Altenberg-16

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Altenberg-16 is an international group of evolution theorists.

The group met in July 2008 at the invitation of Gerd B. Müller at the Konrad Lorenz Institute for Evolution and Cognition Research (KLI) in Altenberg in Lower Austria for a symposium as part of the Altenberg Workshops in theoretical biology . The aim of the symposium was to create a common basis for how the Darwinian-Mendelian synthetic theory of evolution could be converted into an expanded synthesis in the theory of evolution .

The results of the conference were published in April 2010 in the work Evolution - The Extended Synthesis, edited by Gerd B. Müller and Massimo Pigliucci .

After the conference, some of the 16 participants sat for the establishment of the concept of evolution Advanced Synthesis ( Extended Evolutionary Synthesis , EES) one, but thus met with massive part criticism from colleagues, who regarded the new term for simply unnecessary.

Topics of the synthetic theory of evolution identified as open

One part of the group argued that the so-called synthetic theory of evolution , the classical theory on the evolution of organisms, ignored a number of factors. The significance of many of these factors has only been recognized or empirically investigated in the course of the last two decades:

ontogenesis

Embryonic development is treated as a ' black box ' in the synthetic theory of evolution . The production of phenotypic variation in development is taken for granted. The synthetic theory of evolution relies on the occurrence of random mutations in inheritance and the frequencies of genetic variants in populations. Scientists who drew attention to the importance of development early on, such as Conrad Hal Waddington , were not considered by the synthetic theory of evolution. The new evolutionary developmental biology that emerged in the early 1980s will become an important part of extended synthesis.

Inheritance

In comparison to the primarily Mendelian genetic inheritance theory of the synthetic theory of evolution, inheritance is now seen in an expanded framework. Epigenetic forms of inheritance have also been added. It should be DNA methylation only one of several new views.

ecology

The synthetic theory of evolution is essentially based on the assumption of the Weismann barrier , according to which it is not possible that germ cells and thus the DNA can be hereditary changed for the next generation by environmental influences. This restriction, also known as neo-Darwinian dogma , is now generally considered to be outdated. Modern evolutionary research now knows a large number of empirical studies according to which environmental conditions influence evolution (e.g. work on Darwin's finches , the taming of silver foxes by Belyayev, etc.). See also the experiments by Conrad Hal Waddington .

The theory of the niche construction of the British John Odling-Smee represents an essential pillar of the extended synthesis. It shows how populations of organisms create their own environment (e.g. termite structures ) and how these environmental properties in turn influence the evolution of those living things. This applies e.g. B. also for the spread of algae and the associated oxygen production in the atmosphere up to humans who create culture in whose environment their own evolution takes place.

Genotype-phenotype relationship

The synthetic theory of evolution still assumes that there is a 1: 1 relationship between genes and phenotypic characteristics. This view was later loosened. The synthetic theory of evolution, however, remains limited to a deterministic relationship between genotype and phenotype. The more recent research shows that both due to environmental influences during development ( plasticity ) and due to the emergent properties in the development of complex systems, one can no longer speak of a deterministic relationship. As West-Eberhard put it: “One can never say that the individual genome controls development. Development depends in every step on the pre-existing structure of the phenotype, a structure that is complexly determined by a long history of influences from both the genome and the environment. "

Internalistic factors of evolution

The synthetic theory of evolution explains evolution primarily through the action of natural selection and thus emphasizes the role of external factors acting on organismic populations from outside. The extended synthesis adds the importance of developmental components to this approach and emphasizes the effect of internal organizational principles.

Not gradual variation

For the synthetic theory of evolution, evolutionary change takes place exclusively in gradual, smallest steps, which over the course of many generations could accumulate to phenotypically larger variations. Such a view gives the natural selection 'the direction' over what emerges adaptively. The evolutionary biology and the expanded synthesis accepted discontinuous forms of variation and phenotypic innovation in evolution, caused among other things by thresholding effects in development . In the classical view, such discontinuous variations would be caused by genetic mutation and natural selection, but could, according to West-Eberhard and others, arise from direct environmental effects on embryonic development. The continuity of the changed environmental conditions would maintain the new variation in the population until the new features were fixed in the further course of evolution through genetic assimilation . The extended synthesis adopts this concept of facilitated variation .

Agenda items of the Altenberg-16-Symposium

The symposium dealt with the following questions:

  • How should one weight the factor embryonic development?
  • Is Evolution Always Gradual?
  • Is selection the only organizing principle?
  • On which levels does natural selection work?
  • Are there discontinuities in macroevolution?
  • Don't DNA-based forms of inheritance exist?
  • How do evolutionary innovations come about?
  • What role do exogenous influences play?
  • What role do genomic factors play?
  • Is there a paradigm shift in evolutionary theory?

The participants

Attendees university Compartment u. selected focal points
John Beatty (USA) Vancouver History and Philosophy of Biology
Werner Callebaut (Belgium) Limburgs Philosopher, philosophy of science
Sergey Gavrilets Tennessee Mathematics, ecology, population genetics, Adapt. Landscapes
Eva Jablonka (Israel) Tel Aviv Genetic u. epigenetic inheritance, behavioral and cultural evolution
David Jablonski (USA) Chicago Geophysics, biogeography,

Speed ​​u. Species v. Macro Evolution, Non-Accidental Innovations

Marc Kirschner (USA) Harvard Systems Biology, EvoDevo , Facilitated Variation
Alan Love (USA) Minnesota Philosophy, philosophy of science, developmental biology
Gerd B. Müller (Austria) Vienna Theoretical biology , EvoDevo , innovation (evolution) , evolution of development processes
Stuart A. Newman (USA) new York Cell biology , developmental biology , anatomy , physical evolutionary biology, evolution of metazoa , theory of DPMs
John Odling-Smee (Great Britain) Oxford Behavioral biology, niche construction , inheritance
Massimo Pigliucci (USA) Stony Brook Biology and Philosophy. Philosophy of biology, speed and Species v. Macroevolution ; Innovations, phenotypic plasticity
Michael Purugganan (Philippines) new York Biology, genetics, genomic networks
Eörs Szathmáry (Hungary) Budapest Genetic u. epigenetic inheritance , language evolution, system transitions, evolution theory
Günter Wagner (USA) Yale Evolutionary formation of morphological features, evolvability
David Sloan Wilson (USA) Binghampton Multilevel selection theory
Gregory Wray (USA) Duke Developmental biology, embryonic gene expression, genomic networks

criticism

In a joint statement in the journal Nature (2014), seven biologists expressed criticism of the term initiative that some conference participants had subsequently pursued. The seven critics were:

  • Gregory A. Wray (Department of Biology at Duke University in Durham, North Carolina, USA)
  • Hopi E. Hoekstra (Department of Biology at Harvard University in Cambridge, Massachusetts, USA)
  • Douglas J. Futuyma (Department of Ecology and Evolution at Stony Brook University in Stony Brook, New York, USA)
  • Richard E. Lenski (Department of Microbiology and Molecular Genetics at Michigan State University in East Lansing, USA)
  • Trudy FC Mackay (Department of Genetics at North Carolina State University in Raleigh, USA)
  • Dolph Schluter (Department of Zoology at the University of British Columbia in Vancouver, Canada)
  • Joan E. Strassmann (Department of Biology at Washington University in St Louis, Missouri, USA)

They summarized the initiative's concerns as follows and criticized it as superfluous:

“More precisely, they [the initiative's representatives] advocate that four phenomena are significant evolutionary processes: phenotypic plasticity, niche construction, including heredity, and developmental bias. We fully agree with this and we deal with it ourselves.

However, in our opinion, these processes do not have to be brought into focus to such an extent that the introduction of a new term such as "extended synthesis in the theory of evolution" is justified. "

The critics commented on the four subject areas mentioned by the initiative as follows:

Phenotypic plasticity

The role of phenotypic plasticity in evolutionary change is so well documented that it does not need to be emphasized again. “The question of whether plasticity can control genetic variation as part of the adaptation process is less clear. Over 50 years ago, developmental biologist Conrad Waddington described a process he called genetic assimilation. New mutations can convert one plastic property into another, which subsequently develops without the specific cause. There are only a few examples of this outside of the laboratory. Whether this is due to the fact that this phenomenon has not yet been seriously considered or whether it is a real rarity in nature, we can only find out through further investigations. "

Niche construction

The new name does not change the fact that evolutionary biologists have been researching feedback mechanisms between organisms and their environment for more than a century. "Such amazing adaptations as termite mounds, beaver dams and the courtship behavior of the bowerbirds have long been the focus of evolution studies."

Including inheritance

So far there is no solid evidence that inherited, epigenetic modifications (part of so-called inclusive inheritance ) play a major role in adaptation. “Not a single new feature is known that is based solely on epigenetic mechanisms and not also on its gene sequence. Both aspects should be examined more closely. "

Developmental Bias

Due to a lack of data, it is currently not possible to assess the role of 'one-sided development' ( developmental bias ) in evolution. “Ultimately, however, it is not a question of the extent of the feature variation or the exact trigger mechanism. The only decisive factor is the inheritable differences in the characteristics, especially those with a selective advantage. "

Conclusion

In summary, the critics came to the following assessment of the term initiative:

“We can discuss a lot about whether all these phenomena have not already been considered enough. Or we can roll up our sleeves and get to work and discover its real meaning by establishing the theoretical foundations and building a solid collection of empirical studies. Eternal discussions do not help the idea either. "

literature

  • Suzan Mazur: The Altenberg 16 An Exposé of the Evolution Industry. Berkeley 2009, ISBN 978-1-55643-924-7 .
  • Massimo Pigliucci, Gerd B. Müller (Ed.): Evolution - The Extended Synthesis. MIT Press, 2010, ISBN 978-0-262-51367-8 .

Web links

Individual evidence

  1. ↑ Massimo Pigliucci, Gerd B. Müller (Ed.): Evolution - The Extended Synthesis. MIT Press, 2010.
  2. ↑ a b K. Laland, T. Uller, M. Feldman, K. Sterelny, GB Müller, A. Moczek, E. Jablonka, J. Odling-Smee, GA Wray, HE Hoekstra, DJ Futuyma, RE Lenski, TF Mackay , D. Schluter, JE Strassmann: Does evolutionary theory need a rethink? In: Nature. Volume 514, Number 7521, October 2014, ISSN  1476-4687 , pp. 161-164, doi: 10.1038 / 514161a . PMID 25297418 . German translation
  3. ^ A b Eva Jablonka, Marion J. Lamb: Evolution in four dimensions. Genetic, Epigenetic, Behavioral and Symbolic Variation in the History of Life. MIT Press, 2005.
  4. ^ John Odling-Smee: Niche Inheritance. In: Massimo Pigliucci, Gerd B. Müller (Ed.): Evolution - The Extended Synthesis. MIT Press, 2010, p. 175 ff.
  5. ^ J. Richerson, R. Boyd: Not by Genes alone. How culture transformed human evolution. University of Chicago Press
  6. ^ Mary Jane West-Eberhard: Development Plasticity and Evolution. Oxford University Press, 2003, p. 29.