Summary
Thesis: Jablonka and Lambs thesis is that evolution is taking place in four distinct areas: genetic, epigenetic, behavioral and symbolic. They refute the standard dogma, that evolution is only possible on stochastic changes of the gene. The picture is a lot more complex as not only the phenotypes of nature have evolved but also the mechanisms that produce them.
The way the modern synthesis came into place needs to be looked as under a historical perspective. The idea of evolution was certainly in the air during the late 19th century. Unfortunately, no one including Darwin had a clear idea about how the mechanisms work. Instrumental in paving the way for the modern dogma was Weissman, who categorically denied an influence of the phenotype to the genotype. At the turn of the century Mendel hit the scene and it was clear that there must be something like a double stranded gene. During 1952 Crick and Watson discovered the double helix structure of the DNA. Furthermore it was discovered that radiation can change DNA. Hence it was assumed that all change leading to changes in the DNA and phenotype are stochastic events that are then selected by nature.
However, it was long understood that epigenetic mechanisms are at work in the forming of embryos. During embryo formation all cells have got the same DNA. Yet proteins formed are completely different during the formation of the embryo - otherwise it would be impossible to have a structured organism forming. The basic questions that was not asked - if these mechanisms are at work for the formation of embryos in any vertebrate and other multi cell organisms - why should they not be used by nature to change an organism over several generations and adapt to volatile environment?
These epigenetic changes are now well documented in many processes - while the new trend is still very young. Cancer might be related to epigenetic changes and could promise a new route into curing it. Viruses contain proteins that change 100.000 times faster than the rest of the organisms to provide an ever changing surface for attacking antibodies. Human's size is statistically dependent on different nutrition during pregnancy of mothers. Undernourishment can create smaller size babies who do not flourish well in rich environments. A high incidence of diabetes B is linked to it.
However, even on the behavioral front changes can happen. This is certainly so in the animal world, but even documented in the human world. Humans consume milk for a few thousand years only. In countries with higher milk consumption the population has adapted to be able to digest lactose sugars. This has happened particularly in northern Europe, less so in Southern Europe or Asia and Africa.
They then also discuss symbolic evolution. They are severely criticizing Dawkins concept of a meme. An egoistic concept that is jumping from human to human seems a bit imposable and one sided. Rather it seems that concepts themselves undergo an evolution. They are less static than a gene and more flexible, yet they are clearly able to influence the environment via the human brain.