theory of orthogenesis造句

In the 1950s the German paleontologist Otto Schindewolf developed a theory of orthogenesis, which claimed that variation tends to move in a predetermined direction.
His theory of orthogenesis ( straight-line evolution ) and eventual decay, claimed to be embedded within a cyclical view of the evolutionary process.
He was a proponent of the theory of orthogenesis, believing that several lineages of cribrimorph cheilostome bryozoans evolved progressively thicker and more elaborate skeletal structures which eventually became maladaptive, driving the lineage to extinction.
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