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Our understanding of man’s place in the universe Eörs Szathmáry Collegium Budapest Eötvös University “In between infinity and nothing” • “For after all what is man in nature? A nothing in relation to infinity, all in relation to nothing, a central point between nothing and all and infinitely far from understanding either. The ends of things and their beginnings are impregnably concealed from him in an impenetrable secret. He is equally incapable of seeing the nothingness out of which he was drawn and the infinite in which he is engulfed. “ Blaise Pascal (1623-1662) Units of evolution 1. multiplication 2. heredity 3. variation hereditary traits affecting survival and/or reproduction The major transitions (1995) * * * * * These transitions are regarded to be ‘difficult’ Difficulty of a transition • Selection limited (special environment) • Pre-emption: first come selective overkill • Variation-limited: improbable series of rare variations (genetic code, eukaryotic nucleocytoplasm, etc.) Difficult transitions are ‘unique’ • Operational definition: all organisms sharing the trait go back to a common ancestor after the transition • These unique transitions are usually irreversible (no cell without a genetic code, no bacterium derived from a eukaryote can be found today) Recurrent themes in transitions • Independently reproducing units come together and form higher-level units • Division of labour/combination of function • Origin of novel inheritance systems Increase in complexity • Contingent irreversibility • Central control Chemical evolution was a race between tar formation and life formation Chemical networks Life Tar What fraction of planets would end up with just tar? Gánti’s chemoton model (1974) metabolism template copying membrane growth ALL THREE SUBSYSTEMS ARE AUTOCATALYTIC Pathways of supersystem evolution metabolism MB boundary MT template BT MBT INFRABIOLOGICAL SYSTEMS Primate phylogeny Chronology and geography The coevolutionary star and the human adaptive suite The social brain On human cooperation • Bowles, S. (2006) Group competition, reproductive levelling, and the evolution of human altruism. Science • A possible explanation—that groups with more altruists survive when groups compete—has long been judged untenable on empirical grounds for most species. On human cooperation II. • Empirical estimates show that genetic differences between early human groups are likely to have been great enough so that lethal intergroup competition could account for the evolution of altruism. • Crucial to this process were distinctive human practices such as sharing food beyond the immediate family, monogamy, and other forms of reproductive levelling. On human cooperation III. • These culturally transmitted practices presuppose advanced cognitive and linguistic capacities, possibly accounting for the distinctive forms of altruism found in our species. 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 Design features of language • Compositionality (meaning dependent on how parts are combined) • Recursion (phrases within phrases) • Symbolicism (versus icons and indices) • Cultural transmission (rather than genetic) • SYMBOLIC REFERENCE and SYNTAX Three interwoven processes • Note the different time-scales involved • Cultural transmission: language transmits itself as well as other things, and has its own dynamics Understanding language evolution is difficult BUT: 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? Patterns are made up of naturally occurring vocal patterns • Learning to classify by operant conditioning • This is NOT production! Note on human understanding unknown time known Boundary to the unknown known known time Infinite, limited progress knowledge Speciesspecific limit time