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Monday, July 22, 2019

Reactionary fringe meets mutation-biased adaptation.
5.2. The Modern Synthesis of 1959

This is the eighth in a series of guest posts by Arlin Stoltzfus on the role of mutation as a dispositional factor in evolution.


Reactionary fringe meets mutation-biased adaptation. 5.2. The Modern Synthesis of 1959
by Arlin Stoltfus

As we learned in What makes it new?, the newness of the effect of biases in the introduction process results from a classical assumption that evolution can be understood as a process of shifting the frequencies of existing alleles. How did this position emerge? Was it a technical, mathematical issue?

Friday, July 19, 2019

Reactionary fringe meets mutation-biased adaptation. 5.1. Thinking about theories

This is the seventh in a series of guest posts by Arlin Stoltzfus on the role of mutation as a dispositional factor in evolution.


Reactionary fringe meets mutation-biased adaptation. 5.1. Thinking about theories
by Arlin Stoltzfus

A wikipedia page disambiguating "Modern Synthesis" defines neo-Darwinism as
"the state-of-the-art in evolutionary biology, as seen at any chosen time in history from the 1890s to the present day."
Because "neo-Darwinism" and the "Synthesis" are conflated with whatever is widely accepted, they are now regularly attacked on grounds that are completely unrelated to genuine neo-Darwinism or the original Modern Synthesis, e.g., as when a network of life (rather than a tree) is invoked as a contradiction of Darwinism. The attack by Noble (2015) on the
"... conceptual framework of neo-Darwinism, including the concepts of "gene," "selfish," "code," "program," "blueprint," "book of life," "replicator" and ˜"vehicle."
is entirely a critique of late-20th-century reductionism à la Dawkins, and addresses neither neo-Darwinism (selection and variation as the potter and the clay), nor the original Modern Synthesis, which is simply not reductionistic, but positively invokes emergent phenomena (population-level forces, the gene pool as dynamic buffer) in the service of selection as a high-level governing principle.

"The state of the art" is a phrase that needs no modification. Nothing good can come from linking it to the name of a dead person.

Saturday, July 13, 2019

Reactionary fringe meets mutation-biased adaptation.
5. Beyond the "Synthesis" debate

This is the sixth in a series of guest posts by Arlin Stoltzfus on the role of mutation as a dispositional factor in evolution.



Reactionary fringe meets mutation-biased adaptation. 5. Beyond the "Synthesis" debate
by Arlin Stoltzfus

The authors of TREE's hatchet piece imply that the theory of Yampolsky and Stoltzfus (2001) is somehow not new, citing ancient work from Dobzhansky and Haldane. In Box 1, they argue that this theory is part of "standard evolutionary theory," showing a 4-step derivation ending in Eqn IV, which is Eqn 2 of Yampolsky and Stoltzfus (2001), and informing the reader that this is based on "classical" results from Fisher, Haldane and Kimura, who are named, while Yampolsky and Stoltzfus are not named.

Yet, Fisher, Haldane, and Kimura did not make the argument in Box 1, did not follow the 4 steps, and did not derive Eqn IV!

Wednesday, July 03, 2019

Reactionary fringe meets mutation-biased adaptation. 4. What makes this new?

This is the fifth in a series of guest posts by Arlin Stoltzfus on the role of mutation as a dispositional factor in evolution.



Reactionary fringe meets mutation-biased adaptation. 4. What makes this new?
by Arlin Stoltzfus

Scientists value novelty because it signifies untapped potential: a new idea has not been interrogated, applied, and extended. The more novel an idea, the greater its potential to re-shape our discourse and advance our understanding beyond the well tried ideas of the past.

Tuesday, July 02, 2019

Reactionary fringe meets mutation-biased adaptation. 3. The causes and consequences of biases in the introduction process

This is the fourth in a series of guest posts by Arlin Stoltzfus on the role of mutation as a dispositional factor in evolution.


Reactionary fringe meets mutation-biased adaptation. 3. The causes and consequences of biases in the introduction process
by Arlin Stoltzfus

As discussed previously, mutation-biased adaptation occurs in the laboratory and in nature. In the cases that have been examined, modest several-fold mutational biases have modest several-fold effects on the changes involved in adaptation.

Reactionary fringe meets mutation-biased adaptation

Introduction
1. The empirical case
2. Some objections addressed
3. The causes and consequences of biases in the introduction process
4. What makes this new?
How can this happen? Classical thinking says that mutation is a weak pressure easily overcome by selection. This "opposing pressures" argument was invoked by Fisher (1930), Haldane (1933) and Wright (1931), as well as Huxley, Ford, Stebbins, Simpson and others. On this basis, it is assumed that the effects of mutation bias will be seen only in neutral evolution, where the opposing pressure of selection is absent, or with unusually high mutation rates.