Some evolutionary theorists - like Gerd Muller - think the Modern Synthesis is inadequate whens it comes to explaining macroevolutions:
"As can be noted from the listed principles, current evolutionary theory is predominantly oriented towards a genetic explanation of variation, and, except for some minor semantic modifications, this has not changed over the past seven or eight decades.
Whatever lip service is paid to taking into account other factors than those traditionally accepted, we find that the theory, as presented in extant writings, concentrates on a limited set of evolutionary explananda, excluding the majority of those mentioned among the explanatory goals above.
The theory performs well with regard to the issues it concentrates on, providing testable and abundantly confirmed predictions on the dynamics of genetic variation in evolving populations, on the gradual variation and adaptation of phenotypic traits, and on certain genetic features of speciation. If the explanation would stop here, no controversy would exist.
But it has become habitual in evolutionary biology to take population genetics as the privileged type of explanation of all evolutionary phenomena, thereby negating the fact that, on the one hand, not all of its predictions can be confirmed under all circumstances, and, on the other hand, a wealth of evolutionary phenomena remains excluded.
For instance, the theory largely avoids the question of how the complex organizations of organismal structure, physiology, development or behavior â whose variation it describes â actually arise in evolution, and it also provides no adequate means for including factors that are not part of the population genetic framework, such as developmental, systems theoretical ecological or cultural influences âŚ
A rising number of publications argue for a major revision or even a replacement of the standard theory of evolution, indicating that this cannot be dismissed as a minority view but rather is a widespread feeling among scientists and philosophers alike âŚ
Usually, a cursory acknowledgement of the problem of the origin of phenotypic characters quickly becomes a discussion of population genetic arguments about speciation, often linked to the maligned punctuated equilibria concept, in order to finally dismiss any necessity for theory change. The problem of phenotypic complexity thus becomes elegantly bypassed.
Inevitably, the conclusion is reached that microevolutionary mechanisms are consistent with macroevolutionary phenomena, even though this has very little to do with the structure and predictions of the EES.
The real issue is that genetic evolution alone has been found insufficient for an adequate causal explanation of all forms of phenotypic complexity, not only of something vaguely termed âmacroevolutionâ. Hence, the microâmacro distinction only serves to obscure the important issues that emerge from the current challenges to the standard theory.
(âWhy an extended evolutionary synthesis is necessary")
Also see âŚ
https://doi.org/10.1038/514161a
