Editing Modern synthesis (20th century) (section)

===Towards a replacement synthesis===
[[File:Modern Synthesis Limits.svg|thumb|upright=2.2|Inputs to the modern synthesis, with other topics (inverted colours) such as developmental biology that were not joined with evolutionary biology until the turn of the 21st century<ref name="Kutschera Niklas 2004"/>]]

Biologists, alongside scholars of the history and philosophy of biology, have continued to debate the need for, and possible nature of, a replacement synthesis. For example, in 2017 Philippe Huneman and Denis M. Walsh stated in their book ''Challenging the Modern Synthesis'' that numerous theorists had pointed out that the disciplines of embryological developmental theory, morphology, and ecology had been omitted. They noted that all such arguments amounted to a continuing desire to replace the modern synthesis with one that united "all biological fields of research related to evolution, adaptation, and diversity in a single theoretical framework."<ref>{{cite book |last1=Huneman |first1=Philippe |last2=Walsh |first2=Denis M. |title=Challenging the Modern Synthesis: Adaptation, Development, and Inheritance |url=https://books.google.com/books?id=72EwDwAAQBAJ&pg=PT76 |year=2017 |publisher=[[Oxford University Press]] |isbn=978-0-19-068145-6 |pages=76 (Chapter 2)}}</ref> They observed further that there are two groups of challenges to the way the modern synthesis viewed inheritance. The first is that other modes such as [[epigenetic inheritance]], [[phenotypic plasticity]], the [[Baldwin effect]], and the [[maternal effect]] allow new characteristics to arise and be passed on and for the genes to catch up with the new adaptations later. The second is that all such mechanisms are part, not of an inheritance system, but a [[Developmental systems theory|developmental system]]: the fundamental unit is not a discrete selfishly competing gene, but a collaborating system that works at all levels from genes and cells to organisms and cultures to guide evolution.<ref>{{cite book |last1=Huneman |first1=Philippe |last2=Walsh |first2=Denis M. |title=Challenging the Modern Synthesis: Adaptation, Development, and Inheritance  |year=2017 |publisher=[[Oxford University Press]] |isbn=978-0-19-068145-6 |pages=Introduction}}</ref> The molecular biologist [[Sean B. Carroll]] has commented that had Huxley had access to [[evolutionary developmental biology]], "embryology would have been a cornerstone of his Modern Synthesis, and so evo-devo is today a key element of a more complete, expanded evolutionary synthesis."<ref name=Carroll_2008>{{cite journal |last1=Carroll |first1=Sean B. |author1-link=Sean B. Carroll |title=Evo-Devo and an Expanding Evolutionary Synthesis: A Genetic Theory of Morphological Evolution |journal=Cell |date=2008 |volume=134 |issue=1 |pages=25–36|doi=10.1016/j.cell.2008.06.030 |pmid=18614008|s2cid=2513041 |doi-access=free }}</ref>
<!--
    Please don't add more and more stuff that isn't 20th century here, this is not an ongoing history of all future biology but a (completed) article about something that finished in the 20th century --- thanks!
-->