The Shifting Gene Frequencies paradigm, which has shaped evo thinking for generations, says
* evo is SGF
* evo happens in pops
* causes of evo are forces that shift freqs
* to study causes is to study #popgen
* all of evo (macroevo) follows from SGF
To understand ongoing debates about alternative causes and research programs, the SGFP is like the hidden part of the iceberg
It is one of the ways that the historic Synthesis reaches out to us from beyond the grave
1/?
The screencast begins by explaining how the SGFP provides clear powerful guidance on how to think about, and how to study, evo
Next, it covers forces and modeling. In the SGFP, evo is formalized as movement of a pop in a frequency-space
but the forces theory only works when evo stays in the *interior* of a freq-space, i.e., when evo takes place by shifting alleles already present
without origination events that jump the system from the surface into the interior where sel and drift operate
2/
So the SGFP leads to results like Dobzhansky's extrapolationism and the Haldane-Fisher "opposing pressures" arg that fail when origination events matter
In the latter part, I focus on some of these issues, and I discuss ongoing and recent complaints about orthodoxy that can be seen as criticisms of SGFP, in regard to reductionism, determinism, plasticity, etc.
https://molevol.org/opposing-pressures-argument/
3/
My arg about how the SGFP does not rely on genetic determinism is possibly rubbish, and the arg about niche construction doesn't go far enough. I'll do better next time
This SGFP screencast is from an unfinished series, after the SGF *theory* and before I try to pay off the "beyond the SGFP" theme with an alt theory of forces and alt paradigm focused on dual causation
It all comes out (eventually) on this channel
4/4
Arlin Stoltzfus