Diderot said:
However smart goats may be, the novel phenotype induced by a correlated shift in morphology, as exhibited in Slijper’s goat, seems to be well out of grasp of the powers of the goat’s brain. A totally different explanation is in need here.
I think it’s safe to assume that Mary Jane West-Eberhard (and Slijper) had good reasons to discard the possibility of ‘trained muscles’ when she wrote: “(…) the leg muscles, including a greatly thickened and elongated gluteal tongue and an innovative arrangement of small tendons (…)”.
Don’t you consider the references presented in West-Eberhard’s treatise to be 'evidence'?
http://www.stri.si.edu/sites/publications/PDFs/West_Eberhard_2005_PNAS_STRI.pdf
Page 6545, Second column.
“Then, when it died an accidental death, Slijper dissected it and documented remarkable changes in muscle and bone, including striking changes in the bones of the hind legs; the leg muscles, including a greatly thickened and elongated gluteal tongue and an innovative arrangement of small tendons, a modified shape of the thoracic skeleton, and extensive
modifications of the pelvis (ref. 5, p. 53).
”
It doesn’t sound like anything is controlling it but the goat. It still sounds like intelligence, muscle training, and courage coming from the goat. Even the changes in the pelvic bones are part of its muscle training. Exercise changes the texture and even the shape of bone, especially when young. The direction of these changes is determined by the “free will” of the goat as an organized system.
Diderot said:
Have you not been able to find the kangaroo comparison? Allow me to assist you. West-Eberhard: “(..) Slijper, who noted that some of the novel morphological features of the two-legged goat resembled those of kangaroos and of other bipedal species such as orangutans “(p.6545)
Well, I guess that’s a decisive difference with the topic at hand.
http://www.stri.si.edu/sites/publications/PDFs/West_Eberhard_2005_PNAS_STRI.pdf
Page 6545, Second column.
"Similar effects on behavior and morphology are quite common in quadripedal mammals, including primates, forced or trained to walk upright (ref. 5, p. 42, figure 3.12 on bipedal baboon; ref. 25; see also descriptions of a bipedal macaque in ref. 62 and a bipedal dog in ref. 63)."
Maybe it was the same dog?
I am going to use “free will” as an analog to plasticity. “Free will” is a concept used in moral and legal discussions. It is ambiguously defined. However, “free will” is sometimes used as a synonym for plasticity. In your post, “direction” seems to be a synonym for “coercion”. So let me say that the goat isn’t being “coerced” to walk on two legs. The organized system called Slijper’s goat is made a decision.
“Free well” describes the sequence of expression for some of the genes. The sequence of behavior, including thoughts, is determined by the sequence of certain genetic switches in the brain. The sequence that goes off varies considerably with the environment that the brain features. There is even some “randomness” caused by the motion of the individual molecules, which you mentioned before. Therefore, there is no way to predict with certainty how different goats will deal with the situation at birth. The sequence of switching aren’t controlled by “free choice”, they are the “free choice”. The expansion of muscles due to exercise is also caused by switches that go off in the brain. Transcription proteins, including neurohumors and hormones, switch genes “on” and “off”. However, these switches are triggered by certain behaviors determined by the brain, which also works by “switching”. I would rather not say that the switching controls the choice. I think it is more accurate to say that the sequence of switching is the choice.
The article is really interesting but not for the reasons that you are stating. What the article suggests is the "choices" made by the organism can produce changes comparable in size to some of the changes brought on by natural selection. Every genome carries a "wardrobe" of adaptations that it may or may not express in a certain environment. The "random" choice of what adaptation to "wear" may greatly influence natural selection itself.
Here is where your article gets interesting.
On page 6546m first column,
“Recurrent phenotypes, similar or identical phenotypic traits with discontinuous phylogenetic distributions, are quite common in a wide diversity of taxa (5). Their similarity is sometimes attributed to parallel evolution, the independent origin of phenotypic similarity due to selection and adaptative change in similar environmental conditions.”
Scientists have been assuming certain variations are the result of variations in genetic sequence. There are many species that are said to have converged in some feature by natural selection. The author is suggesting that this is sometimes a mistake. Even the shape of a bone can be greatly modified by exercise, diet, and so forth. S
He also suggests that natural selection of genetic traits can sometimes be influenced by this “free choice”. This sounds like a generalization of the “Baldwin effect.”
To summarize: the only one directing the development of the hind legs is the goat. The sequence of genes controlling the hind legs provided the choices, but the epigenetic switch network made the final choice.
You didn't give enough credit to the goat. The goat, as a network of epigenetic switches, chose its path. In my value system, it chose well.