The facts
A 2008 study popularized by Michael Blastland in his book, ‘The Hidden Half’, shows that genetically identical crayfish (clones) from the same batch and grown in a tightly controlled identical environment vary wildly in size, lifespan, behavior, appearance, growth rate, molting, reproduction, etc.
The microenvironment
In this case, the microenvironment is that which is supposed to explain the differential development of genetically identical organisms from the same cohort and in the same environment. This microenvironment thus includes disparate factors such as the proximity to the aquarium glass, to the light and – why not? – to the moon, the birth order, feeding order, randomness, etc. None of these has been proven determinant. Furthermore, the eye opener is the sensitivity to ‘whatever’ and the developmental range, not the ‘whatever’ itself. Especially since the purpose of homeostasis is to make the organism insensitive to the environment let alone the ‘whatever microenvironment’.
The meaning
If “fitness” were a valid concept, these clones grown in identical environments would have identical “fitness” and “natural selection” would not be able to distinguish. But the phenotypes vary considerably, so there is plenty for “natural selection” to select. But what exactly would be selected? Not the gene, but an unknown factor. Which makes “natural selection” an imaginary force. The story of the shotgun marriage… err modern synthesis… is thus invalid.
The extra
Couple that with the known long term coexistence of different alleles that are therefore not being selected “naturally”. And couple again with the homeostasis that affords organisms to pretty much ignore “the niche” and the environment to a large extent.
What else
We have known from twin studies that they are far from identical in appearance and behavior despite same genes and environment. We have also known that the genome contains insufficient data (not information!!! which is what one makes of the data) to specify the development or the structure or the behavior of any organism. Let alone all three. Therefore, we [should] have known that there’s something else besides genome and environment. Marmorkrebs only confirm what we knew: the “fitness-natural-selection-evolution” story is false.
The conclusion
“Fitness” is irrelevant, “natural selection” is an imaginary force, “evolution” has no valid mechanism therefore is false one more way.
Links:
https://zslpublications.onlinelibrary.wiley.com/doi/full/10.1111/j.1469-7998.2008.00473.x
https://www.amazon.com/Hidden-Half-World-Conceals-Secrets/dp/1786497778