Science Literature

In 2005, Massimo Pigliucci, in a book review for Nature, wrote: "The clamour to revise neo-darwinism is becoming so loud that hopefully most practising evolutionary biologists will begin to pay attention. It has been said that science often makes progress not because people change their minds, but because the old ones die off and the new generation is more open to novel ideas." This clamour has not diminished in succeeding years, and one recent evidence of this was a private meeting in Altenberg, Austria, on 10-13 July 2008. This event was publicised in March by Susan Mazur, and her recent comments on the meeting are linked here.

What lies beyond the Modern Synthesis?

However, this blog is to draw attention to a piece in Science from Elizabeth Pennisi. According to Pigliucci, the attention created by Mazur's write-up "frankly caused me embarrassment". The reasons for this are not altogether clear, because there is no doubt that the Altenberg meeting was designed to address the problems of a failing theory. Scientific advances have revealed blind spots in the neo-darwinian synthesis and it is time for a change.

More than genes pass on information from one generation to the next, for example, and development seems to help shape evolution's course. "Many things need fixing," emphasizes one invited speaker, Eva Jablonka of Tel Aviv University in Israel. "I think that a new evolutionary synthesis is long overdue."

Major advances have been made in developmental biology, but these advances reinforce the idea that "development constrains evolution". Neo-darwinians do not warm to this idea, because they have promoted the concept of the adaptive landscape, where there is innate plasticity and where all barriers to transformation can, in principle, be overcome. Discussions of the limits to variation are alien to their mindset. However, once it is recognised that stasis is as important to consider as variation, and that stasis can be a developmental phenomenon (not just governed by the environment), then there are important scientific issues to consider about the limits of variation. Until now, neo-darwinists have treated such questions as an intrusion of religious ideology into science. The contrasting perspectives are explained by Pennisi thus:

From the modern synthesis perspective, Wagner explains, "the body plan is a historical residue of evolutionary time, the afterglow of the evolutionary process" such that more closely related organisms share more features. The alternative view, he says, is that "body plans have internal inertia," and evolution works around this stability.

Another key area of interest concerns "regulation": this is a new buzzword in biology circles; "yet it's another concept virtually ignored in the modern synthesis". This is important because the mechanisms of neodarwinism have been recognised by the Altenberg group as rather ineffective. This follows from any empirical work on what these mechanisms actually achieve.

Bottom line: "New traits contain very little that is new in the way of functional components, whereas regulatory change is crucial," Kirschner and John Gerhart of the University of California, Berkeley, wrote in a supplement to the 15 May 2007 issue of the Proceedings of the National Academy of Sciences. (For my blog on this paper, go here).

A further gap in neodarwinian thinking is epigenetics. Environmental factors can influence the way genes are turned on and off and this creates a "bewildering increase in the complexity of the entire inheritance system". Although it is not mentioned by Pennissi, epigenetics is of interest to ID scientists because the complexity issues have stimulated design inferences.

Certain environmental conditions, such as diet during gestation, can alter the epigenetic patterns of the resulting offspring, and new traits that result can last for generations, says Jablonka, who has been striving to get recognition for this mode of inheritance for years. [. . .] "It's beginning to be accepted that [epigenetics] may actually have something to contribute to evolution," says Jablonka. She argues that because these chemical modifications change how tightly wound DNA is, they also influence other properties of a genome that are relevant to evolution. The coiling of a DNA strand, she points out, can alter the rate of mutation, the ease by which mobile elements can move around, the duplication of genes, and even how much gene exchange occurs between matching chromosomes.

With all this excitement, it is difficult to avoid being seen as a dull spoil-sport if you are a sceptic. However, Jerry Coyne obliges:

It's a joke, says Jerry Coyne of the University of Chicago in Illinois. "I don't think there's anything that needs fixing."

These discussions are interesting to ID scientists, not just because they are addressing issues that are of direct concern to the development of ID thinking. We do not have to presume common descent, and we may yet find that variation is within limits. We may find that the regulatory aspects of genetics are strong evidences for design. We may find that that epigenetics points to new levels of exquisite complexity that reveal the hallmarks of design. We do not presume the outcomes, so for us it is a genuine exploration. By contrast, the secularised approach to science must trace everything back to a universal common ancestor and must explain design in nature entirely by reference to natural causes.

Modernizing the Modern Synthesis
Elizabeth Pennisi
Science 321, 11 July 2008: 196-197 | DOI: 10.1126/science.321.5886.196

Seventy years ago, evolutionary biologists hammered out the modern synthesis to bring Darwin's ideas in line with current insights into how organisms change through time. Some say it's time for Modern Synthesis 2.0

See also:

Pigliucci1, M. Expanding evolution, Nature 435, 565-566 (2 June 2005)

Mazur, S. Altenberg! The Woodstock of Evolution? (Scoop! 4 March 2008)