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Towards and Extended Evolutionary Synthesis. Eörs Szathmáry. München. Collegium Budapest Eötvös University. What I am omitting. VERY mathematical aspects, such as Adaptive dynamics Statistical mechanics as applied to multilocus and quantitative genetics
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Towards and Extended Evolutionary Synthesis Eörs Szathmáry München Collegium Budapest Eötvös University
What I am omitting • VERY mathematical aspects, such as • Adaptive dynamics • Statistical mechanics as applied to multilocus and quantitative genetics • Evo-Devo (too much for this talk) • Most of epigenetic inheritance • Astrobiology (so far only hunches)
J. Huxley (1942) Evolution: the Modern Synthesis • Can hardly be modern • Is it wrong? • No, BUT • It is INCOMPLETE
Units of evolution • multiplication • heredity • variability Some hereditary traits affect survival and/or fertility
Chemical evolution was a race between tar formation and life formation Chemical networks Tar Life What fraction of planets would end up with just tar?
The major transitions (1995) * * * * * These transitions are regarded to be ‘difficult’
Molecular hypercycle (Eigen, 1971) autocatalysis heterocatalytic aid
Parasites in the hypercycle (JMS) short circuit parasite
The stochastic corrector model for compartmentation Szathmáry, E. & Demeter L. (1987) Group selection of early replicators and the origin of life. J. theor Biol.128, 463-486. Grey, D., Hutson, V. & Szathmáry, E. (1995) A re-examination of the stochastic corrector model. Proc. R. Soc. Lond. B 262, 29-35.
The structure of the genetic code • Amino acids in the same column of the genetic code are more related to each other physico-chemically
The RNA world may have preceded the RNA-protein world • Easy optimisation (with limits) • Many artifical ribozymes (BUT no replicase) • Coenzymes • Ribozyme doing peptidyl transfer during protein synthesis in ribosomes • Amino acyl-tRNA synthetases are NOT the most ancient proteins • 20 residues are better than 4 in catalysis
Why is language so interesting? • Because everybody knows that only we talk • …although other animals may understand a number of words • Language makes long-term cumulative cultural evolution possible • A novel type of inheritance system with showing “unlimited hereditary” potential
What is so special about human language? • Basically, it is the fact that we make sentences out of words, using grammar • Languages are translatable into one another with good efficiency • Some capacity for language acquisition seems to be innate
Recuerdos de mi vida (Cajal, 1917, pp. 345–350) “At that time, the generally accepted idea that the differences between the brain of [non-human] mammals (cat, dog, monkey, etc.) and that of man are only quantitative, seemed to me unlikely and even a little offensive to human dignity. . . but do not articulate language, the capability of abstraction, the ability to create concepts, and, finally, the art of inventing ingenious instruments. . . seem to indicate (even admitting fundamental structural correspondences with the animals) the existence of original resources, of something qualitatively new which justifies the psychological nobility of Homo sapiens?. . . ’’.
Challenges: a simple experiment (Hauser & Fitch) • Habituation experiments • Finite state grammar (AB)n is recognizable by tamarins • Phrase structure grammar AnBn is NOT. • Human students recognize both
Recursive syntactic pattern learning in birds? • European starlings (Sturnus vulgaris) accurately recognize recursive syntactic patterns • They are able to exlude agrammatical forms • Centre-embedding is not uniquely human?
An unpleasant problem Counting Real embedding
The coevolutionary wheel Intermediate capacities: e.g. analogical reasoning
A neglected process? • "A wonderful exploration of this strangely neglected topic, opening new vistas on how organisms - including humans - construct ecological niches over evolutionary time…. I think this book is a 'must read'." Robert May
Niche construction • Confounded vocabulary? • More than the extended phenotype? • Niche construction is the process in which an organism alters its own (or other species') environment, often but not always in a manner that increases its chances of survival.
Niche construction II • Not only does the environment cause changes in species through selection, but species also cause changes in their environment through niche construction • The effect of niche construction may be especially pronounced in situations where the alterations persist for several generations, introducing . Organisms inherit two legacies from their ancestors, genes and a modified environment.