Charles Darwins big idea was natural selection, the mechanism by which evolution happens. It was not a new idea that species had evolved over time from common ancestors (Larmarck is well known for example), but nobody had suggested a plausible mechanism for how it worked before Darwin and Wallace.

> Darwin didn't just say "evolution happens", he demonstrated it.

Not really. He described the idea in greater detail, but he didn't demonstrate it. It's actually quite similar to the pre-Socratics in that way.

Darwin performed hybridization experiments that demonstrated the principles, and the topic appeared as a section in Origin of Species. However, Darwin's experiments lacked statistical rigor -- he didn't do enough variations to make statistical assertions. This gap was later adeptly filled by Mendel. Freeman Dyson did a wonderful lecture on this topic right before his passing, which covered various forms of biological & cultural evolution spanning Darwin to present:

https://www.ias.edu/news/in-the-media/freeman-dyson-biologic...

If you want an alternate source:

https://www.nature.com/articles/s41437-019-0289-9

He formalized it as a theory that could then be tested, reviewed for internal consistency, used to model/explain the world, etc.

Yeah I wouldn't call what he did primarily demonstrating, but gets you on that path (and IIRC he had several examples to point to for concepts).

He did in his book. He gives instructions for how to perform his plant hybridization experiments in your own garden.

On the subject of demonstrations-in-the-lab, there's an interesting experiment that's been tracking and sampling some E.Coli since 1988.

https://en.wikipedia.org/wiki/E._coli_long-term_evolution_ex...

He did refer to experiments which demonstrates "natural" selection in action, like pidgeon breeding.

Can you provide examples where he demonstrated it? I mean that would be pretty epic him able to demonstrate it happening.

I'm reading On The Origin of the Species right now. He discusses human selection of domestic animals and plants at length as a fairly convincing analogy, then connects it to observations 'in nature'. It's hard to demonstrate something that is observed (vs something controllable), but the argument is quite comprehensive.

And yet their speculation gave us the conceptual apparatus to make sense of the data that lead to the discovery. Science never operates in a vacuum.

It's also interesting to note that Darwin's theory had to be reformulated several times before it could match contemporary data. I'm talking specifically the Modern Synthesis (Darwin + Mendel) but also more contemporary syntheses such as Koonin, Huneman & Walsh, etc. [1]

[1] https://en.wikipedia.org/wiki/Modern_synthesis_(20th_century...

> But that misses the whole point: no other scholar was able to embed a theory of evolution into the scientific body of knowledge.

Not even Alfred Russell Wallace?

The Mindscape podcast has a recent episode on this topic - Sean B. Carroll On randomness.

Aristotles Ladder of Life considers the progression of species. But without mechanism.

Mendel (widely referred to as the father of genetics) had already demonstrated it.

> Mendel [...] had already demonstrated it.

No. For 3 reasons:

1) Mendel's work "appeared" after Darwin's. The Origin of Species was published in 1859. Mendel presented his work on 1865. True, Mendel did send a letter to Darwin explaining his work but it seems very unlikely Darwin ever read or understood it. Mendel had a very obscure and hard to understand writing style.

2) By "appeared" above I refer to the fact that Mendel's work remained completely ignored for decades. All of his scientific papers were burned by the abbot that succeeded him in the monastery. It was Hugo DeVries that rediscovered his work at the beginning of 20th century. Again, Mendel's hard writing style played against him.

3) Mendel never cared about random mutation and natural selection, the fundamental elements of evolution. He only recorded the combinatorial patterns on pea's traits deducing the recessive/dominant traits. Truth be told, today these are a small part of gene expression. The metabolic pathways of gene expression are much more complex than just the recessive/dominant pattern.

Or how the bible is telling the story of Eve(Mitochondrial Eve) and Adam(Y-chromosomal Adam)

Mitochondrial Eve and Y-chromosomal Adam lived not in the same period of time.

Does it matter? I mean it’s still close enough for such a prediction so long back.

What I am saying is that, like with the “atoms”, the intuition was there. They just didn’t have the means to prove stuff

People predicted lots of things. You can’t look back and say “oh, they predicted X right” while conveniently ignoring all the other ways they predicted it wrong.

See also: Post hoc ergo propter hoc and Texas sharpshooter fallacies.

Why can't the same argument be hold for Pre-Socratic philosophers and the "atom"?