex thing with innumerable optimizations. Most of that complexity is micro in nature, not macro.

4. Macro changes (changing limb structure, feather structure, size, etc) aren't usually beneficial, if a species is already well optimized for its niche.

5. Things get more interesting when the environment is changing. A mere 20K years ago we were in an ice age. In the intervening time, a huge number of ecological niches have been created and destroyed.

6. Macro changes (visible changes to morphology, etc) are more likely to be beneficial during periods of ecological disruption. If a new niche has been created, and resources are just waiting to be exploited, then a relatively rare morphological change that enables you to access them is suddenly game-changing for you. You're no longer competing with your highly-optimized peers, you're competing with nobody. Even if the mutation carries significant downsides, it can be beneficial if it lets you slip into an unoccupied niche.

7. Once in a new niche, major downsides can be optimized away in subsequent generations. A really inefficient, barely functional feature can be honed and improved, so long as your new species manages to keep reproducing.

8. The over-production of offspring means even a newly-exploited niche will soon be full. Natural selection will soon be back to aggressively culling, and thus directing small variations towards something highly functional and competitive.

The idea that larger scale changes can happen quickly doesn't get a lot of discussion. It's not common, it's not how most evolution takes place. Slipping into an entirely new niche is rare, doing so through a novel morphology is even rarer. There are already a huge variation in morphologies (think of finches, jays, eagles, vultures, or hummingbirds, just to name a few bird groups), and so the odds of a new one arising and being better than all other morphologies for its local niche is rare. Moreover, while big changes in appearance are possible (again, it's code, little tweaks can make big changes), it's also quite possible to get from one morphology to another through tiny changes.

Since it can happen via small steps, and we have abundant evidence of small-step evolution happening, that's the most defensible explanation.

going back up

It seems highly unlikely that evolution is true, and highly likely Elon Musk will figure this out very soon. Here are some reasons:

A) Do complexity-increasing mutations even happen at all?

Evidence for the main mechanism of Darwinian evolution — an increase in genome complexity due to mutations — seems scarce.

I'm not a biology expert, but Richard Dawkins is, and here’s a video of him failing to think of a single example of a complexity-increasing mutation: https://youtu.be/YC10dUj1JmI

B) Complexity-increasing mutations must meet contradictory criteria

Yet for Darwinian evolution to take place, complexity-increasing mutations must not only occur — they must also meet all of these criteria:

1. Be extremely advantageous. The mutation must be so advantageous to survival or reproduction that the offspring of a single mutant specimen eventually come to dominate the gene pool of its entire species. Think of what it would take for this to happen to the human gene pool. Genghis Khan gave it a shot, and he got to about 1%.

2. Thousands of times. Evolution is gradual. Therefore, the extremely advantageous example of the complexity-increasing mutation must happen thousands of times, so that drastic changes (like those required for dinosaurs to evolve into birds, for example) can accumulate incrementally, one small change at a time.

3. Through useless intermediate stages. Since evolution is gradual, each evolutionary change involves many “intermediate” stages (such as between dinosaur and bird). However, there is nothing genepool-shatteringly advantageous about a dinosaur having twelve downy feathers sprouting out of its armpit.
   

To recap:

• It seems deeply questionable whether the main mechanism of Darwinistic evolution —complexity-increasing mutations — even happens, at all.

• Evolution requires it to happen to an extremely advantageous extent.

• Many times.

• Yet mostly in ways that are pointless, directly contradicting #2.
  

It seems to me like Darwinian evolution can’t occur without fulfilling contradictory conditions, millions of times, exclusively through a process that is rarely, if ever, observed (genetic mutations adding complexity).

C) Example of contradictory criteria

Birds for example are extremely complex, and genetic mutation can’t even come close to explaining how a lizard-type thing with an upright hip and solid bones simultaneously had mutations that gave it feathers, a backward facing hip, and hollow bones. As everybody knows, genetic mutations don’t just poof complex structures into existence like that. But a more gradual version isn’t any more reasonable, because there would have to be multimillion-year periods where dinosaurs have like 5 feathers, semi-hollow bones, and can’t fly — yet still somehow outcompete the rest of their species.

D) Credible skepticism is growing, even becoming an "intellectual trend"

Credible skepticism of evolution has already begun to emerge on Twitter and YouTube, steadily climbing the ranks of social status through voices that include, to varying degrees, Tucker Carlson and Eric Weinstein.

Tucker Carlson: https://www.youtube.com/watch?v=bv7hv0Xoa0Y

Eric Weinstein: https://www.youtube.com/watch?v=evBmuCNFnxw&t=140s

E) Elon Musk seems politically aligned with the intellectual culture of Evolution skepticism

Carlson and Weinstein seem to be in the same right-leaning intellectual camps that Elon Musk has also been in lately. Given that Elon has famously said things like “The most entertaining outcome is the most likely,” and it would be extremely entertaining if “the Bible-thumpers have been right all along” (and he gets to point that out), I think there’s a significant likelihood that Elon Musk will reject Evolution in the coming year.

NOTE: I would love to bet Real Money on this, if the right mechanism emerges. Not a ton, maybe $1000, but I'd love to see how a market like this would do among the general public.

@MikeElias What's your alternative mechanism to explain modern ecology?

@MikeElias How do you define genome complexity? Does the duplication and subsequent mutation of a gene count as an increase? If so, here are some examples.

@mongo I don't see why one is needed in order to falsify an existing theory.

@derikk @derikk Thanks! Very interesting. I’ve expanded my initial comment to provide more detailed arguments.

Regarding the Wikipedia page you linked me to — I'm seeing the section on "Model Limitations" and it says:

Limitations exist in neofunctionalization as a model for functional divergence primarily because:

1. the amount of nucleotide changes giving rise to a new function must be very minimal; making the probability for pseudogenization much higher than neofunctionalization after a gene duplication event.[6]

2. After a gene duplication event both copies may be subjected to selective pressure equivalent to that constraining the ancestral gene; meaning that neither copy is available for neofunctionalization.[6]

3. In many cases positive Darwinian selection presents a more parsimonious explanation for the divergence of multigene families.[6]

It sounds like they're pointing out 1) changes must be minimal rather than drastic; 2) there's no guarantee the mutation will be advantageous, and it may immediately die out; therefore, 3) "positive Darwinian selection" (i.e., new, advantageous genetic variations come to dominate a population) tends to be a better explanation.

1 & 2 sound like my own objections, which I have now added to “Part B” of my initial comment. Basically, these seem to be not just limitations but catastrophic flaws, and their supposed solution (“positive Darwinian selection”) is also catastrophically flawed, and not something that we can simply assume occurs. 😊🙏