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The ancient Greek (of course!) Anaximander was the first to lay out a theory of evolution - over 2,000 years ago! He came this close to developing the theory of Natural Selection as the mechanism for evolution.

Here's the thing: people knew this. The idea of evolution was not new in Darwin's time. What was new was the idea that the mechanism of evolution could create new, and diverse species. Hence the name of Darwin's seminal work, On the Origin of Species.

Darwin did not in fact describe a mechanism for the origin of new species. He described how existing species could change over time. How speciation occurs required some new ideas.
Anaximander's idea of evolution was basically just speculative fiction.

He simply suggested that man and animals came from water with no evidence whatsoever, and that early man must've needed to survive in the mouths of fish to withstand the elements.

Darwin actually collected scientific data and observations from finches, fossils, and brachiopods to substantiate his claims. The key observation needed to make the theory work was an understanding that the Earth was millions of years old, which was only recently established (speculated by folks like his grandfather Erasmus Darwin and confirmed by his colleague Charles Lyell)

Really? Count me surprised if the ancients had a workable theory of evolution - there are pretty important details that you need to make the mathematics work, like the fact that inheritance comes in discrete units (which today we call genes). As far as the popular history goes that was only shown much later, when Mendel started counting his peas.
After an admittedly very cursory search, I get the impression that his 'theory' is a bit like Democritus' atomic 'theory': it has the concept, but very little of the content of our current understanding (not that this in any way diminishes either of them: to still be discussed today is about as close as you can get to academic immortality.)

I also find it interesting that Charles' paternal grandfather, Erasmus Darwin (a doctor, author, active member of the Birmingham Lunar Society and Fellow of the Royal Society) felt that life had evolved. Furthermore, one of his arguments was one also put forward by Charles: an analogy to the breeding of domesticated animals, as can be seen on page 548 of his opus Zoonomia, or the Laws of Organic Life.

https://early-evolution.oeb.harvard.edu/sites/hwpi.harvard.e...

Darwin didn’t know anything about genes, or how inheritance actually worked.
Not initially, and indeed that was one of the major early criticisms of his theory. But he learned of Mendel's work after publishing his own - The Gene has a nice history of this.

Edit: I think you're focusing on the gene part too much. What's important is that inheritance is discrete, regardless of what actually carries it, rather than continuous. Mendel proved that part.

Edit edit: scrap that part about Darwin I misremembered

I think you are focusing on gene too much too.

At the gene level it is discrete yes. It isn't at specimen scale, and appears more continuous.

It's very possible ancient Greeks didn't understand the discrete aspect, it doesn't mean they didn't know in some ways more than we know of evolution. I would assume they did given the numerous incredible polyglot thinkers we find traces of.

Traces, it would seem the biggest part of ancient times writings are gone. And why just thinking of the Greeks, so many civilisations have vanished, many which the left over of their produces confuse us. More civilization disappeared than the count of those we know had existed.

The food stocks, cattles and other pets that accompany us today were the result of non natural selections spanning many human generations. To think civilisations that were able to accomplish that didn't have, in a way, a more comprehensive understanding of natural selection is pretty condescending, or naive of our own understandings.

Sure they probably didn't come up with Crisp, they may not have been able to observed the structures of DNA, they may not have even known how bacteria looked like. Given the challenge I'm in admiration for their findings given how blind we assume those people were.

No, Darwin never learned about Mendel's work, even though Mendel sent him a copy (which was well after Darwin had published the Origin). The copy in Darwin's library has its pages uncut -- meaning that Darwin never got around to even opening it. Darwin instead believed in blending inheritance rather than discrete units.

As for Mukherjee, while his Emperor of All Maladies about cancer was brilliant, The Gene (and Mukherjee's New Yorker article that he expanded to make his book) has a lot of issues as many geneticists and molecular biologists such as Walter Gilbert and Tom Maniatis pointed out at the time.

Thanks for the correction, I must have remembered that wrong. In that case Darwin didn't have the full theory yet either I guess. But my point about the ancients stands.
I agree, we should celebrate the ancients for how much they discovered despite the obvious difficulties.

On your point about things being more continuous on a species scale - two things can be true. Natural selection acts on allele ls of each gene, which are discrete things. But it's also true that large numbers of genes acting in cooperation can produce a continuous spectrum of phenotypes.

> But he learned of Mendel's work

Did he? Where is that documented?

You're right, I misremembered that. Thanks for the correction.
I think a lot of folks miss the point that gene theory and evolution theory can exist independently of each other and that an understanding of genes is not a prerequisite for the understanding of evolution.

When Darwin's theory of evolution by natural selection came out, it was sensible from the perspective of animal breeding. It did not explain how new variation came about, but the fossil record alone in the mid 19th century was sufficient evidence for most educated people to undeniably understand that new variation did occur over time. For reference, the first complete Archaeopteryx fossil was discovered in 1861.

It is only today with hindsight, Mendel's gene theory, and molecular evidence from electron microscopy that the whole picture is pretty clear. Variation over (really long periods of time) comes from mutation, and natural selection is only one of four major mechanisms that alters gene frequencies in a population.

The four are mutation, natural selection, genetic drift, and migration.

Right, you can understand them independently, but of course in reality they are intimately linked.

For instance, isn't genetic drift just a consequence of mutation and natural selection? Neutral mutations with weak selection pressure will tend to build up in a population over time.

Genetic drift is not actually a consequence of mutation and natural selection. Hypothetically, if there was some sort of alien planet where the living inhabitants reproduced and used a replication system that doesn't undergo mutation and has no positive or negative natural selection, there would still be genetic drift and you would still observe changes in the allele frequencies of the population over time, and in small populations, genetic variation could slowly disappear...
Ah, if I understand you correctly, you're actually saying that genetic drift is not _only_ a consequence of mutation/selection, right? Because of course allele frequencies change in a population just from meiosis.

(I'm not sure your hypothetical is valid though - where would the variation in alleles have come from in the first place without mutation/selection?)

Since this is hypothetical... a wizard did it... You're right though. The initial allelic variation would have to come from mutation, a wizard doing genetic engineering, or some sort of weird alien mechanism that actively creates allelic variation.
The theory of evolution evolved