Otto Heinrich Schindewolf was a proponent of "orthogenetic evolution". Most early concepts of biological evolution were based on essentialism and mostly assumed a plan, a purpose of evolution "`implemented'' by the Creator. Such goal directed evolution concepts are sometimes designated orthogenetic evolution.
In theories proposing "orthogenetic evolution" (literally, straight line evolution), macroevolution is thought to be of a different calibre and process than microevolution. Nobody has been able to make a good case for orthogenesis since the 1950s, especially since the uncovering of molecular genetics between 1952 and the late 1960s.
According to Gould and others (Mayr, 1982), however, no directionality can be found in evolution, if studied in detail:
"Our impression that life evolves toward greater complexity is probably only a bias inspired by parochial focus on ourselves, and consequent overattention to complexifying creatures, while we ignore just as many lineages adapting equally well by becoming simpler in form. The morphologically degenerate parasite, safe within its host, has just as much prospect for evolutionary success as its gorgeously elaborate relative coping with the slings and arrows of outrageous fortune in a tough external world. "
[SJ Gould (1994) The evolution of life on the earth. Scientific American 271:4, 85-91}
Today orthogenetic theories are no longer accepted by most biologists because a clear overall tendency or direction cannot be detected in the development of or universe or the evolution of the various species.
[I got these info from Talk origins]
Edited on, March 30, 2005, 4:06 AM GMT, by Arnab.
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