Celebrating Darwin – looking for the ‘third wave’ in evolution

For the Darwin bicentennial, Seed magazine has an excellent collection of special articles.

One of the most seminal, to my mind, is Eva Jablonka’s call to integrate much more epigenetics into the modern neo-Darwinian synthesis.

Things like Lynn Margulis’ symbiosis have already been incorporated, as a big enough issue. But, as Jablonka notes herself, epigenetics would more directly challenge the integration of genetics into Darwinism that brought about the neo-Darwinian synthesis as the “second wave” of modern evolution.

After starting by noting the evidence is accumulating for more than just DNA being involved with evolution, Jablonka gives us a definition:

Epigenetics is a term that includes all the processes underlying developmental flexibility and stability, and epigenetic inheritance is part of this. Epigenetic inheritance is the transmission of developmental variations that have nothing to do with changes in DNA base sequences. In its broad sense, it covers the transmission of any differences that do not depend on gene differences, so it encompasses the cultural inheritance of different religious beliefs in humans and song dialects in birds. It even includes the developmental legacies that a young mammal may receive from its mother through her placenta or milk — transmitted antibodies, for example, or chemical traces that tell the youngsters what the mother has been eating and, therefore, what they should eat. But epigenetic inheritance is commonly associated with cellular heredity, in which differences that arise among genetically identical cells are transmitted to daughter cells.

She then notes that epigentics is connected to cell differentiation within an embryo, and even more, once differentiation starts, how kidney cells “reproduce true.”

Next, she notes that more and more evidence has accumulated for the transference of epigenetic traits between organisms.

From there, she goes to the mother lode of the need to go to a “third wave” of evolution:

Induced and heritable epigenetic change may guide genetic changes.

That’s one big reason I score down, and scorn, modern Pop Evolutionary Psychology, too. It takes no account of epigenetics.

Anyway, read the full story for an idea of where evolutionary research is headed, and where its main theorists need to be focused.