The Evolution of Incompatibilities – Molecular Mechanisms of Speciation

Speciation - the process by which new biological species arise - is one of the most important aspects of evolution and one of the central questions of evolutionary theory. In the course of this process, in which a species splits into two different biological species, reproductive isolation barriers develop between the previously interbreeding populations. The two species can no longer reproduce with each other. Their hybrids are sterile or infertile. Even in his seminal masterpiece "On the Origin of Species", Darwin could not find a satisfactory solution to the obvious paradox of why natural selection tolerates the development of these highly disadvantageous traits, such as sterility and infertility. Darwin’s contemporary, the philosopher John Herschel, therefore termed this problem the "mystery of mysteries". This "mystery of mysteries" is one of the most important unanswered questions in biological research over the last 150 years: How can two species evolve from a single species?

A new field of biochemistry and cell biology offers hope of solving this puzzle. It is estimated that the inside of each cell contains around five billion protein molecules. However, these molecules do not just float around, but rather come together in fascinating ways to form bubbles called condensates that pop up here and there and fuse together. These are collections of proteins and other large molecules such as nucleic acids. They do not form randomly, with their growth and decay instead being actively controlled by the cells. These protein condensates probably play an important role in many biochemical processes that take place in the cell, such as cell division, reading the genetic code or the production of proteins. These condensates enable the cell to maintain a certain order and organize the processes spatially and temporally. These molecular structures are probably also responsible for the emergence of incompatibility between species and for the sterility or infertility of hybrids. The question of whether these molecular mechanisms are responsible for the incompatibilities between two species will be investigated by the CAS Research Focus Group.


Prof. Dr. Axel Imhof

LMU Munich

Chromatin Proteomics

Working Group

  • Prof. Dr. Wolfgang Enard (Anthropology and Human Genomics, LMU)
  • Prof. Dr. Richard Merrill (Evolutionary Biology, LMU)
  • Prof. Dr. Jochen Wolf (Evolutionary Biology, LMU)
  • Prof. Dr. John Parsch (Evolution and Functional genomics, LMU)
  • Prof. Nitin Phadnis, Ph.D. (School of Biological Sciences, University of Utah)

Advisory Board

  • Christelle Fraïsse, Ph.D. (Sciences et Technologies, Université de Lille)
  • Janet Kelso, Ph.D. (Department of Evolutionary Genetics, MPI for Evolutionary Anthropology)

Visiting Fellow

Prof. Nitin Phadnis, Ph.D.

University of Utah

Genomics and Cell Biology