Convergence Theory (Evolution)
The convergence theory of evolution deals with the long-term geological forms of the origin of life. It says that life on earth had to arise as it is. The main proponent of the convergence theory is the British paleontologist and evolutionary biologist Simon Conway Morris . The convergence theory is based on the assumption that many functionalities developed independently in evolution. Examples are the wings of birds, bats or hymenoptera or the eye. Convergent evolution is even assumed within certain taxa , for example in the wing patterns of butterflies or the mouthparts of insects. The original chewing and chewing mouthparts have developed into different functional types, on the one hand the formation of proboscis in flower-visiting insects , which can very efficiently absorb nectar, and on the other hand the formation of different piercing-sucking mouthparts.
Wings had to be created because air existed, fins had to be created because water existed. Conway Morris speaks of functional constraints due to the physical conditions on earth . Life develops in a stable manner because nature provides the framework for it. The direction that life is taking is thus also predictable to a certain extent, since it inevitably follows the selective-adaptive rules. The convergence theory does not deny the influence of contingency events on the development of life, such as the meteorite impact on the Cretaceous-Tertiary boundary , but argues that such random events at best have a suspensive effect.
Concerning the origin of man, Conway Morris goes so far as to say that man was created with the Big Bang. Sooner or later, evolution inevitably had to arrive at an intelligent species. The development towards complexity and intelligence is program.
criticism
The convergence theory is in contradiction to the contingency theory . Since it argues in a strictly adaptionist way ( evolutionary adaptation ), it is negated by those evolutionary theorists who reject a consistently adaptionist argumentation in evolution, as it predominates in the USA ( synthetic evolution theory ). A staunch opponent of the theory was Stephen Jay Gould , who strongly opposed any immanent progress in evolution.
The convergence theory must also demonstrate the analogy , i.e. independence in the evolutionary development of features, or it must demonstrate that such macroevolutionary features are not based on close, common, homologous, but rather on analogous development paths. The better she succeeds empirically, the more convincingly she creates the basis for her adaptionist argumentation.
Web links
Individual evidence
- ^ Conway Morris, Simon: Beyond Chance. We humans in the lonely universe. Berlin University Press 2008.
- ^ Conway Morris, Simon: The Convergence of Life. In Fischer, Ernst Peter & Wiegandt, Klaus: Evolution. History and future of life. Fischer TB 2003
- ↑ Conway Morris, Simon: Aliens like you and me. In DIE ZEIT, August 19, 2004
- ^ Gould, Stephen J .: Illusion Progress. The many ways of evolution. Fischer TB 3rd edition 2004
- ^ Powell, Russel: Reading the book of life: Contingency and Convergence in Macroevolution. (Diss. Duke University) 2008